World News in Digestive Endoscopy
Issue 9, September 1998
Four years of intense and passionating work, first as Secretary General and, in the last 18 months, also as President due to the sad loss of Professor Rodolfo Cheli, teached me a lot. One major lesson is that still it is possible to find persons, colleagues, full of enthusiasm and keen to invest in non profit activities part of their overloaded professional time: I have to thank very warmly these colleagues, because without their help and advice it would have been difficult to fulfill the many tasks accomplished during these four years.
A second point I wish to stress is the growing self-consciousness in several countries of the key role of endoscopy in medical practice and the emerging need to keep together those practicing "the tube" because of common problems in defining their identity and in adding dignity to their work. The Societies and/or Groups devoted to endoscopy did increase during these years and it becomes more and more important to help them with a regular dissemination of news. In this respect the OMED Newsletter and Website seem to be the winning option.
A lot more of work remains ahead of us. I am confident that the new OMED management and the planned enlargement of the scopes and functions of the Committees will be able to respond positively to these tasks. To the new President and Board my best and sincere wishes for a fruitful activity.
Massimo Crespi, MD
and Secretary General 1994-1998
It is an honor and a great challenge for me to become President of the World Society for Digestive Endoscopy (OMED). No doubt, it is an honor to represent, Digestive Endoscopy and the endoscopists at a worldwide level. However, it represents also a great deal of hard work to face the numerous challenges that will appear during my term as President.
In the past, when rigid endoscopes were used, there were only few endoscopy societies around the world. With the advent of fiber-optic instruments, gastrointestinal endoscopy became a very attractive specialty, because of its increasing role in clinical diagnosis and management. Consequently a considerable number of endoscopy societies were founded. It was agreed that these societies should be put together according to their geographic location. Therefore three zones were credited, respectively the Asian-Pacific zone, the European zone and the Inter-American zone. Next step should be to congregate them towards a central coordination. It took until the 70s for the foundation of OMIED as the organization with the responsibility to oversee endoscopy, throughout the world. During this early stage, OMED was an amadoristic society, with no financial support and, therefore, with very few plans. Of course, it became necessary to have World Congresses of the specially. It was decided to have them in association with the already established World Congresses of Gastroenterology (WCOG). In this embryonic status, OMED was a "token" representative to the planning committee of the World Congresses. It was in the WCOG hold in Sao Paulo in 1986, then in Sydney in 1990 and finally, in Los Angeles in 1994 that it was given to OMED representatives the real possibilities to play a role in the organization of such congresses. A small portion of the registration fees and some extra-money from OMGE were given to OMED, though not sufficient to fulfill its aims.
Presently, OMED is experiencing a deep transformation. Thanks to the efforts of Massimo Crespi, Alberto Montori and Rodolfo Cheli has now established plans, such as educational programs for developing countries, videotape courses to be linked to either national congresses, meetings of endoscopy societies, hospitals or medical societies, and research projects.
For the next 4 years (1998-2002), during my term as President, my efforts will be focused in some priorities, such as:
1. To maintain OMED representing Digestive Endoscopy at a worldwide level by encourages and stimulating close cooperation and interchange between the Organization and its 3 Zones.
2. To maintain OMED as an independent organization. Since the introduction and the development of therapeutic, as well as the constant advances in technology, endoscopy has gained a unique position amongst Clinical Gastroenterology, Surgery (general and colorectal), Pathology and Radiology. Therefore, endoscopy must interact and be, regarded as, integral of clinical problems solving. Nowadays, it is not possible to treat Endoscopy as a secondary or adjunct to any specialty.
3. To encourage the adoption of OMED endoscopy training program as suggested at the Seminars on Education held at the Wordll Corngresses in Sao Paulo, Sydney and Los Angeles. Supervision of such programs will be responsibility of the education committees of each zone, according to their possibilities, under the coordination of OMED Education Committee. This would not interfere with the continuation of the educational program project for developing countries and with the videotape courses, already in course under Dr. Crespi.
4. To develop research activities, coordinated by OMED Research Committee.
5. To maintain and to stimulate standardization of Endoscopic Terminology under supervision of OMED Terminology Committee..
6. To maintain transmission of information by maintenance of the OMED Newsletter, the internet address and the web page.
7. To foster a close cooperation, with OMGE, scientifically, socially and economically.
OMED should have a permanent seat on the OMGE board with full voting privileges. On the other hand, OMGE should also have a permanent seat on the OMED board.
It is necessary OMED to be recognized as a full partner in the organization of the World Congresses of Gastroenterology and Endoscopy by OMGE.
It should be OMEDs responsibility to ensure a proper balance of endoscopic topics at those Congresses.
In addition, OMED should receive proper financial support from the profits of the WCOG in order to carry out its activities in administration, education, research, terminology and the other activities mentioned above.
This would include a need for committee meetings to be held at least twice a year (usualy during DDW and UEGW).
In summary, there is a great deal of work to be done. We need the support of endoscopists throughout the world to ensure that OMED is a reality.
Glaciomar Machado, MD
OMED, President 1998-2002
Glaciomar Machado Incoming President of OMED.
Introducer: Melvin Schapiro (President SIED)
Glaciomar Machado becomes the President of OMED during the VIII World Congress of Digestive Endoscopy in Vienna
It is with great pleasure and honor that I introduce you to our new President of OMED, Professor Glaciomar Machado. All of us who know and love him have come to simple call him Glaciomar as he is truly the representative of all of us.
Dr. Machado graduated in Medicine from the "Faculdade Nacional de Medicina da Universidade do Brasil" in 1966, and now, as Professor of Gastroenterology, has ascended to the position of Chief of the Gastroenterology section of that University in Rio de Janeiro.
Glaciomars background reflects a broad international training in Endoscopy and Gastroenterology. He served a fellowship under Dr. John Fordtran in the USA, studied Early Gastric Cancer Detection in Japan with the support of the Japanese government, completed a Ph.D. degree at the University of Bristol in England, and participated in academic programs throughout the world.
Glaciomar is one of the pioneers of modern diagnostic and therapeutic endoscopy. He was among the first to recognize the potential of, and utilize fiber optic endoscopes. He introduced ERCP to Latin America in 1973, EPT in 1975, and initiated the therapeutic endoscopic techniques of electrosurgical treatment of esophageal rings, and of choledocoduodenostomy.
Among his many contributions to the scientific literature, Glaciomar is the author of the only text book on Therapeutic Endoscopy in the Portuguese language. He is fluent in English, French, and Spanish and has participated as faculty of major Congresses throughout the world. He has been part of the scientific programs for the World Congresses in Mexico City, Madrid, Stockholm, Sao Paulo, Sydney and has delivered the "Schindler Lecture" at the WCOG in Los Angeles.
Glaciomars appointments and responsibilities have given him the extensive background necessary to serve our Society well as its next President. He is a member of the Brazilian Academy of Medicine where he holds the chair no. 18, has served as President of the Rio de Janeiro Digestive Endoscopy Society, President of the Brazilian Society for Digestive Endoscopy, President of the Inter American Society for Digestive Endoscopy and Secretary-General for the WCOG in Sao Paulo in 1986. In OMED Glaciomar has served as Secretary-General, vice President of the American Zone, and Chairman of the Education Committee.
I have been privileged to know Glaciomar as a kind, considerate, thoughtful and conscientious leader. Our Society will grow and prosper under his direction.
OMED Post-Graduate Course, Rome June 1-2, 1998
The Post-Graduate Course was organized within the 6th World Congress of Endoscopic Surgery under the auspices of the OMED, the EAES and the SAGES. The coordinators were J.R. Armengol Mirò, M.D. and M. Crespi, M.D. for OMED, Sir A. Cuschieri, M.D. and J.J. Jakimowicz, M.D. for EAES and J. Ponsky, M.D. and G. Van Stiegman, M.D. for SAGES
This interesting and successful Course was followed by 322 participants for 10 hours a day.
This Post-graduate Course with live interactive demonstrations (16 patients operated in 2 days) with Satellite connection with the Auditoruim of Alitalia where the Nurses Seminar took place and with the Hospitals in Milan and Taranto.
The Post-graduate Course was dedicated to "Diagnostic and Interventional Flexible Endoscopy; Interventional Radiology and Endoscopic Surgery: Competing, Complementary, Combined?". The contribution and participation of about 40 specialists in the different minimally invasive methods has brought up the possibility of managing patients through a cooperative efforts. When involved in the management of patients, only the knowledge of the possibilities and limits of each diagnostic and therapeutic approach makes it possible to achieve the best outcome with the lowest morbidity and costs. The Post-graduate Course has been focused mainly on all management options of digestive diseases of surgical interest, including interventional radiology and flexible endoscopy, with updating of all new-coming technologies, from the ultimate imaging technologies to the future role of telerobotics and virtual reality. The technological evolution has been indicated as the path for future wider and wider application of the principles of minimally invasive surgery.
Nonetheless, technology has not been the only commitment of the Course, where special regard has been given to the study and treatment of pre-cancerous lesions, early cancers and other malignancies. Therefore, at the end of the Course, the new profile for the Surgeons of the 3rd millennium has been drawn: an expert in sophisticated technology; good hand skills but also deep cultural roots.
Alberto Montori, M.D.
President, 6th World Congress
of Endoscopic Surgery
Photodinamic Therapy for Esophageal Disease
Photodynamic therapy (PDT) involves the systemic use of a photosensitizing drug which is activated by a light of proper wavelength and power to produce cell death. Cancers have preferential concentration of the photosensitizers allowing the physician to somewhat selectively treat malignant tissue and to degree spare normal tissues. The primary use for PDT in gastroenterology has been in esophageal cancer but trials are now underway to evaluate treatment effect in Barretts esophagus with dysplasia and in other GI cancers including biliary and colonic.
Porfimer sodium (Photofrin®, QLT Photo Therapeuctis, Vancouver, B.C.) is the pothosensitizer most used in clinical trials. It is now approved for use in certain types of esophageal cancer in the United States, Canada, the Netherlands, Japan and France. Photofrin® is also undergoing clinical trials in head and neck cancer, brain tumors and Barretts esophagus. Second generation drugs currently being tested in esophageal disease include 5-aminolevulinic acid and mTHPC.
With Photofrin®-PDT, the drug is injected IV followed by endoscopy in 40-50 hours. A cylindrical 2.5 cm diffuser attached to a fiberoptic probe carries dyelaser red light (630 nm) to the targeted esophageal disease. The light is delivered over a specified time (usually 12.5 min). One or more esophageal segments can be tereated during each session. Improvements in diffusers and other methods to deliver the light to the tissue should dramatically reduce the treatment time. Light delivery with Photofrin® can be repeated in 48-72 hrs if needed to achieve additional tumor destruction. Patients are usually treated in the outpatient setting.
Tumor destruction with PDT is significant. As expected, chest pain and nausea commonly occur following treatment but resolve in several days. Fever to 100-101° can occur. Sympathetic pleural effusion are also common following therapy. Perforation is unlikely but esophageal strictures occur in 10-40%.
Depending on clinical needs, more than 1 PDT session can be administered.
However, if PDT is going to be effective, 1 treatment typically improves cancer induced dysphagia. The duration of PDT response varies but is typically longer than the palliative effect of YAG laser. Photofrin® remains in body tissues for approximately 1 month necessitating the patient to protect themself from direct sunlight exposure during that period.
Sibille et al reported on 123 patients treated with PDT for esophageal cancer.
PDT was used as a singular therapy in 56 patients and as part of a multimodal protocol in 67. They found no difference in the response rate between PDT and multimodal therapy. A complete response at 6 months was obtained in 87% (99 of 114). Local recurrence occurred in 36 of these 99 patients 12 to 18 months later. For patients with uT1 and uT2 lesions 5 year survival was 33-36%. Many of these patients were non-operative candidates.
Photofrin®-PDT for Barretts esophagus and dysplasia or early esophageal cancer has been used most extensively by Oberholt et al. Using an esophageal centering balloon, they have treated over 200 patients. In their first 100 patients, high grade dysplasia (HGD) was eliminated in 88%, low grade (LGD) in 92% and Ut1 cancers in 77%. When combined with thermal ablation of small residual islands of Barretts persisting after PDT, complete elimination of Barretts was accomplished in 43 patients. Strictures occurred in 34% of patients but all responded to dilation. Subsquamous glandular mucosa was found in only 2 of the 100 patients but 2 others developed small nodules of HGD which were successfully retreated. One additional patient developed a small subsquamous adenocarcinoma which was also successfully retreated. Photofrin®-PDT is now being studied in an international, multi-center clinical trial in patients with Barretts esophagus and high grade dysplasia (HGD).
Gossner et al have used 5-aminolevulinc acid (5-ALA) induced protoporphyrin IX PDT to treat 32 patients with severe dysplasia or uT1 cancers with elimination of dysplasia in all and of 17 of 22 cancers. Malignancies greater than 2 mm deep required mTHPC PDT for deeper tissue effect. Barr et al have reported on 5 patients treated with 5-ALA-PDT. In both studies, persistence of subsquamous Barretts occurred and re-epitheliation with squamous mucosa was only partial following PDT.
In conclusion, PDT appears to hold considerable promise as an endoscopic therapy for palliating GI cancers and for curative therapy of dysplastic mucosa or superficial GI tract malignancies.
Bergein F. Overholt, MD
Knoxville, Tennessee USA
Lightdale CJ, Heier SK, Marcon NE, McCaughan JS, Gerdes H, Overholt BF, Sivak MV Jr, Stiegmann GV, Nava NR. Photodynamic therapy with porfimer sodium versus thermal ablation therapy with Nd:YAG laser for palliation of esophageal cancer: a multicenter randomized trial. Gastrointest Endosc 1995; 42: 507-512.
Overholt BF, Panjehpour M and Haydek J. Photodynamic therapy for Barretts esophagus: follow-up in 100 patients. Accepted for publication, Gastrointest Endosc, 1998.
Gossner L, Stolte M, Sroka R, Rick K, May A, Haln EG and Ell C. Photodynamic ablation of high-grade dysplasia and early cancer in Barretts esophagus by means of 5-aminolevulinic acid. Gastroenterology 1998; 114: 448-455.
Bar H, Shepherd NA, Robert DJH et al. Eradication of high grade dysplasia in columnar lined (Barretts) esophagus by photodynamic therapy with endogenously generated protoporphyrin IX. Lancet 1996; 348: 584-585.
Progress Towards a National Bowel Cancer Screening Program for Australia
Over the last 15-20 years, there have been a number of impressive achievements in cancer control in Australia. The most dramatic has been the substantial reduction in incidence and mortality of lung cancer in men as a result of media campaigns against tobacco use and legislation banning tobacco advertising. Incidence of lung cancer has now fallen below that of bowel, prostate and breast cancer. In addition, programs aimed at primary prevention or early detection are in place for control of cervical cancer, breast cancer, melanoma and non-melanotic skin cancer. However, until recently, bowel cancer has been neglected, despite the fact that it is the commonest cancer affecting both men and women in Australia and the second commonest cause of death from cancer after lung cancer .
The major reason for neglect was the lack of consensus among medical experts about appropriateness of screening for bowel cancer. Screening was "controversial". Without an agreed message, State Cancer Societies concentrated on symptomatic bowel cancer but gave the general topic of bowel cancer a low profile in their educational programs.
All that has changed. In 1991, the Australian Gastroenterology Institute (AGI), the educational arm of the Gastroenterological Society of Australia, produced guidelines on bowel cancer screening. The guidelines concentrated on recommendations for groups with above-average risk but drew attention to the four randomised controlled trials on faecal occult blood testing (FOBT) that were in progress (1-4). In August 1993, the Australian Cancer Society (ACS) held a consensus conference in Sydney, subsequently setting up a joint AGI/ACS working party to produce up-dated guidelines. The outcome was a second edition of guidelines on early detection, screening and surveillance released in November 1994 with endorsement from a number of medical organisations.
The 1994 guidelines were issued after publication of the results of the Minnesota trial (1) and referred to the imminent release of results of the Nottingham and Funen trials (2,3). Although advising against immediate establishment of a national screening program based on FOBT, the recommendations called for substantial funding for pilot programs to assess implications and mechanisms of introduction of such a program .
At the same time, exciting progress was occurring in cancer genetics, greatly stimulating interest in the coming place of genetic testing for inherited bowel cancer. Familial polyposis registers were established in all mainland States, starting with Western Australia in 1985, followed by programs for HNPCC and for people with an intermediate levels of risk for the disease.
In 1995, in response to the growing consensus among medical experts, the Federal Minister of Health instructed the Australian Health Technology Advisory Committee (AHTAC) to establish a working party to advise her on screening for bowel cancer. The working party first met in mid-1995 and was well placed to incorporate the results of the Nottingham and Funen trials that were published in December 1996 (2,3).
The official AHTAC report was released by the Minister in March 1998 (5), the major recommendations being as follows:
Average risk population (well population
aged over 50)
1) "On the basis of published evidence, and subject to favourable preliminary testing, it is recommended that Australia develop a program for the introduction of population screening for colorectal cancer (CRC) by faecal occult blood testing (FOBT) for the average risk population (well population aged over 50)."
2) "Given the uncertainties relating to the most effective means of implementing such a program and to the feasibility, acceptability and cost-effectiveness of such a program in the Australian setting, the program should commence with preliminary testing involving a number of pilot and feasibility studies."
Establishment of pilot and feasibility studies
These studies should address a number of questions, including:
3) Cost-effectiveness, compliance rates and safety of varying the upper age limit of the population offered screening.
4) Investigation of the performance characteristics of various FOBTs, with recommendations for selection of types of test to be used in screening.
5) Investigation of the desirable frequency of testing (annual or biennial).
6) Investigation of quality assurance aspects of sample collection and laboratory testing of FOBTs.
7) Investigation of the best method of achieving high quality and efficient follow-up of positive FOBTs.
8) Investigation of organisational issues to determine the optimal method of for delivery of a screening program.
9) Studies on participation and compliance, cost effectiveness, assessment of adverse physical and psychological effects of the program, development of programs for education of the public and the medical profession, and evaluation of the success and acceptability of the pilot programs.
The report states that, at this time, there is insufficient evidence either to accept or reject screening for bowel cancer using modalities other than FOBT. Further investigation of alternative approaches should be encouraged but some of the planned pilot studies could assess the improvement in detection rate of significant lesions when other screening modalities such as flexible sigmoidoscopy are added to FOBT.
High risk population
The report also recommends that individualised programs of surveillance should be developed for those at high risk for bowel cancer. Plans need to be developed for nationally coordinated approaches for management of familial adenomatous polyposis and HNPCC.
Detailed plans for the proposed pilot studies have been drawn up. The next requirement is financial support to allow them to proceed. Having accepted the recommendations of the report, the Federal Government is likely to announce availability of funding later this year. The pilot studies will take 3-5 years to complete. By that time, it should be possible to launch a nation-wide screening program for bowel cancer. Watch this space!
James St John , MD
Director Department of Gastroenterology
The Royal Melbourne Hospital
1. Mandel JS, Bond JH, Church TR, et al. Reducing mortality from colorectral cancer by screening for fecal occult blood. N Engl J Med 1993; 328: 1365-1371.
2. Hardcastle JD, Chamberlain JO, Robinson MHE et al. Randomised controlled trial of faecal-occult blood screening for colorectal cancer. Lancet 1996; 348: 1472-1477.
3. Kronborg O, Fenger C, Olsen J et al. Randomised study of screening for colorectal cancer with faecal occult blood test. Lancet 1996; 348: 1467-1471.
4. Kewenter J, Brevinge H, Engaras B et al. Results of screening, rescreening, and follow-up in a prospective randomized study for detection of colorectal cancer by fecal occult blood testing: results for 68,308 subjects. Scand J Gastroenterol 1994; 29: 468-473.
5. Colorectal Cancer Screening: a report of the Australian Health Technology Advisory Committee. Australian Commonwealth Department of Health and Family Services. Dec 1997.
Dieulafoy Disease. Endoscopic Diagnosis and Treatment
Upper gastrointestinal bleeding is one of the most frequent and serious emergencies in occidental countries, responsible, in our environment, of 3% of hospital admissions.
Among the non varicous gastrointestinal bleeding, one of the rarest etiologies, and, at the same time, one of the severest, is Dieulafoy Disease, which represents less than 1% of all causes of gastrointestinal bleeding. With relative frequency, a certain confusion is observed when commenting this entity and that of the ulcer with visible vas, due to a lack of rigour in anatomic, endoscopic and clinical criteria in a large number of publications.
Ulcer with visible vessel. (Fig. 1) It is the ulcer showing, within its crater, a more or less round structure, of variable colour, ranging between mother-of-pearl, reddish and blackish, supposedly corresponding to the vas which has bled, and which may bleed again. Generally, it is impossible to distinguish endoscopically between the remaining of a vas (visible vas) and a clot sealing the vascular tearing point.
Dieulafoy Disease (DD). (Fig. 2) It is a concept which should be kept for digestive bleeding secondary to the tearing of a vas of abnormal thickness for the mucosal territory it lies in, tearing being due to a superficial erosion of the mucosa, as can be verifyied in the histopathologica study of cases undergoing surgery (Fig. 3). As Dieulafoy used to say, it is an "exulceratio simplex" of the upper layer of the mucosa. The endoscopist will see a vas with no ulcer around it, or a slight, sometimes pulsating bulge on the wall, with a central point of hemostasia. If there is an ulcer, it is wrong to talk of DD. For this reason the term " Dieulafoy ulcer" is not correct. Most DD are seen in the stomach, but it may be observed anywhere in the digestive tube territory.
Until few years ago, only surgical treatment was feasible, but at the present time communications of successful treatment are increasingly frequent. Our first favourable results in endoscopic treatment of DD were obtained in 1986, and were presented at the VI European Congress of Digestive Endoscopy, celebrated in Rome in 1988.
To evaluate the efficacy of endoscopic treatment of Dieulafoy Disease, both in a short and in a long term.
Materials and methods
1. Selection of patients complying with the endoscopic criteria for hemorrhage due to Dieulafoy Disease, among all patients admitted because of upper gastrointestinal bleeding in our Hospital between November 1986 and May 1998.
2. Endoscopic treatment of patients with Dieulafoy Disease. During the first 3 years, patients were treated with injection of 1/10.000 adrenaline, 2% polidocanol and monopolar electrocoagulation. Since 1989, the treatment has consisted only in the use of adrenaline and polidocanol, administered in small injections in the bleeding point as well as around it.
4.873 patients with upper gastrointestinal bleeding were studied, 33 out of which met criteria for Dieulafoy Disease, representing a 0.67% of cases. Endoscopic treatment was carried out in 32 patients (30 of gastric and 2 of duodenal location).
In one case, diagnosis of jejunal Dieulafoy Disease was achieved during a preoperatory endoscopy, and he did not receive endoscopic treatment. The combined method of injection of drugs + electrocoagulation was used in 8, and injection of drugs (1/10.000 adrenaline + 2% polidocanol) was used in 24. Only 4 our of the 32 patients needed subsequent surgery for the control of new bleeding episodes. In the other 28 (87.5%), hemorrhage was definitely controlled.
Moreover, none of these 28 patients has presented new gastrointestinal bleeding episodes since hospital discharge. No complications were observed in this series.
1. There is a good response to endoscopic treatment of gastrointestinal bleeding due to Dieulafoy Disease.
2. A combination of chemical an thermic agents is as effective as the use of chemical agents alone. The relevant issue is destruction of the area of the bleeding vas.
3. Long term results are also very satisfactory.
J.L. Vazquez-Iglesias, MD
Division of Digestive Disease
Hospital Juan Canalejo
La Coruña, Spain
Currently, more than 90% of all common bile duct concrements can be removed via the endoscopic retrograde route by means of endoscopic papillotomy, stone extraction by basket and balloon catheters, or mechanical lithotripsy. Oversized, very hard or impacted stones, however, often still resist conventional endoscopic therapy. Laser lithotripsy represent a promising new endoscopic approach to the nonsurgical treatment of those common bile duct stones.
In 1986, common bile duct stones could be disintegrated for the first time in man via the endoscopic retrograde route by means of pulsed Nd: YAG LASER (1,2). In the meantime, experience of other groups have been reported mostly applying the pulsed dye laser (3).
However, to date, only about 120 patients have been treated worldwide with this new therapy concept, which is still an experimental clinical treatment. Certain problems concerning the laser lithotriptor devices, the endoscopic approach and energy application in the bile duct account for this fact.
For clinical application in gastroenterology, the only laser systems at present commercially available are pulsed dye and Nd: YAG lasers.
The pulsed Nd: YAG laser is a solid state laser emitting near infrared light (usually 1064 mm wavelength). Two different pulse qualities are used for laser lithotripsy: ms pulses (10-3 s) generated in the free-running operation mode and ns pulses (10-9 s) generated in the O-switched operation mode.
The free-running mode Nd: YAG laser produces light pulses up to some thousands of watts in a period of 2 ms.
The light transmission system consists of a simple highly flexible 200 m quartz fibre brought into direct contact with the stone. After guiding the fibre with laser pulses of lower energy (0,5 J/4 Hz) to the centre of the stone, the pulse energy is augmented (1.3 to 2.0 J/4 Hz). In this way, even giant calculi can be disintegrated into two to five fragments within seconds (5 to 90 s). The fragmentation of high vapour pressures at the fibre tip which make the stone breakup from its centre. Due to relatively high pulse energies, discrete thermal lesions of tissue in contact with the 2000 m fibre tip are possible. However, chronic experiments in dogs showed no complications in clinical and laboratory follow-up until four weeks after direct irradiation of the bile duct. Histological findings after that time were basically normal (4).
With the Q-switched operation mode, the pulsed Nd: YAG laser, nonlinear optical processes such as "plasma" induction and creation of a locale shock wave can be induced. By this method, a completely athermal transformation of light energy into mechanical energy is possible (5).
Due to the high power peaks of the "giant pulses" of the
Q-switched Nd: YAG laser, initially only relatively rigid fibre transmission systems could be used. The fibre core diameter was at least 600 m and an additional lens focusing system of "light pipes" at the distal fibre end were needed (6).
Hochberger has developed a highly flexible 300 m quartz light guide system which permits endoscopic retrograde application of the Q-switched Nd: YAG laser (7).
The laser plasma at the point of the mechanical shock wave is induced either in front or directly on the surface of the concrement.
Stone disintegration results in the removal of very thin sand grain or power-like fragments from the stone surface. There is no hazard of thermal damage to tissue applying this laser type.
In the flash lamp pulsed dye laser, organic dyes mostly dissolved in alcohol are used as active laser materia.
Best light absorption in gallstones and kidney stone is obtained in the blue-green light spectrum (8). For this reason, 504 nm wavelength is commonly applied, which can easily and effectively be generated using cumarin dye and which is less absorbed in hemoglobin than in bilirubin. The high absorption of biliary concrements for light of this wavelength facilitates the induction of a laser plasma with the relatively long microsecond (10-6s) light pulses of the dye laser. The fragmentation process itself is athermal, but induced by a thermal process (9,10).
After beating a small quantity of stone material at the rip of a 200 m fibre brought into direct contact with the stone surface, the plasma and consequently, the mechanical shock wave is induced.
The results of fragmentation is similar to that of the Q-switched Nd: YAG laser. The advantage of the dye laser lies in its simple fibre transmission system, corresponding to that of the free-running mode Nd: YAG laser an the use of low pulse energies (Ep 30 to 90 mJ; Pm 0.3 to 1.3 W). Contrary to the nanosecond pulse Q-switched Nd: YAG, the dye laser can induce thermal tissue damage.
At present, there are three different methods for endoscopic retrograde application of laser lithotripsy in the common bile duct (2).
If the stone can be cause in the lithotripter basket, it can be fragmented under x-ray control alone; the fibre is centered right in the middle of a laser basket by means of a central channel without any risk of accidental application of energy to surrounding tissue.
In the case of impacted stone, a similar idea is pursued using a balloon catheter with a central channel. The safest approach for stone fragmentation is the use of a "baby" or "mini" endoscope which is inserted into the bile duct via a "motherscope".
The reason which speaks in favour of laser lithotripsy compared to extracorporeal shock wave litrotripsy (11) is that laser lithotripsy can be executed in any endoscopy unit in the aim of endoscopic pretreatment, usually necessary for extracorporeal shock wave lithotripsy (contrast x-ray, papillotomy and insertion of a nasobiliary tube). Furthermore, laser lithotripsy is painless and therefore, does not require general anesthesia or additional medication besides the usual endoscopic retrograde cholangiopancreatography.
Complications in the clinical use of laser lithotripsy have not been reported so far as in electrohydraulic lithotripsy.
Jacob Rattan, MD
Gastroenterologic Department, Ichilov Hospital
Tel Aviv, Israele
1. Parisi A.F., Nieminen M., OBoyle J.E. Enhanced detection of the evaluation of tissue changes after acute myocardial infarction using colour encoded two dimensional echocaridography. Circulation 1982; 66: 764-770.
2. Lux G., Ell C., Hochberger J., Muller D., Demling L. The first successful endoscopic retrograde laser lithotripsy of common bile duct stones in man using a pulsed neodymium YAG-laser. Endoscopy 1986; 18: 144-145.
3. Kozarek R.A., Low D.E., Ball T.J. Laserlithotripsy of large bile duct stones. Gastrointest Endosc 1986; 28: 144-145.
4. Ell C., Hochberg J., Muller D., et al. Laserlithotripsy of gallstones by means of pulsed neodymium YAG-lager In vitro and animal experiments. Endoscopy 1986; 18: 92-94.
5. Boulnois J. : Photophysical process in recent medical laser developments: A review, Lasers Med Sci 1986; 1: 47-66.
6. Ell C., Wondrazek F., Hochberger J., Lux G., Demling L. Laser-induced shockwave lithotripsy of gallstones. Endoscopy 1986; 18: 144-145.
7. Hochberger J., Ell C., Gruber E., et al. Laserlithotripsy of biliary calculi by means of a Q-switched giant pulse Nd: YAG laser and highly flexible fiber systems. Gastroenterology 1986; 95: A213 (Abst.).
8. Nishioka N.S., Levins P., Murray S., Parrish J., Anderso R. Fragmentation of biliary calculi with tunable dye lasers. Gastroenterology 1987; 93: 250-255.
9. Tio T.L., Wijers O.B., Sars P.R.A., Tytgat G.N.J. Preoperative TNM classification of proximal extrahepatic bile duct carcinoma with endosonography. Semin Liver Dis 1990; 10: 114-120.
10. Dukes C.E., Bussey H.J.R. The spread of rectal cancer and its effect on prognosis. Br J Cancer 1958; 12: 309-320.
11. Sauerbruch T., Stern M. Fragmentation of bile duct stones by extracorporeal shock waves. Gastroenterology 1989; 96:146-152.
The experts in Terminology Meet in Rome, Italy, on May 1-2, 1998 under the Auspices of OMED, ASGE and ESGE
Minimal Standard Terminology
Version 2.0: Rome 1998
For over 20 years endoscopists in the United States and Europe have struggled to create a standard lexicon in digestive endoscopy. The efforts of hundreds of gastroenterologists from many countries and institutions culminated in the review and approval of the Minimal Standard Terminology version 2.0 in Rome, Italy. The importance of the MST 2.0 is not simply that for the first time the endoscopic community has agreed on a series of terms to define more precisely endoscopic observations. In fact, this activity has demonstrated the globalization of endoscopy and the impact of information system technology on the ability to integrate the interests of the international endoscopic community.
Terminology has been an issue in all corners of the globe. The OMED Committee on Terminology led by Professor Z Mar?atka began work on an endoscopic lexicon in 1978. The OMED Terminology is the most comprehensive list of endoscopic descriptive terms. The ASGE began its efforts in 1982 with the creation of the ad-hoc computer committee chaired by Dr. J Geenen and implemented by Dr. D Kruss. The result of this activity was the creation of the ASGE database which was the combination of a lexicon and software implementation that led to the creation of several large databases of endoscopic reports. These efforts did not gain widespread acceptance and in 1991, the ESGE undertook an effort under the leadership of Dr. M. Crespi to create the Minimum Standard Terminology. Participants form the ESGE, the United States and Japan met over the course of three years to produce the first version of the MST. The group set out several basic principles:
the lexicon should consist of the most commonly used terms in endoscopy,
the lexicon should follow a concept-modifier model,
redundant and synonymous terms should be eliminated
the lexicon should not specify software function but povide the lists needed for software development around a standard.
It was not sufficient to simply publish this lexicon but it was necessary to test the degree to which the MST could be used to describe endoscopic findings. Testing of the MST 1.0 was begun simultaneously in Europe and the United States. Approximately 20 centers in 12 countries produced over 25,000 endoscopic procedure reports. These results were reviewed in joint meetings between the ASGE, ESGE and Japanese Endoscopic Societies. Terms that occurred less that <0.1% were excluded and the section on ERCP was revised to reflect the complexity of this procedure. The ERCP revisions were designed to take into account the combination of maneuvers and observations that are made during the procedure. For example, a sphincterotomy may be done in order to cannulate the papilla and then visualize the duct. This is different from colonoscopy where maneuvers such as polypectomy are done based on the findings observed. The MST version 2.0 was completed after meetings in Rome of the Committee on Terminology and in New Orleans at Digestive Disease Week.
The Rome meeting on Minimum Standard Terminology version 2.0 was an important first step toward the development of an International Lexicon of Endoscopy. The unique collaboration between Gastrointestinal Endoscopic Societies has been recognized by the World Health Organization (WHO) as a model for international medical cooperation. The next steps for dissemination of this lexicon include:
support of the GASTER project designed to create a textual and visual dictionary to accompany the lexicon,
testing of the terminology in Japan, an effort led by Dr. Ogoshi and Dr. Fujino,
development of a conformance statement that enables purchasers of endoscopic software to determine the extent to which the MST is used,
introduction of the MST as a part of SNOMED International, the largest medical lexicon.
development of a Web-based mechanism to support revision and modification of the MST.
MST version 2.0 is edited by Dr. M. Delvaux and Dr. L. Korman. Each national endoscopic society will have the opportunity to translate the MST directly from the International Version. The national language version should be reviewed and approved by that society and then locally disseminated. Proposed changes and extensions to the MST will go through an editorial review process governed by the OMED Committee on Terminology and the Editors of the MST. This process will ensure that the MST is maintained and responsive to the needs of the International Endoscopic community. The further development MST will provide a standard for research and clinical care that will assure that our patients receive the highest quality of care.
Louis Y. Korman, MD
Chairman ASGE Computer Committee
Washington, DC, USA
The colonic mucosal surface, on close observation, is granular in appearance and demarcated into small areas called non specific grooves. When a blue dye such as indigo carmine or methylene blue is sprayed on the surface, the grooved pattern becomes clearly observable. In figure 1, the normal grooved pattern shows a regular arrangement.
Figure 2A shows a flat early cancer detected in the transverse colon by the finding of interruption in the vascular pattern. The extent and the surface structure of this lesion can not be clearly seen. By spraying the mucosa with a blue dye (indigo carmine), the extent and the minute surface structure of this lesion becomes clearly seen, which is not possible with conventional colonoscopy (Figure 2B).
Chromoendoscopy has been developed specifically in Japan since the 1970s and many Japanese endoscopists now routinely use this technique. However, despite data suggesting a clinical role for chromoendoscopy, this technique appears to be rarely applied in clinical practice in other countries. Herein I explain how we use this technique in Japan and its effectiveness in clinical practice.
Chromoendoscopy uses chemical compounds as stains or contrast agents to highlight subtle mucosal surface changes or abnormal gastrointestinal epithelium. Three basic types of chromoendoscopy are employed in gastrointestinal endoscopy at the present time and called the contrast, staining and reaction methods.
The contrast method highlights irregularities in the mucosal architecture by pooling of a blue dye solution in mucosal grooves and other interstices. This improves the precision of endoscopic diagnosis by defining minute and inconspicuous lesions that might otherwise be overlooked with conventional endoscopy. There are two methods of performing contrast chromoscopy, direct and indirect. In the direct method, the dye is applied under direct vision and is suitable for investigating lesions that have already been detected. With the indirect method, the dye is delivered either orally or anally and is effective specifically in the detection of lesions and lowers the possibility of their being overlooked.
The dye most frequently used for contrast chromoscopy is indigo carmine, the food additive known as Food blue No. 2. It has an acceptable daily intake of 2.5 mg/Kg body weight and is so poorly absorbed from the alimentary tract that it can safely be used for chromoendoscopy.
Indigo carmine does not actually stain the surface of the mucosa, as in the staining method, and can easily be washed away with water. Consequently, the dye can be applied any number of times with ease.
The staining method is based on the absorption of dye by epithelial cells, or permeation of the dye into necrotic tissue. It is a more specific method of chromoendoscopy, since the dye absorptive function of the mucosa or various lesions can be evaluated by endoscopy.
The staining method can be used to diagnose certain diseases, pathologic conditions, and mucosa states that are difficult to recognize with certainty using conventional endoscopic observation. Two examples are gastric intestinal and the state of the colonic mucosa in ulcerative colitis, to confirm whether the inflammatory process is active or healed. Methylene blue is the dye most frequently used for the staining method. In the reaction method, a dye applied to the mucosal surface reacts with a constituent of the epithelial cell or some mucosal secretion. There are two types, the Lugol method and the Congo red method.
Non-keratinized squamous epithelial cells contain abundant glycogen which reacts with Lugols solution. This reaction has been used to diagnose esophageal diseases such as esophagitis and carcinoma.
The Congo red method is based on the reaction that occurs between this dye and secreted hydrochloric acid. It is therefore used in defining the extent of the acid secretion in normal fundic mucosa. Using this method, the color of the normal fundic mucosa changes from red to dark blue, while the antral mucosal surface does not change color. As a result, this method is not suitable for morphologic observation.
Blue dyes, such as indigo carmine and methylene blue, are the most suitable for observation of gastrointestinal morphology and staining phenomena, because the blue color contrasts sharply with the reddish mucosa. Lugols solution and Congo red are also useful for certain purposes as explained above. Although almost no side effects from dyes used in chromoendoscopy have been reported, only the minimal amount of dye solution required for examination should be used. At the conclusion of the procedure any remaining pools of dye should be aspirated.
The following is a discussion of chromoendoscopy for each organ in an actual clinical setting.
Lugol staining is specifically used for the esophagus. After direct spraying with Lugols solution, normal esophageal mucosa is stained brown or dark brown and has a fine mucosal pattern suggesting a wrinkled texture. Esophageal cancer and esophagitis are not stained by Lugols solution. Therefore, this method is useful for detecting early cancer and defining the boundaries of invasive cancer.
The contrast method using indigo carmine is frequently used for the stomach and duodenum. The contrast method is very effective in detecting early gastric cancer and in recognizing the extent of cancer infiltration in the mucosa (Figure 3A, B).
This method is also useful to differentiate benign from malignant ulcers and may aid in determining whether or not an ulcer is recurrent. Early gastric cancer are not only difficult to detect endoscopically but also, when discovered, their true nature may not be recognized. With the contrast method however, it is not difficult to recognize such lesions and define their size, shape, number and distribution.
The villous pattern of the duodenum and individual villi are clearly defined by the contrast method. This method is helpful in determining whether a duodenal ulcer has healed completely and also in demonstrating a rare duodenal malignancy more clearly.
The contrast method and the staining method are specifically used for colonoscopy, but the contrast method is more popular than staining because of its ease of use and repeatability.
Colonic lesions originating form mucosa (except for submucosal tumor) are so certain to have a different surface pattern from the normal grooved one that it is not only easy to detect such lesions interrupting the grooves but it is also possible to investigate them more meticulously when using chromoendoscopy.
Figure 4 shows a flat elevated invasive cancer, 12 mm in size, detected in the ascending colon. The extent of this lesion can be recognized, but its surface structure can not be clearly seen. The contrast effect by indigo carmine spraying helps to visualize the non-specific grooves, and it is easy to recognize the extent of the lesion more clearly. In addition, the thin coating of the dye that remains on the surface clearly reveals the depressed part of the lesion that can not be seen through conventional colonoscopy. The existence of the depressed part and the magnified observation of the irregular surface pattern here cause us to highly suspect this lesions malignancy.
Dye spraying is an indispensable item for magnified observation.
After an endoscopic mucosal resection was performed for this lesion, magnified observation combined with an application of the dye was performed to check for any residual lesions at the resected margin. Using chromoendoscopy and magnified observation we can accomplish a more thorough endoscopic treatment.
Figure 5 is a diminutive flat adenoma. Methylene blue stains the normal mucosa around the lesion, but not the lesion itself. The staining differences between the lesion and normal mucosa are very useful for demonstrating the extent of the lesion. Methylene blue can be also used in the contrast method before tissue staining is completed in the several minutes during which this blue dye is scattered on the surface of gastrointestinal tract..
The technical difficulty of chromoendoscopy is minimal. There is a learning curve for endoscopic procedures, but proficiency in chromoendoscopy is usually attained with relatively few examinations. Cost and inconvenience is negligible. Most chromoendoscopy techniques add only several minutes to the length of an endoscopic procedure and most dyes are inexpensive (a few dollar for indigo carmine, methylene blue, or Lugols solution).
Chromoendoscopy improves the quality of gastrointestinal endoscopy, resulting in a degree of diagnosis and treatment that has heretofore not been possible with conventional endoscopy.
All patients undergoing endoscopy do not necessarily require chromoendoscopy.
The indications for chromoendoscopy are dependent upon each endoscopist who understands its clinical effectiveness. I propose that all endoscopists should learn chromoendoscopy as an optional endoscopic technique and be able to use it whenever necessary in actual clinical settings.
Hideki Mitooka, MD
Chief Center Digestive Diseases
and Internal Medicin
Kobe Kaisei Hospital
Fibrin Sealant: Endoscopic Indications and Results
Fibrin sealant is an agent widely used in many surgical disciplines for achieving hemostasis and tissue adhesion. During the last steps of normal physiological coagulation, hemostatic clots are formed which mainly consist of erythrocytes, thrombocytes and fibrinogen. The subsequent conversion of fibrinogen to fibrin monomers by thrombin in the presence of calcium ions and factor XIII leads to formation of a stable fibrin clot. Later, as wound healing progresses, fibrinolytic activity is induced by plasmin and breakdown of fibrin to fibrin degradation products takes place.
The hemostatic effects of fibrin sealant are an initiation of the last steps of physiologic blood coagulation. As soon as the two components fibrinogen and thrombin, for instance via a double lumen catheter come in contact with each other, fibrinogen is converted to fibrin by the action of the thrombin-component.
Fibrin sealant is used by gastroenterologists and surgeons for bleeding control, tissue adhesion, suture support, wound care and sealing of fistulae.
Fibrin sealant and Ulcer Bleeding
Persistent or recurrent bleeding occurs in about 20% of the patients presenting with a bleeding ulcer. In this group of patients, the mortality rate is still 11-14%. The morbidity and mortality rates are higher in patients with ulcers with endoscopic signs of recent hemorrhage.
These patients account for the majority of patients that require additional interventions. In Europe the most common technique used is subulcerous injection with epinephrine followed by sclerotherapy with 1% polidocanol. In around 10-20% of patients in whom hemostasis is achieved further bleeding will occur. In case of rebleeding repeated injection of a sclerosing agent will lead to more extensive ulceration with the risk of fatal rebleeding or perforation.
Injection of thrombin only or of fibrin sealant instead of epinephrine /polidocanol has been studied as single-injection therapy, and as repeated injection therapy. Thrombin and fibrin sealant causes only very limited tissue damage and can therefore be injected ad libitum and can be repeated. Also fibrin sealant forms a natural matrix for wound healing, whereas sclerosing agents cause thrombosis and further ulceration. Recently a randomized trial was published, comparing the safety and efficacy of repeated fibrin sealant injection and of single endoscopic injection of polidocanol in the prevention of rebleeding (1). A total of 854 patients with active gastroduodenal ulcer bleeding (spurting, oozing), or ulcers with a visible nonbleeding vessel, were randomized to one of the three endoscopic treatments: single application of 1% polidocanol, single application of fibrin sealant, or daily repeated application of fibrin sealant until the visible vessel had disappeared. All patients were pretreated with local injection of epinephrine (1:10.000) and underwent daily endoscopies until the signs of recent hemorrhage were not longer visible. Rebleeding rates among the patients in whom the rates could be assessed were 58 of 254 (22.8%) in the polidocanol group, 51 of 266 (19.2%) in the fibrin sealant-single group, and 41 of 270 (15.2%) in the fibrin sealant-repeated group. The difference between fibrin-repeated treatment and polidocanol 1% was significant (p=0.036). Treatment failures, making other treatments necessary (including surgery) were 34 of 261 (13.0%) in the polidocanol group, 34 of 274 (12.4%) in the fibrin sealant-single group, and 21 of 274 (7.7%) in the fibrin-repeated group. The difference between fibrin sealant-repeated treatment and polidocanol 1% was significant (p=0.046). The 30-day mortality rates and safety profiles of the three treatment strategies were similar. It was concluded that repeated injection of fibrin sealant is significantly more effective than injections with 1% polidocanol in the treatment of bleeding gastroduodenal ulcers. The lack of tissue damage and safety of fibrin sealant allows repeated injections until the ulcer base becomes clean or until the visible vessel is reduced to a flat brown spot. Probably the most important factor in hemostasis is complete obliteration of the feeding vessel. A single application sclerosing agent or a single treatment of thermal coagulation may not be effective enough, but the risk of extensive tissue necrosis and even perforation makes endoscopists reluctant to repeat these treatment modalities in case of rebleeding. Repeated injections of fibrin sealant however can be given without risk for further tissue damage, and are effective in vessel obliteration. A double lumen catheter is used for the injection of 1 ml fibrin sealant, which is flushed out of the catheter by 1 ml 0.9% saline.
Fibrin sealant and Fistulae
Because of the good biological properties including wound healing, fibrin sealant is used for closure of persistent bronchopleural fistulae, tracheo-esophageal fistulae, leaking duodenal stumps after surgery, peripheral bile leaks after liver resection etc. Groitl et al (2) reported on 84 patients with postoperatively leaking anastomoses treated with endoscopic application of fibrin sealant. After thorough cleaning of the fistula or abscess cavity, the fibrin sealant was applied. Usually several sessions were required, but finally 82% of proximal G I-and 61% of lower G I-tract leaks or fistulae were successfully closed. Eimiller (3) reported on 22 patients with Crohns disease and fistulae. In almost all patients rectovaginal, enterovesical, entero-entero and entero-cutaneous fistulae were successfully closed with only 17% recurrences.
Ambrose et al (4) treated 13 patients with persistent perineal sinus after proctectomy for inflammatory bowel disease or cancer. Previous attempts to close the sinus ranged from none to four revisions (mean 2.2). In four patients the sinus had subjectively improved and healed completely in 5 patients without recurrence in 129 patient months of follow-up. The authors suggest in view of the simplicity of the procedure and its low morbidity, it should be tried before embarking on major surgical procedures.
We were successful in closing postoperative leaks after esophago-cardial resection in 6 out of 8 patients, usually after one single application. Only small fistula with a diameter of less than 0.5 cm were considered candidates for this technique.
Engler et al (5) reported endoscopic occlusion with fibrin sealant of a persistent pancreatic fistula after acute pancreatitis. In three sessions over 6 days, 1-2 ml fibrin sealant injections were applied by ERCP into the fistula tract leading to complete occlusion without any further complication.
We recently treated a patient with a biliovenous fistula after percutaneous liver biopsy. Normally such a fistula closes spontaneously after a few days, but in this patient a dominant extrahepatic stricture due to primary sclerosing cholangitis prevented spontaneous closure. Due to the pressure gradient bile leaked into the venous system leading to extreme jaundice with a serum bilirubin of more than 2000 µmol/l (117 mg/dl). Superselective cannulation by ERCP of the leaking peripheral bile duct and subsequent injection of fibrin sealant closed the fistula immediately, with rapid decrease in serum bilirubin (6).
Data from the literature warrant further widespread application of fibrin sealant for several indications, like post-operative leaks, fistulae, and ulcer bleeding.
Erik A.J. Rauws, MD
and Kees Huibregtse, MD
Department of Gastroenterology and Hepatology
University of Amsterdam, NL
1. Rutgeerts P, Rauws EAJ, Wara P, Swain P, Hoos A, Solleder E, Halttunen J, Dobrilla G, Richter G, Prassler R. Randomised trial of single and repeated fibrin glue compared with injection of polidocanol in treatment of bleeding peptic ulcer. Lancet 1997; 350: 692-696.
2. Groitl H, Horbach T, Stangl R, Scheele J. Endoskopische Applikation von Fibrinkleber zur Behandlung von Anastomosen insuffizienzen, Perforationen und Fisteln im Gastrointestinaltrakt. In: Technik der Fibrinklebung in der Endoskopischen Chirurgie. Manegold BC, Lange V, Salm R (Eds). Springerverlag 1994; 85-91.
3. Eimiller A. Endoskopische Fibrinklebung zur Behandlung von Fistula bei Morbus Crohn. In: Technik der Fibrinklebung in der endoskopischen Chirurgie. Manegold BC, Lange V, Salm R (Eds). Springer-Verlag 1994; 103-105.
4. Ambrose NS, Alexander-Williams J. Appraisal of a tissue glue in the treatment of persistent perineal sinus. Br J Surg 1988; 75: 484-485.
5. Engler S, Dorlars D, Riemann JF. Endoskopische Fibrin verklebung einer Pankreas gangfistel nach akuter pankreatitis. Dtsch Med Wschrochenschr 1996; 121: 1396-1400.
6. Sattawatthamrong Y, Janssens AR, Alleman MJA, Huibregtse K, Rauws EAJ, Tytgat GNJ. Endoscopic treatment of bilhemia following percutaneous liver biopsy (submitted).
Survey on Endoscopic Practice in Africa
When we consider endoscopy in Africa, 3 points are of relevance:
An important delay in comparison with North America and Western Europe in implementing endoscopy, and in the introduction of the new instruments and accessories.
A great inequality between geographic areas and countries.
Existence of two areas, with differences in terms of approach to endoscopy: the anglophone area and the francophone one.
Who performs endoscopy?
In most of a cases, physicians, specialized in gastroenterology are allowed to practice endoscopy, but in Egypt and South Africa, surgeons, general practitioners and occasionally poediatricians perform the procedure.
Training and maintaining competence:
There is no special diploma for performing endoscopy. The medical school by the means of University hospitals offers 3-4 year-training programs in gastroenterology, including endoscopy. An applicant must complete the two years residency in internal medicine prior to the admission to to gastroenteroloy diploma.
Training is done through practical medical education, conducted by seniors in University hospitals, and endoscopy Units, by the means of a teaching attachment when fiberoptic endoscopes are used, or by video if available. No threshold number of G.I. endoscopy procedures is required to achieve initial competence Diagnostic procedures for upper and lower gastrointestinal tract are widely learned, while operative endoscopy and new techniques are usually reserved for senior endoscopists working in University hospitals . In Egypt, to practice endoscopy, one should have completed a certificated training course (usually 6-12 months) in a well known G.I. endoscopy Center. At the end of the course a final evaluations achieved through a special form and questionnaire. The trainee should be approved by Medical Societies and the Medical Egyptian Syndicate. Besides the practical aspect, the training includes, lectures, symposiums, annual conference, and workshops. The "credit hours system" is absent, except in South Africa where there is a CME program with points being allocated for attending lectures, workshops, tutorials, etc.
Compliance with the C.M.E. program by the year 2000 will affect all the registred gastroenterologists.
Diagnostic endoscopy is carried out in hospitals and private practice. Guidelines for G.I. unit are absent but in fact they exist in training hospitals with good standards.
Endoscopy units of reference
Are unusual and are located in the University Hospitals, well equipped, with different rooms for each procedure, good maintenance, sedation and disinfection. They are the elective areas for operative endoscopy. In south Africa, there is a managed two years career registrar program in all the teaching units. On completion they are required to perform an examination and submit evidence of attendance to courses and completion of activities.
Elsewhere, usual endoscopy for upper and lower G.I. tract in widely carried out even in private practice.
The nonimmersible endoscopes are absolete, and are not used any more. The fiberoptic endoscopes are the majority while videos, are rarely available.
Type of examination
If all the endoscopists are allowed to carry out upper and lower G.I. endoscopy, the operative endoscopy is reserved to the experienced endoscopists in the University Hospitals or specialized centers.
The instruments for echo endoscopy are very few, while endoscopic surgery is increasing dramatically.
The endoscopy examination
Indications and informed consent
Usual endoscopy is carried out, after a clinical examination, almost without explanations, or informed consent, except in South Africa and in the Egyptian University Hospitals. In fact, the patient asks for care, voluntarily, and his frequent low education level doesnt permit discussion. We have also to keep in mind that guidelines prepared for one community are not necessarily applicable to others, regarding the differences in approach due to the geography, race, social class, ethnic background, education, local referral patterns, and sophistication of local endoscopy services.
Upper G.I. endoscopy, the most frequent examination, is carried out without any sedation, or topical pharyngeal anesthesia, in outpatient basis. This attitude is well accepted by the patients, allowing saving of time which is not a negligible aspect of endoscopy in developing countries. Diagnostic colonoscopy is also frequently carried out with spasmolytics only and sedation is reserved to emotional people, or when theraphy is needed like polypectomy which is rarely needed, except in the schistomas infection areas. All the other operative techniques are always carried out with sedation and monitoring on an inpatient basis. A report is always written for each patient.
Due to the low number of endoscopes and the enormous number of endoscopies needed, time for disinfection is very short, so that it still remains the "Heel of Achilles"of endoscopy in Africa. For a long time, it consisted in wiping the endoscope with a sponge and soap, followed by water aspiration and air insufflation, despite the high prevalence of virus (HIV-HBV), bacterias, and parasites. Moreover up to a recent date the endoscopes were kept in their case at the end of the session without banging for night. The lack of guidelines contributes to this situation. But the latter has been changing quickly for approximately 5 years and standards of disinfection are increasing. Automated systems were bought recently for equipping some centers of reference. In our Unit in Tunis, in South Africa and some places in Egypt the disinfection is done with standards accepted abroad. We have to keep in mind, that manual cleaning of the material is the most important step of disinfection.
The reuse of the accessories is a crucial point. Of course, sclerotherapy needles are never reused, while sphincterotomies, biopsy forceps, and disposable material are reused considering their cost and restricted availability.
Objective evaluation of competence, and technical skills in G.I. Units is absent, related to the lack of license for performing endoscopy, the small number of endoscopists and endoscopy Units. It is very difficult, at the moment, to have supervisors for evaluating the endoscopists skills, the endoscopic units standards, and the examination quality.
Major problems and future
The reduced availability of endoscopes is related to their high cost.
Perhaps it will be possible to lower the price, by reducing, or better by abolishing the import customs duties (like in Tunisia) or by manufacturing fiberoptic endoscopes cheaper.
The maintenance difficulties
Disinfection: In the absence of guidelines and laws? It is our duty to address great efforts in this direction by establishing guidelines and adequate legislation.
The endoscopic assistants are not always aware of the nosocomial infection risk. So their training is mandatory not only for disinfection, but also for handling the material and helping the endoscopist during the manoeuvres. On the other hand, the complexity of the machineries and the scarceness of skilled technicians for repairing the systems are a real problem resulting in delay for patients, and in frustration for endoscopists.
Training and maintaining competence
The problems in developing endoscopy in Africa are daunting. If diagnostic endoscopy learning is easy, the new technologies an therapeutic endoscopy require complex cognitive and manual skills that can be acquired only after a long period of training. The modern endoscopes with video images are a good way of learning combined with a hand-eye coordination. How can we remedy to this situation? The solution could be found by:
The creation of endoscopy centers of excellence able to offer a short term visitor experience in potentially hazardous techniques, with the collaboration of international experts, under the responsibility of the OMED as on example. Workshops could be organized with live demonstrations, where the experts can bring their "savoir faire" to the African Endoscopists. We are used to hold such workshops in our Unit in Tunis, once a year since 1991.
Giving the opportunity to the African endoscopists to do training in reputed centers abroad with the help of the OMED.
Enhancing the learning of endoscopy by the creation of a certificate, for the future endoscopists, with a prerequired number of endoscopies for each technique. The program of the post graduate training has to be defined clearly.
Maintaining competence is mandatory, and could be done in the endoscopy centers of excellence.
These pessimistic data are not very encouraging. There is a gap between the great number of endoscopies needed, and the reduced number of endoscopes. Of course, we have to learn a lot from the experience of the American and the European Societies of endoscopy to ovoid their worse aspects in order to bring up endoscopy in Africa to the international level and guidelines. So we have to be updated, and in the same time to be adjusted to our amount resources. This situation is as impossible as to square a circle.
Truly we have many miles still to go before.
Habib Ben Khelifa, MD
Dr. Harold M. Bloch (Cap Town, South Africa)
Dr. Francis Klotz (Dakar, Senegal)
Dr. Foued Thakeb (Cairo-Egypt)
For their precious help.
40th Jubilee Congress of the Hungarian Society of Gastroenterology. Balatonaliga, June 1998
The Gastroenterology Section of the Hungarian Society of Internal Medicine has been founded in 1957 by young researches (internists and surgeons) interested mainly in digestive tract diseases. In this era, the political life in Hungary was not favourable to the development of an indipendent subdiscipline, the basic and clinical research works were not sufficiently supported, neither by the social atmosphere, nor by financial grounds. In spite of this fact, the devoted and tremendous work of Professor Magyar and Varrò conduced to the organization of the first national congress, in 1958, and the establishment of the indipendent Society of Gastroenterology, in 1966. For the past 40 years, the increasing number of enthusiastic gastroenterologists (at the present time more than 1400), international congresses (ASNEMGE 1976) and postgraduate courses (ESGE 1992, 95), several publications and multimedia teaching materials denoted the continuous progress of the Society.
The 40th - jubilee annual meeting was held at the Lake Balaton, June 9-13, 1998, with more than 1500 Hungarian doctors and several invited lecturers from abroad. After the meeting of GE nurses and endoscopy associates seven satellite symposia presented the current status of modern treatment in hepato-gastroenterology. New trends in ulcer-reflux disease (BYK GULDEN). Clarithromycin the cornerstone of Helicobacter eradication (Abbott), Omeprazole dosage form development (ASTRA), High enzyme-content treatment in maldigestion (Knoll), Forty years of enzyme substitution (Solvay), Hepatic encephalopathy pathogenesis, diagnosis and treatment (Merz), Challenges in GERD management and H.p. eradication ((Richter). At the end of the congress a successful interactive teaching course was held including 200 invited general practitioners on the diagnosis and treatment of functional dyspepsia (sponsored by Janssen-Cilag).
The main topic of the jubilee congress was: Infection in gastroenteroloy. During another scientific symposia and round table conferences several important gastroenterological themes were discussed, as: Diagnosis and treatment of cholestasis, Invasive and minimal invasive interventions in gastroenterology. Problems of enteral and parenteral nutrition. In this year the Hetenyi Memorial Lecture was presented by Zs. Tulassay. With the title: Osteopenia in gastrointestinal diseases.
The inauguration of Honorary Members is always a remarkable event of our congress.
This jubilee year we had the honour to welcome Massimo Crespi (Rome, Italy) who gave us an excellent overview on Helicobacter Pylori and gastric cancer. Dr. M.J.G. Farthing (London, UK) outlined the new concepts in host-pathogen interactions in the gut and discussed the therapeutic implications. Peter Funch-Jenses (Aarhus, Denmark) discussed the Scandinavian experience with laparoscopic fundoplication, and finally Anton Vavrecka (Bratislava, Slovakia) demonstrated his results on endoscopic treatment of chronic pancreatic disease.
As always since 1992, a multimedia Learning Center (sponsored by GLAXO-Medicom) was provided for the young clinicians and medical students, with a refreshed and completed teaching material. The nice weather and the usually friendly atmosphere made the meeting unforgettable for the guest and participants.
L. Simon, MD
Past President of HSG
Interamerican Society of Gastrointestinal Endoscopy (SIED), 1997 Research Committee Survey
During 1997, the Research Committee of the Interamerican Society of Gastrointestinal Endoscopy (SIED), conducted a survey directed to all the Societies of Gastrointestinal Endoscopy within the Latin-American area on "Endoscopic equipment, Accessories, Disinfection and Endoscopy training". As illustrated by the response rate, the survey was well received among constituent societies. A total of 58 endoscopy centers completed the survey: 19 from Brazil, 18 from Argentina, 9 from Colombia, 5 from Uruguay, 4 from Bolivia, 2 from the Dominican Republic and 1 from Peru.
Regarding the frequency of the various endoscopic studies, there was only minor variation between centers: the most frequent studies being esophagogastroduodenoscopy (comprising 65% to 70% of all studies), colonoscopy (20% to 23%) and duodenoscopy (10% to 15%).
Only four of the centers used videoendoscopes exclusively. Most (30) used both videoendoscopes and fiberscopes; a significant number (20), also utilized videocameras, i.e., an adaptor connection to transform a fiberoptic image into a video image. Only 3 centers did no possess video equipment. Fiberscopes are, therefore, still widely used in Latin American countries, even though videoendoscopes are increasing in popularity.
Of those centers that use fiberscopes, 80% use immersible equipment. Of importance in relation to disinfection, 13% of all centers continue to use non-immersible endoscopes and 7% use both immersible and non-immersible. Given the fact that non-immersible equipment has not been manufactured for several years, it can be concluded that a significant number of centers still use this outdated equipment. Of all videoendoscope systems, 60% were housed in endoscopy centers and 40% in public hospitals. This distribuction was similar in all countries with the exception of Argentina where 75% of videoendoscopes were in private and 25% in public centers. This difference in distribution may be explained by the fact that, in Argentina, videoendoscopy is frequently reimbursed at a higher rate than fiberoscopy. In 75% of responses from centers in all other countries, it was stated that both types of endoscopy were reimbursed at a similar rate. It should be noted that 28% of centers responding to the questionnaire did not answer this question; these conclusions are, therefore, drawn from an incomplete sample.
Costs of Endoscopy
Inquiries regarding fees charged for endoscopic studies provided widely variable responses: charges for diagnostic videoesophagogastro-duodenoscopy ranged from U.S.$ 150 to 600, in various countries. In those countries where there was a difference in fees between video and fiberoscopy (notably Argentina), fiberoscopy was reimbursed at half, or even less, of the rate for videoendoscopy. In general, the fee quoted included the use of the equipment and accessories, as well as, nursing support and other ancillary services. The fee for therapeutic endoscopy varied widely and it was very difficult to draw any conclusions.
Cleaning and Disinfection
All centers performed manual cleasing of endoscopes and accessories with a neutral detergent or an enzymatic soap and then disinfected with 2% glutataldehyde. Six centers used ethylene oxide for accessories and only 4 used automated "washing machines". Seventy-five percent disinfected equipment after each examination; 25% performed this, only at the end of the day or following cases with known infectious diseases.
With regard to who performs cleaning and disinfection, 41 centers stated that disinfection is performed by trained paramedical personnel; 28 stated that disinfection is carried out by the physician (in several centers both of those options were operative) and only 3 centers use operating room personnel who do not have specific training in endoscopic cleaning and disinfection.
With regard to protection of staff: 100% of responders use gloves, 53,5% protective goggles, 48,3% chin straps, 39,6% disposable aprons and 15,5% boots. Some centers took precautions only in those cases where they knew that the patient was HIV (+).
With regard to access to accessories, 40 centers responded that accessories can be easily obtained in their own countries; 15 experienced some difficulties and 3 did not answer this question. The reasons for such difficulties included the following: high price, absence of hospital budget, lack of stock in the country and a bureaucracy that hinders purchase of accessories. When asked about what accessories are used in the different centers, most (50) use well-known international brands; 12 (from Argentina and Brazil), use national brands (domestically manufactured) and 9 (in Argentina, Bolivia and Brazil) use self-manufactured accessories. Accessory prices vary widely. For example, the price of a papillotomy knife ranged from U.S. $200 to 700 and a polypectomy snare from U.S. $65 to 500. In Argentina and Brazil, domestic brands are, on average, half the price. In Latin America, accessories are, onaverage, twice or three times more expensive than in USA or Europe and this is a major problem for endoscopy centers. All centers stated that they re-use accessories that have previously been disinfected with 2% glutaraldehyde or ethylene oxide.
Endoscopy Training and Certification
With regard to gastrointestinal endoscopy training, all countries responded that their gastroenterology residencies include training in gastrointestinal endoscopy; both diagnostic and therapeutic. The location of such gastroenterology training is as follows: University Center 51, Private Institution 19, Public Hospital 18. Thirty-five centers responded that specialized, concentrated, endoscopic training experiences were available in their country; in addition to a standard gastroenterology residency. The duration of this additional endoscopy training is variable, but they generally last between one years and two. With regard to the administration of these specialized endoscopic training portions, 27 responses stated that these were administered by Universities, 12 by Scientific Societies, 10 by private and 5 by other hospitals. When asked about wherether a higher qualification in gastroenterology enables a physician to perform endoscopies, all countries answered affirmatively except for Brazil where 14 Centers answered positively an 5 negatively.
With regard to the granting of certification in gastroenterology and endoscopy, 25 answered that such certification is granted by Scientific Societies, 20 by Universities, 16 by Medical Colleges and 9 by a giverment Ministry. In some countries more that one mechanism was operative. In Peru, the Dominican Republic and Uruguay, certification does not require a practival demonstration of endoscopic skills. In other countries requirements appeared to vary. In Brazil 18 Centers stated that a practical demonstration is required; one stated that it is not. In Colombia, 4 answered positively and 5 negatively; in Argentina, 2 answered positively and 16 negatively and in Bolivia, 2 answered positively and 2 negatively.
The last question was whether centers were prepared to receive foreign doctors for endoscopy training. To this, 45 answered affirmatively, 6 negatively and 7 did not answer.
Nevertheless, in all countries that responded to the survey there is at least one center willing to receive foreign trainees.
Dr. Jorge L. Rainoldi, MD
Chairman Scientific Committee S.I.E.D.
Commentary by Eamonn M.M. Quigley
Chairman Research Committee OMED
Dr. Rainoldi and his colleagues are to be congratulated on this important survey. This report illustrates that meaningful surveys are feasible an worthwhile. Several important findings deserve emphasis. These include the persistence of non-immersible endoscopes in a minority of centers and significant variations in policies for cleaning, disinfection, and staff protection.
Reflecting high costs and difficulties with accessory cleaning, re-use of accessories following disinfection seems universal and should be contrasted with emerging policies regarding single-use in Europe an North America. While the basic components of gastroenterology training appear similar, the details of endoscopic training and certification, in particular, vary considerably both between and within various countries. Surveys such as this provide "real" data on endoscopic practive and should serve as the basis for future projects in endoscopic research, training and education.
OMED Post-Graduate Course, Moscow, April 23-24, 1998
Host: Russian Gastrointestinal Society
Held at the National Cancer Research Center
This first OMED live course on advanced endoscopy held in Moscow was a success by any criteria. The host faculty from Russia were extremely pleasant and receptive, and took care of the foreign guests in a spirit of true friendship and cooperation. The audience was attentive, interested, and participated actively in the question session. The National Cancer Research Center (Foto) is a large and busy complex which provided excellent opportunities for television transmission to the audience as well as facilities for x-ray and biliary tract work.
Here, (Foto) Professor Poddubny, President of the Endoscopic section of the Russian Gastroenterology Association, is meeting with Drs. Schapiro, Crespi, Montori and Kruse.
The Russian faculty members were always exchanging dialogue, thoughts, and discussion with the foreign faculty members.
The restaurant "Acropolis", on the grounds of the Cancer Center, permitted all of us to get together while Dr. Crespi gave a toast to all of our comrades.
The gestures of appreciation would not be complete without thanks to Svetlana Karpova, who was so energetic, cheerful, and acted as our official interpreter throughout the entire course.
Although there was not much time for sightseeing, we were able to see Red Square, both in daylight and at night. (Foto night)
In addition to live demonstrations, of EUS by Dr. Fockens, and of ERCP by Doctors Armengol Mirò and Kruse, there were also demonstrations of colonoscopy by Doctors Waye and Schapiro, and several discussion sessions with lectures interspersed throughout the two-day course.
We would like to thank Dr. Poddubny, and our hosts from Olympus, Mr. Kadoya, Mr. Sato and Mr. Tamai for their generous support of this remarkable international course and symposium.
The course was truly a memorable event for the faculty and for all the participants. I would like to personally extend my thanks and gratitude to OMED for having invited me to this remarkable scientific venture, to Dr. Poddubny, to Dr. Fedorov for their organizing abilities, and Dr. Kuzmin for his excellent handling of the video sequencing and for all the work and effort he put in "behind the scenes". Lastly, thanks to the Olympus Company for making this all possible. I look forward to seeing all of you on the international tour in the future.
Jerome D. Waye, MD
Chairman OMED Education Committee
New York, USA
Helicobacter Pylori and Digestive Endoscopy
The relationship between Helicobacter pylori infection and digestive endoscopy began immediately after its discovery by Warren and Marshall in 1982 in Australia. The evolution of our knowledge of this bacteria and the developments of endoscopy and related technics, justify the analysis and discussion of the relationship under the following topics:
Endoscopy as a diagnostic tool for Helicobacter pylori infection;
culture and antibiotic sensitivity testing
Endoscopy versus non invasive methods
Endoscopy as a therapeutic tool
Complications of endoscopy
transmission of Hp infection
The evolution of endoscopy
endoscopic 13C urea breath test -EUBT
Endoscopy as a diagnostic tool for Helicobacter pylori infection
As a diagnostic tool endoscopy allows different forms of study of Helicobacter pylori infection. The macroscopic appearance may show lesions such as gastroduodenal ulcers, erosions and/or antral nodularity that may be highly suggestive of H. pylori infection.
Endoscopic acquisition of gastric biopsies can lead to a definitive diagnosis of the Hp infection through indirect or direct tests.
The indirect rapid urease tests, due to their low price, are usually the tests of choice for initial evaluation. These tests utilise the detection of urease through a change of pH that modifies the colour of an indicator from yellow to red. They are commercially available in the form of gels requiring up to 24 hours to read. A strip may be read in up to 1 hour and a liquid as an one minute test. All these tests have an excellent specificity, but their sensitivity is variable, sometimes with many false negatives.
The direct tests, include histological detection, with different stains and cultures with the antibiotic sensitivity tests. Both are of a very high specificity and a high sensitivity but the histological detection depends on the number and localisation of the biopsies, the choice of the stains, the pathologist expertise, and the cultures being performed in well prepared laboratories.
Endoscopy versus non invasive methods
The problem of using endoscopy versus an H.pylori diagnostic non-invasive method as the primary diagnostic tool in a dyspeptic patient is not yet resolved.
Following the "Maastricht Consensus Report", a dyspeptic patient less than 45 years old age, without alarm symptoms and without a family history of cancer, may after a careful clinical examination and a validated positive Hp serology or 13C urea breath test, be treated by a general practitioner without an endoscopy.
In the follow-up after treatment for Hp eradication the endoscopy is only justified if needed for control of the patients lesions. When this is not the case, a 13C urea breath test is the method of choice to control the eradication.
Endoscopy as a therapeutic tool
The endoscope has also been used in Japan to treat Helicobacter pylori infection. A balloon is introducedthrough the endoscope, close to the duodenum. Bicarbonate, amoxicillin, bismuth subnitrate, metronidazole and pronase are then introduced through the tube into the stomach and where it is allowed to remain for two hours. After this period all the drugs are suctioned out. The patients had previously received lanzoprazole and pronase for two days. Kimura et al. (1) presented very good results with this technique, but other researchers must confirm the efficicy of this procedure.
Complications of endoscopy
Endoscopy has been considered a vehicle for transmission of infection with Helicobacter pylori. The use of gloves and a very careful desinfection of the endoscope are needed. Wu et al. verified an 8.5% Hp sero-conversion after manual washing of the endoscope, while none in the mechanical washing group (2).
Trials with the use of an endosheath, a disposable, sheated, flexible gastroscope (3) and with disposable biopsy forceps (4), have been published with good results.
The evolution of endoscopy
The relationships between different types of endoscopy and Helicobacter pylori infections are growing based on new technologies.
For the study of low grade Malt lymphoma with a high rate of cure with Hp eradication, endoscopic ultrasonography is now a routine procedure.
The quantification of Hp infection in gastroduodenal diseases was obtained using the "Endoscopic 13C Urea Breath Test", with a sensitivity of 100% and specificity of 97.3%. This technology uses a baseline breath sample, and endoscopic spraying with phenol red with 100 mg of 13C urea. The colour alterations - red color diffuse- or regional- or unstained, are analyzed followed by a breath sample at 15min.
Many technical developments make the relationship between Hp and endoscopy easier. A few were presented at the American DDW 98, in New Orleans. These included: endoscopic autofluorescense imaging (Weiss), quantitative endoscopy using a novel computerised image processing system (Ligresti), small calibre esophagogastroduodenoscope with an outside diameter of 6mm , and transnasal endoscopy.
It can be seen that there is an important interrelationship between Helicobacter pylori and digestive endoscopy.
Mario Gentil Quina, MD, PhD
Hospital Pulido Valente
1. Kimura K, Ido K, Saifuku K, Taniguchi Y, Kihira K, Satoh K, Takimoto T, Yoshida Y. "A 1-h topical therapy for the treatment of Helicobacter pylori infection". Am J Gastroenterol 1995; 90 (1): 60-63.
2. Wu MS, Wang JT, Yang JC, Wang HH, Sheu JC, Chen DS, Wang. "Effective reduction of Helicobacter pylori infection after upper gastrointestinal+ endoscopy by mechanical washing of the endoscope". Hepato-gastoenterology 1996; 43 (12):1660-1664.
3. Mayinger B, Hochberger J, Strenkert M, Martus P, Han EG. "Endosheath: a disosable, sheathed, flexible gastroscopy: a prospective randomized trial" Gastrointest Endosc 1998; 47(4): AB 55(123) (abstract).
4. Deprez PH,Van Hassel M, Hoang P, Plessevaux H, Fiasse R, Horsmans Y, Vandenbosch D, Geubel A. "Comparative evaluation of disposable versus reusable biopsy forceps costs". Gastrointest Endosc 1998; 47(4): AB 47(92) (abstract).
Percutaneous Endoscopic Gastrostomy Feeding
Percutaneous endoscopic gastrostomy (PEG) is now accepted world-wide as the standard procedure of choice in patients that have any form of pharyngeal or esophageal obstruction to eating. Gauderer first used the modern form of the procedure in a child (1), but then the procedure was adapted so that it was easily used in adults (2). The techniques of Gauderer and Ponsky require the percutaneous passage of a thread or wire which is brought through the mouth from the stomach by an endoscope and then attached to a feeding tube which is pulled back down the esophagus and through the abdominal wall with the tubing positioned and held in place by some form of balloon or baluster. This technique has gained worldwide acceptance. The direct puncture of the abdominal wall and passage of a feeding tube directly through the abdominal wall was described by Russell and colleagues, and also is used by some (3). Whether the pull-through technique or the "push" technique is used the patient is left with direct feeding access into the stomach. This permits formula feeding that is lifesaving.
It has now been shown that early enteral feeding as compared to parenteral feeding clearly reduces postoperative septic complications (4) and is indicated in cerebrovascular accidents, head trauma, neurologic and muscular diseases, post trauma, critical illness, support for cancer patients when indicated, head and neck cancer, inflammatory bowel disease, enterocutaneous fistula, anorexia nervosa, and prolonged intubation with respiratory failure (5,6).
In the patient that is not expected to be ill for a long period of time, access can be obtained by a naso gastric feeding tube. PEG is preferred if there is any difficulty with the swallowing mechanism and long-term enteral feeding is necessary. Whenever significant reflux is suspected or aspiration is a problem because of reflux, then the PEG feeding can be converted to a jejunostomy feeding or a surgical jejunostomy can replace the PEG feeding tube. However, these are far less frequent situations and the majority of patients can be fed either through an enteral tube or a PEG.
Initial evaluation must include:
a careful history of recent nutrient intake;
an evaluation of access;
an evaluation of the metabolic status;
determination of possible multiple organ failure and
the estimated prognosis for length of illness and length of time nutrition support will be needed.
The laboratory evaluation should include an estimate of protein metabolism by tests to evaluate visceral protein, serum albumin and total lymphocyte count. The short half-life proteins prealbumin or retinol-binding protein are extremely helpful. We have found transferrin more difficult to use. With these findings and the physical examination, the nutrition status can be classified into normal, mild, moderate, or severely malnourished for either a marasmic (protein) or kwashiorkor (energy) or mixed depletion.
The 24 hour urea nitrogen output should be used to evaluate for hypermetabolism.
Urine nitrogen loss
= urine urea nitrogen (mg/dl) x daily urine vol. (dl)
The creatinine height index (CHI) can be used to evaluate the skeletal protein mass. Both are easy to do and simply depend on sending a 24-hour urine to the laboratory.
Monitoring of necessity in stress states requires electrolyte and mineral evaluation but nutrition status and protein production can be followed by the prealbumin and 24 hour nitrogen output. Outputs of greater than 8-10 grams of nitrogen indicate hypermetabolism and indicate a greater requirement for protein and energy. In severe stress it is impossible to gain weight. The goal should be to keep up with catabolism and gain stability but not hope to correct malnutrition.
Most hospitals supply a formulary since it is too costly to stock all manufactured products. It is important to appropriately evaluate:
1) energy depending on the nutrition assessment, 0.8-2 gm/kg; and 2) fluid requirements-depending upon the clinical situation 25+ cc/kg, in selecting the formula. It is safest to select a lactose free formula and then determine whether a lcal/lcc or a 1.5 cal/cc formula is wanted. If there is any question of small bowel absorptive capacity, then a formula with medium chain triglycerides (MCT) can be selected.
Most formulas are satisfactory for most clinical situations. However, recent theory (and is should be stressed that good double blinded studies rarely exist) suggest that specific nutrients are helpful in many clinical situations.
In certain organ failures, such as respiratory, carbohydrates should be limited, in renal, protein is limited, and cardiac, sodium is limited, and in liver, protein is limited, and if there is encephalopathy, branch-chained amino acids added. It is also now known that during major stress and trauma the number of calories should be limited since the insulin and carbohydrate body mechanisms cannot handle a high calorie load. Finally, it is now known that glutamine, although not an essential amino acid, is necessary for maintenance of the small bowel integrity; and that argenine, another non-essential amino acid, is necessary to maintain optimal immunologic response. It has also been shown that some fiber is necessary to maintain the integrity of the small bowel and colon. Without glutamine or fiber there tends to be atrophy of the intestine.
It is clear from the past decade of use of enteral and parenteral feedings, that enteral feeding is the support feeding of choice an this can be obtained in patients with the inability to swallow by a PEG access. The formula to be fed depends on the disease state.
Martin H. Floch, MD, PC, MACG
Clinical Professor of Medicine, Yale University
Norwalk, Connecticut USA
1) Gauderer MWL, Ponsky JL, Izant RJ. Gastrostomy without laparotomy: a percutaneous endoscopic technique. J Pediatr Surg 1980; 15: 872-875.
2) Ponsky JL, Gauderer WL. Percutaneous endoscopic gastrostomy-a non-operative technique for feeding gastrostomy. Gastrointest Endosc 1981; 27: 9-15.
3) Russell TR, Brotman M, Norris F. Percutaneous Gastrostomy: A new simplified and cost-effective technique. Am J Surg 1984; 148:132-137.
4) Moore FA, Feliciano DV, Andrassy RJ, et al. Early enteral feeding, compared with parenteral, reduces postoperative septic complications. Ann Surg 1992; 216-222:172-183.
5) Rombeau JL, Rolandelli RH. Enteraò and tube feeding. 3rd Edition 1997 W.B. Saunders Co., Philadelphia, PA.
6) Kirby DF, Delegge MH. Enteral nutrition: the challenge of access. Practical Handbook of Nutrition in Clinical Practice-Kirby, DF, Dudrick SJ. CRC Press Boca Raton, FL 1994: 87-102.
7) Skipper A.: Dieticians Handbook of Enteral and Parenteral Nutrition 2nd Edition; 1998. Aspen Publishing Inc. Gaithersburg, MD.
World Congress of Gastroenterology, Working Party on "Minimal Standards for Endoscopic Disinfection". Report Business Meeting Held in New Orleans, LA, USA, May 18, 1998
Present: Eamonn Quigley, MD (USA-Chair), Habib Ben Khelifa, MD (Tunisia); Nestor Chopita, MD (Argentina); Axel Kruse, MD (Denmark); Kazuei Ogoshi, MD (Japan); Rakesh Tandon, MD, PhD (India).
Excused Absence: Walter Bond, MS (USA); Alistair Cowen, MD, FRACP (Australia); Richard Kozarek, MD (USA).
The following interns were distributed:
Monograph "Clinical Risks of Infection Associated with Endoscopy" by Dr. Cowen
Correspondence to Dr. Quigley from Dr. Bond, draft monograph, "Standard practice for the reprocessing of reusable, heat-stable endoscopic accessory instruments (EAI) used with flexible fiberoptic and video gastrointestinal endoscopes, Correspondence to Dr. Cowen from Dr. Bond regarding his monograph, monograph on "Disinfection, Sterilization and Antisepsis in Health Care", published by the Association for Professionals Infection Control in Epidemiology and draft from CDC on "Creutzfeldt-Jakob disease. Current epidemiology, risk factors and decontamination.
Comments on the draft proposal by Dr. Ben Khelifa
Comments on the experience in Latin America with endoscopic disinfection from Dr. Chopita.
Dr. Quigley summarized the format and the order of presentation for the Working Party in Vienna. The presentation for the Working Party is scheduled between 4-6 pm on Monday afternoon September 7, 1998. Following a brief introduction by Dr. Quigley, three-20-minute presentations will follow as follows:
Walter W. Bond, MS "Microbiological Considerations in Disinfection and Endoscopy"
Alistai Cowen, MD "Clinical Risk of Infection Associated with Endoscopy"
Rakesh Tandon, MD "Endoscopic Disinfection Practices and Recommendations for Endoscopes and Accessories"
1) This will be followed by a discussion within the panel with particular emphasis on experience in different parts of the world and on controversial issues, in particular, the reuse of accessories.
2) This will be followed by an open discussion and concluding remarks by Dr. Quigley.
The remainder of the meeting was taken up with a detailed discussion of Prof. Tandons presentation on "Endoscopic Disinfection Practices and Recommendations for Endoscopes and Accessories". The details of this presentation will be circulated to the members of the committee following receipt of the complete document from Prof. Tandon. The most extensive discussion has surrounded a number of areas which remain controversial.
These are as follows:
The issue of reuse of accessories. While it was agreed that some accessories such as sclerotherapy needles should never be reused, there was some divergence of opinion with regard to the reuse of some common accessories such as biopsy forceps and sphinctertomes, The problems here appears to be in relation to the cleaning of these accessories rather than their disinfection.
The other contentious issue related to the "soaking time" in disinfectant. This is clearly a major issue which has enormous impact, particularly in the developing world. Again, there was divergence of opinion varying from the 10 minutes recommended by the Gastroenterological Nurses Society of Australia and Gastroenterological Nurses Society of Australia to the 20 minutes recommended in Britain and Europe. Indeed, times of up to two hours had been recommended in some reports.
The issued of cleaning, manual vs. machine was discussed in some detail. With regard to manual cleaning, the importance of adequate training of personnel, adequate protection and adequate ventilation were emphasized. Some discussion took place with regard to automated systems, their potential benefits an limitations.
There was consensus that non-immersible instruments should not be recommended.
While most data relates to 2% glutaraldahyde, there are problems with its use, in particular, with the issue of sensitivity in personnel, which apparently has led to its prohibition in Germany and Denmark. What should the Working Party recommended as an alternative? Should this be paracetic acid or are there other possibilities?
Are there some infectious agents that we cannot protect against, in particular, prions and MAI? What should be our statement with regard to these?
What should be our position on alternative methods of disinfection such as thermal, superoxide water, etc? Should these be mentioned if there is insufficient data or availability?
Dr. Quigley undertook to distribute the three draft documents to all of the Working Party once these have been received.
There being no further business, the meeting was adjourned.
Eamonn M.M. Quigley, MD
Chairman, OMED Research Committee
Minutes of the Meeting of the OMED Education Committee. Monday, May 18, 1998. Washington DC, USA
Present: Dr. Waye, M.D. (Chairman), Alessandro Martin, MD, Rikiya Fujita, MD.
OMED conducted a live endoscopy demonstration in Moscow on April 23-24, 1998. The meeting was sponsored by Olympus and Wilson-Cook. The local organizers were Drs. Poddubny and Fedorov. Approximately 400 Russian physicians attended the two-day workshop, where they saw a wide range of endoscopic procedures including ERCP, stone extraction, endoscopic ultrasound, endoscopic mucosal resection and colonoscopic polypectomy. Several lectures were also given by the faculty members, which consisted of Dr. Massimo Crespi, MD (President, OMED); Dr. Alberto Montori, MD (Treasurer, OMED); Dr. Melvin Schapiro, MD (Vice President, OMED); Dr. Aksel Kruse, MD (Denmark); Dr. Paul Fockens, MD (Amsterdam); Dr. J.R. Armengol Mirò, MD (Barcelona) and Dr. Jerome Waye, MD (New York).
The meeting was a great success and was considered a great benefit to all of the registrants who had traveled from all different parts of Russia to attend the workshop. At the present time various locations are being explored for future workshops.
The committee has developed a list of all the guidelines and brochures concerning endoscopy, as well as the video-educational material available throughout the world. The United States, Japan and Australia have the largest number of published guidelines and instructional videotape material concerning endoscopy. The Education Committee will try to adapt currently published guidelines in English for use by the international fraternity of endoscopy. Permission must be obtained from countries which already have developed guidelines. Once the guidelines have been reformulated for their international applicability, the will be published in the OMED bulletin and on the internet site. We thank the individual societies who responded to our request for information.
OMED had made available a 12-pack packet of videotapes from the Sidney World Congress of Gastroenterology and the Los Angeles World Congresses of Gastroenterology.
These videotapes are available without charge upon request by any of the constituent endoscopic societies, and are available for $100 for anyone else who is interested. If interested, contact Dr. Massimo Crespi and specify whether the video format desired il PAL or NTSC.
The Research Committee, in conjunction with the Education Committee, has distributed a questionnaire about "endoscopic practice and priorities throughout the world". We urge all of the constituent societies to answer the survey promptly so that information can be gathered on several topics, including the availability of endoscopy in various parts of the world, the types of endoscopy which are considered to be of greatest benefit throughout the world, and the degree of training required for performing endoscopy. The information from this survey will serve to focus the future thrusts of endoscopy for both educational purposes and research needs.
The Education Committee is currently developing a brochure on the requirements for live courses in endoscopy. This will consist of two parts, a technical portion concerning types of transmission, number of cameras, and the adequacy of facilities. The second part will consist of patient selection, patients safeguards, and the role of the nurse/assistant during live demonstration.
OMED has its own web page, which is found at "hyperlink http://www.uni.net/omed ". The e-mail address is OMED @uni.net.
Jerome D. Waye, MD
Chairman OMED Education Committee
U.S. Guidelines Recommend Population Screening for Colorectal Cancer
Recently developed evidence-based guidelines published in the United States recommend that primary clinicians screen their at-risk patients for colorectal cancer (1-3). High-quality scientific studies indicate that widespread adoption of the recommendations contained in these guidelines would substantially reduce the mortality and morbidity caused by colorectal cancer in high-incidence countries. The only screening methods that have been directly evaluated in prospective trials and case-control studies are fecal occult blood testing (FOBT) and periodic flexible sigmoidoscopy.
Fecal occult blood test screening has been extensively studied in five prospective, controlled trials involving over 320,000 participants, two in the U.S. and three in Europe. Four of these have recently reported a significant reduction in mortality from colorectal cancer as a result of screening, ranging from 15% to 43%. In addition, all five of the trials have shown that cancers detected by screening are at a more favorable stage at the time of surgery, and patients with screen-detected cancers have improved survival.
Flexible sigmoidoscopy is highly accurate for detecting polyps and cancers in the left colon. The procedure is well-tolerated and sufficiently inexpensive so that it can be used as a population-based screening test. There are not yet any completed controlled trials that prove the efficacy of screening. However, cohort and case-control studies have demonstrated a reduction in mortality from distal cancers of 60%-80% as the result of screening with rigid proctoscopy. Both case-control and observational studies indicate that a negative sigmoidoscopy does not need to be repeated for at least five years.
Based on these highly consistent and compelling data, current evidence-based guidelines separately developed or revised by the U.S. Preventive Services Task Force, a consortium of five U.S. GI medical and surgical societies, and the American Cancer Society, now recommend annual FOBT screening plus flexible sigmoidoscopy about every five years for asymptomatic, average-risk men and women beginning at age 50. Screening with the combination of both tests appears to correct most of the limitations of either test used alone. Colonoscopy is the diagnostic procedure of choice for those with a positive screening test. Scientific studies and substantial clinical experience suggest that widespread adoption of these recommendations would result in the prevention of many cancers by the detection and resection of adenomatous polyps, and in the ultimate cure of most early cancers. Such screening could lower the death rate from the disease in high-risk countries by over 50%, and could substantially reduce related pain, suffering, and cost.
Screening an entire population over the age of 50 admittedly would be very expensive. Projections of the total cost of screening, however, often do not consider realistic estimates of compliance or a number of cost-saving strategies that are possible in clinical practice. The public and health care payers should also understand that the cost of missing an early curable cancer or of failing to prevent the disease by resecting premalignant adenomas may be as great or greater than the cost of screening. Health economists from the U.S. Congress and the U.S. National Cancer Institute recently reported that screening for colorectal cancer in high-risk countries such as the United States is highly cost-effective and "represents a relatively good investment for society" (4).
Although we now have effective screening tests, accurate methods of diagnosis, curative treatment, and proper surveillance for high-risk groups, the critical final prerequisite to the prevention and early detection of colorectal cancer is compliance. Educational programs designed to increase awareness about the impact of colorectal cancer, and about the value of screening and surveillance for the disease are currently underway in many countries. These programs are designed for both the general public, and for primary clinicians and health care payers that are in the best position to provide these important services.
1. Guide to Clinical Preventive Services, Second Edition. Report of the U.S. Preventive Services Task Force. Washington, DC, Department of Health and Human Services, l995.
2. Winawer SJ, Fletcher RH, Miller L, et al. Colorectal cancer screening: Clinical guidelines and rationale. Gastroenterology 1997; 112:594-642.
3. Byers T, Levin B, Rothenberger D, et al. American Cancer Society guideline for screening and surveillance for colorectal polyps and cancers. CA-Cancer J Clin l997; 47, No 4:2-8.
4. Wagner JL, Tunis S, Brown M, et al. The cost-effectiveness of colorectal cancer screening in average-risk adults. In: Young G, Levin B, Rozen A, eds. Prevention and Early Detection of Colorectal Cancer. London, WB Saunders, l996, pp. 321-356.
John H. Bond, MD
Chief, Gastroenterology Section, VA Medical Center
1st Baltic States Workshop on Advanced Endoscopy
June 25-27, 1998, the I Baltic States Workshop on Advanced Endoscopy took place in Tallinn, Estonia, organized by the national gastrointestinal endoscopy societies of the three Baltic States - Estonia, Latvia an Lithuania. It was the very first gastrointestinal endoscopy training course in the Baltic States, set up under the auspices of the European Society of Gastrointestinal Endoscopy (ESGE).
Today, when the I Baltic States Workshop on Advanced Endoscopy has become a historic event already, it would be to the point, to recall the beginning of the cooperation between the ESGE and the Baltic States: the landmark was 1992, when at the II UEGW in Athens, the endoscopy societies of Estonia and Lithuania joined the ESGE. During the VI UEGW in Birmingham in 1997, it was decided to set up a workshop in one of the Baltic States. It was then and there, when the representatives of the endoscopy societies of Estonia, Latvia and Lithuania - Drs. M. Eisen, I. Tolmanis and K. Adamonis - approached the ESGE President, Professor F. Hagenmüller and the Governing Board with their common proposal about an endoscopy workshop. This decision may well be called history-making, as the ESGE training-and educational-courses area expanded considerably: formerly, only the Central-European countries (Poland, the Czech Republic, Slovakia, Hungary and Slovenia) were involved; now also the Baltic States were included.
The main objective of the I Baltic States Workshop on Advance Endoscopy was to render a possibly large audience of the Baltic States endoscopists an overview of the updated developments and possibilities of the modern endoscopy. Setting up such a training course in the Baltic States is, doubtless, in harmony with the current demands, as Estonia, Latvia and Lithuania are in the process of the EU accession, which means, that the integration should proceed in all the domains, including medicine at large and gastroenterology/gastrointestinal endoscopy in particular, with the requirements to introduce the unitary quality standards.
The setting up of the Workshop in one of the Baltic States was the first experience of its kind, an, more than that, the very form of the Workshop was unique and non traditional. The ESGE Governing Board had come to the conclusion, to organize the Workshop in Tallinn, based on the videopresentations, only, which made a cardinal difference from the former experience. This was a novel and interesting innovation, with the purpose of presenting in a most intensive way the updated endoscopy methods and terminology; the participants had a unique opportunity for direct contacts with the recognized experts; they could communicate; check their personal skills and obtain new ideas.
This kind of a novel training- and education initiative was a challenge to the Workshop Organizing Committee, as the dynamic and fluent course was the ultimate prerequisite for the success of such videopresentations. The Organizing Committee's choice for the Workshop venue was the National Library of Estonia in the Tallinn city center, with its high-technology-equipped Conference Hall.
The Workshop program was varied and the time schedule intense. The following topics were discussed: the endoscopic treatment of the esophageal diseases (F. Hagenmüller, J.F. Rey), gastric pathology and the upper gastrointestinal haemorrhage (J. Rattan, A. Axon), pancreatobiliary pathology (A. Kruse, A, Nowak, J.R. Armengol-Mirò, J.F. Rey, J. Rattan), pathology of the colon (J.F. Rey, J.R. Armengol-Mirò). The OMED Acting President Professor M. Crespi presented an overview on the education in gastroenterology and gastrointestinal endoscopy in Europe (European Diploma of Gastroenterology) and the Minimal Standard Terminology for Endoscopy. The ESGE Secretary General concentrated on the EUS of the gastrointestinal diseases and Professor A. Kruse on the radiological approaches in therapeutic endoscopy. Professor F. Hagenmüller shared information also on the ESGE Pan-European Public Awareness Campaign on the Management of CRC and GERD.
140 physicians from the Baltic States attended the Workshop; the participants from Poland, the Czech Republic, Croatia, Slovakia, Germany, Denmark and the Ukraine has also joined in. The Workshop Opening Ceremony was in the Tallinn Town Hall, where traditionally the eminent guests of the capital are received. At the Opening Ceremony, surrounded by the 700-years-old walls of the Town Hall, the Workshop participants were welcomed by Dr. J. Rüütman, the Chancellor of the Ministry of Social Affairs of the Republic of Estonia and Dr. V. Keldrimaa, a representative of the Tallinn City Government. On part of the ESGE, the participants were greeted by Professor F. Hagenmüller and on part of the Workshop Organizing Committee by Dr. M. Eisen. A special event during the Opening Ceremony was handing over a present to Professor F. Hagenmüller by Dr. M. Eisen: a Tallinn-made blue-white flag with the ESGE logo.
It should be emphasized that this year the 750th anniversary of the introduction of the Ius Lybyckense in Revalia was celebrated in Tallinn, which is one of the Hanseatic towns, situated on the shores of the Baltic Sea.
The representatives of the Olympus Co., the Workshop General Sponsor, were also present: from Olympus-Tokyo, Mr. Y. Takashashi and Mr. H. Nakano; from Olympus-Moscow Co., Mr. Y. Sakagushi and Mrs. S. Karpova; from Olympus-Europe, Mr. K. Spencer. The representative Workshop was a good opportunity for the Olympus Co. experts to meet the Chairmen of the Gastrointestinal Endoscopy Societies of the Baltic States. The presidents of the Estonian, Latvian and Lithuanian Societies expressed their gratitude tot he Workshop General Sponsor for the extensive support. The topics discussed were the near future accession of the Baltic States to the EU and their rapidly developing economic and cultural contacts with the European countries. The parties shared their opinions an made proposals for the further successful activities of the Olympus Co. in the three Baltic States.
Summing up, all the I Baltic States Workshop on Advanced Endoscopy participants considered the Workshop to have been a success, rendering novel ideas for the organizational and the didactic viewpoints. This faculty justified the Workshop motto: Only the best is good enough for the education in gastrointestinal endoscopy.
Mart Eisen, MD
President Estonia Society of Gastrointestinal Endoscopy
Chairman Organizing Committee
1° Baltic Workshop on Advanced Endoscopy,
First Clinical Application in Telesurgery at the 6th World Congress of Endoscopic Surgery in Rome, June 1998
Based on recent scientific and clinical experience of the first applications in telesurgery, the 6th World Congress of Endoscopic Surgery in Rome added two special sessions to include presentations by Professor Guy-Bernard Cadiere, of St. Pierre Hospital in Belgium, and Doctor Anno Diegeler, of the Leipzig Heart Center in Germany. These two surgeons were invited to present their initial results and experience using the Intuitive computer-enhanced surgery system.
Professor Cadiere performed the worlds first computer-enhanced Nissen Fundoplication procedure and Doctor Diegeler and his team performed the worlds first videoscopic coronary artery bypass surgery.
The World Congress of Endoscopic Surgery provides a scientific forum in which to debate and exchange scientific experiences in the field of Minimally Invasive Surgery. While moving toward the next millennium, technologies such as this system will be one of the most significant advancements in endoscopy, helping to redefine minimally invasive surgery as we know it today.
Intuitive is developing a computer-enhanced minimally invasive surgery system that uses proprietary electronics, advanced robotics, and enhanced visualization to greatly improve surgical technique and take surgical precision far beyond what is possible today.
The system is a new surgical technology intended to eliminate the major obstacles to widespread adoption of Minimally Invasive Surgery. It is designed to transform a broad range of open procedures to Minimally Invasive Procedures by making MIS more precise and easier to perform. Using state-of-the-art computing, sophisticated software and highly-specialized micro-surgical instruments, this system combines the natural hand movements used in traditional open surgery, with the less traumatic approach of Minimally Invasive Surgery thereby delivering the best of both techniques. Using this system, surgeons will perform procedures seated at the console while viewing a high-resolution 3-D video image of the surgical field.
The surgeons hands rest below the monitor and hold instruments that provide the flexibility of those used in open surgery. Highly-specialized technology simultaneous transfers the surgeons exact hand movements made at the console to precise microsurgical movements of the instruments at the operative site.
With this remote control it is nowadays possible to operate with precision and these surgical procedures can be done based on scientific and clinical experience of the application in telesurgery.
Alberto. Montori, MD
President 6th World Congress of Endoscopic Surgery
OMED Presidential Poster Gold Medal Award in Therapeutic Endoscopy
World Congress of Gastroenterology '98
Title: Endoscopic Injection of Bleeding Esophageal Varices Using Poly-N-Acetyl Glucosamine Gel in the Canine Portal Hypertention Model.
Authors: Kulling D., Vournakis JN., Woo S., Demcheva MV., Tagge DU., Rios G., Finkielsztein S., Hawes RH.
Institutions:Division of Gastroenterology, Department of Internal Medicine, University Hospital Zurich, Zurich, Switzerland.
Digestive Disease Center, Medical University. of South Carolina, Charleston, SC, USA
Center of Molecular and Structural Biology, Medical University of South Carolina, Charleston, SC, USA
Marine Polymer Technologies, Inc., Danvers, MA, USA.
Financial support: This study was supported by a 1997 Endoscopic Research Award
American Society for Gastrointestinal Endoscopy and the American Digestive Health Foundation (to Daniel Kulling, MD) and by Marine Polymer Technologies, Inc., Danvers, MA.
By and with the contribution of Èulogos and UniNet.
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