2.0 Introduction

Since computers became more readily available and relatively inexpensive, there has been increasing interest in their use for recording the findings at endoscopy. The advantages are that it is possible to search any database created, perform statistical analysis, and avoid the need for hand-written or typed reports. Around the world, a considerable number of endoscopy record systems have been developed but there has been no standardization of the terminology used. As a result, a golden opportunity has been lost for sharing and comparing data collected from different centers.

Following a meeting on "Computers in Endoscopy" organized by Pr. M. Classen in Munich in 1991, it became apparent that this important problem needed resolution. The European Society for Gastrointestinal Endoscopy decided to resolve the issues. A Committee was established under the chairmanship of Pr. M. Crespi and included a number of experts from Belgium, France, Germany, Hungary, Italy, Spain and the United Kingdom. Dr. Maratka from Czech Republic was invited to join the Committee because of the work that he had already done on endoscopic terminology for the World Organization for Digestive Endoscopy (OMED). At an early stage, it was felt important that the other World Zones be represented and representatives from the USA and Japan were added to the Committee. Additionally, the three major endoscope manufacturers (Fujinon, Olympus and Pentax) and the publisher Normed-Verlag were invited to join the committee as it was imperative that industry should be involved in this work as they were developing their own systems and compatibility between these was regarded as vital if the opportunities for sharing data were to be optimized. It was also important that these companies be involved in discussing other aspects, such as image capture, storage and transfer.

Between 1992 and 1993, a series of meetings of this Committee were held, concluding with a joint meeting of the ESGE group and the Computer Committee of the American Society for Gastrointestinal Endoscopy (ASGE). At this time, the work was reviewed and modified and the Committee was constituted as the Working Party for this report for the World Congresses of Gastroenterology and Digestive Endoscopy.

The list of terms proposed has drawn heavily upon the original and detailed work performed by the OMED committee under the chairmanship and guidance of Pr. Z. Maratka. When published in full, the terms selected will be preceded, when applicable, by the OMED code number, as published in "Terminology, Definitions and Diagnostic Criteria in Digestive Endoscopy; 3rd Edition. This will provide a reference for users unfamiliar with the words employed. This reference provides a definition of the term together with its language equivalents, if English is not the user's natural language. Currently there are editions of this book in French, German, Italian and Spanish, and several other languages.

In order to obtain Committee consensus, it was necessary to include a few "terms" that were not originally included in the OMED classification. This was because these words were in such common use that the Committee felt that they had to be included if the database created was to prove acceptable to an average user. Similarly, the list of "attributes" attached to any term to provide greater detail was restricted to those that were most commonly employed. As a result, the amount of detail provided may prove insufficient for some users of the terminology, particularly those wishing to record considerable detail for "research" purposes. However, it was agreed that any endoscopist wishing to record extra-detail could do so, providing the computer system developed contains the "minimal terminology". For this reason, only terms commonly used to describe a lesion have been included. Unreliable attributes, such as distance from the teeth for a gastric lesion, and from the anal margin for a colonic lesion located above the rectum, have not been included.

MST version 1.0 formed the basis for prospective testing of the Terminology in Europe and the United States. This testing was funded by the European Commission through the Gaster Project and the American Digestive Health Foundation. The results of this prospective testing forms the basis for modifications made to version 1.0 that are presented here. The changes have been reviewed and accepted by the ESGE and ASGE Committees and constitute the Minimal Standard Terminology version 2.0. Specific software was developed for testing which allowed endoscopists in univeristy hospitals and private practice to prospectively record endoscopic cases using the Minimal Standard Terminology version 1.0In Europe, the software was designed to provide the endoscopists with a translation into the main European languages (English, French, German, Italian, Spanish) and the possibility of performing the final analysis independent of the original language in which the cases had been recorded.

2.1 General organization

The principles by which the list of terms is described on page 21. In the same paragraph, is explained the structure of the terms, attributes and attribute values.

2.2 Decisions on difficult terms.

The Committee paid particular attention to which terms to include and which to avoid because some lead to ambiguity, misuse or were considered to be redundant. The selection of a term had to take into account the need for a very precise descriptive word and the acceptability of these words amongst physicians from different countries with different native languages. There was also the problem of different, but closely related, words used more commonly in one language than in another. This led to the selection of terms based on English with some minor differences between Europe and the United States. Translations of these terms in other languages should be based on the official translations found within the OMED terminology.

2.2.1 Stenosis

A narrowed segment of the gut can be described in a number of ways: "narrowed", "strictured", "stenosed", "compressed". All of these terms have been grouped in the terminology under the generic term "stenosis". The same term has been used to describe the narrowing of a sphincter which either prevents the passage of the endoscope or requires force to traverse it. Functional terms such as "spasm" have been avoided because of their subjective nature. Once a stenosis has been described it is qualified by attribute values: "extrinsic", "intrinsic benign" or "intrinsic malignant", based on the probable cause. In the case of an extrinsic compression, where actual stenosis of the lumen does not occur, e.g. the aortic prominence, the term "stenosis" should not be used.

2.2.2 Red mucosa, erythema, congested mucosa, hyperemia

During prolonged discussions on which terms to include in the minimal standard terminology, it became apparent that all of the above terms were used to define roughly similar lesions or mucosal patterns. It was finally agreed that it was only necessary to distinguish between an erythematous and a congested mucosal appearance. Erythematous mucosa being defined as either a focal or diffuse reddening of the mucosa without any other modification; congested mucosa, on the other hand, being defined as a combination of erythema with an edematous, swollen or friable mucosa. Due to the large overlap between these terms, it was agreed that hyperemia was equivalent to erythema and edematous was equivalent to congested mucosa. So these words could be used as an alternative but not added simultaneously to the number of terms used.

2.2.3 Mucosal sclerosis

This term is used to describe post-sclerotherapy mucosal and submucosal changes that can occur in the esophagus after endoscopic sclerotherapy of esophageal varices. Although the term "fibrosis" primarily describes histological changes, it is so frequently used that it was accepted as equivalent to sclerosis. Testing studies showed that mucosal sclerosis was also used to describe the aspect of a sclerotic lower third of the esophagus in the absence of any antecedent variceal therapy. To overcome this dual meaning of the term, an attribute has been added to specify whether it is spontaneous or post-therapeutic.

2.2.4 Erosion, aphtha

In the original OMED terminology, the term "erosion" had been avoided because it was considered to be imprecise and required histological confirmation; "aphtha" had, therefore, been the preferred term. During extensive discussions, the Committee had come to the conclusion that the term "erosion" was in such common usage in many languages that it had to be included amongst the minimal standard. However, a strict definition of this term is required. "Erosion" is defined as a small superficial defect in a mucosa, of a white or yellow color, with a flat edge. This may bleed, but the term should only be used when the mucosa is clearly seen and is not covered by blood clot.

In the colon, it was decided to retain the term "aphtha", as it was agreed that aphthae were identified more frequently in this area and were a recognized diagnostic feature of "Crohn's disease". In this context, aphthae are defined as yellow or white spots, surrounded by a red halo and frequently with a spot in the center. Aphthae are frequently seen within a congested or erythematous mucosa and are often multiple.

2.2.5 Tumor, mass

In the original Committee recommendations, the word "tumor" was used to describe any lesion which appears to be of a neoplastic nature but without any attempt to say whether it is benign or malignant. It is not used for small lesions such as granules, papules etc…, nor for other protruding lesions such as polyps, varices or giant folds. The conjoint ASGE review revealed difficulty with this term as, in the USA, a patient might assume that a tumor is a malignant lesion. For this reason, it has been agreed that the term "mass" could be used as an equivalent term when needed.

2.2.6 Angioectasia

Both telangiectasia and angiodysplasia have been grouped under this generic term. This is because there are no precise visible diagnostic criteria which will allow one to distinguish between these two lesions. This term can also be applied to congenital and acquired vascular malformations within the mucosa of the gastrointestinal tract.

2.2.7 Scar

The term "scar" is preferred to the term "fibrosis" as the latter implies a histologically confirmed process. The cicatricial aspect of the mucosa after healing of an ulcer or following a therapeutic maneuver (e.g. injection sclerosis; laser photocoagulation) seems to fit better with this word.

2.2.8 Occlusion, obstruction.

According to the definition contained in the OMED terminology, "obstruction" means blockage of a tubular structure by an intraluminal obstacle (e.g. foreign body) while "occlusion" implies complete closure of the lumen by an intrinsic lesion of the wall (e.g. fibrosis from a healing duodenal ulcer causing pyloric stenosis). Although obstruction and occlusion can be either partial or complete, the use of these two terms was felt to be confusing and created difficulties when translated into other languages. It was, therefore, decided to restrict the use of the term "obstruction" to 2 situations: (i) the presence of an exophytic tumor in a tubular organ; (ii) the findings in the biliary tree and in pancreatic ducts at X-ray examination during an ERCP. This term covers partial or complete hold-up to the passage of contrast into a duct, whatever the cause of this obstruction (e.g. stone, tumor, foreign body). In the case of obstruction of a tubular organ, this obstruction would be described as partial or complete, depending whether a lumen is present or not.

2.2.9 Ulcerated mucosa.

Endoscopists felt that there may be a conceptual distinction between ulcers that are multiple and mucosa that was ulcerated. Testing indicated that a term describing a diffusely ulcerated mucosa in one concept was frequently used, both in the US and in Europe and it appeared that the endoscopists using this term considered this global pattern of the mucosa as rather typical of ulcerative colitis. Therefore, Ulcerated mucosa was introduced in version 2.0. It is emphasized that this term should be used only in the case of a diffusely ulcerated mucosa when the endoscopist distinguishes this concept from "ulcers" that are multiple. However, it is recognized that the use of this term needs to be evaluated in prospective trials, in order to better define its meaning and whether it is a distinct concept from the term "ulcer".

2.3 Location of Lesions: Principles and Consensus Decisions.

2.3.1 General principles.

Although location of a lesion is a key point in any description of a term, specifications such as distance from the teeth or anal verge could be imprecise in certain organs or sites. It was, therefore decided that such "distance specifications" should only be employed where the organ being examined allows this to be relevant (e.g. esophagus at upper GI endoscopy and rectum at colonoscopy).

In some cases, multiple recording of sites should be implemented, as far as some multiple lesions need specification of the site for each of them or when the precise location of a lesion needs the use of two terms (e.g. in the stomach, a tumor growing on the "lesser curvature" of the "antrum").

2.3.2 Decisions on difficult locations.

Among the many locations defined in the terminology, there were some that were only agreed after prolonged discussion. The arguments for these decisions were as follows:

2.3.2.1 Cardia, Hiatus, Lower Esophageal Sphincter.

There are many terms that have been used to describe the area of the esophago-gastric junction (Figure 1A). Although these can be carefully defined, they are often assumed to be synonymous and are used incorrectly as a result. To clarify this situation, it was decided to omit the term "lower esophageal sphincter" from the list of locations within the esophagus section as it is difficult to identify, being a functional entity, and cannot be used as a fixed point for locating an individual lesion. However, this term was included as a specific term within the category "Lumen", to enable the user of a system to record its appearance (e.g. gaping or hypertonic).

 

Figure 1A.

The "esophago-gastric junction" implies a transition from the esophagus to the stomach but is usually used for the mucosal junction (Z-line). It has, therefore, been avoided as a location, because it may be located apart from the exact junction between the esophagus and the stomach.

"Hiatus" describes the orifice in the diaphragm which can be difficult to identify and tends to cause difficulties when defining a hiatus hernia. For these reasons, the term "cardia" was chosen to describe the whole of this region. Following initial testing of the terminology, it became apparent that this caused problems when describing a hiatus hernia. Initially, it had been agreed that the size of any hernia present would simply be recorded as "small" or "large". However, many users wanted to describe the size of a hiatus hernia as the distance between the Z-line and an anatomical reference defining the passage of the diaphragm. Likewise, the length of a Barrett's esophagus was defined as the distance between the transition from the esophageal mucosa to gastric mucosa (Z line) and an anatomic reference for the end the smooth tube-like esophagus. For this reason, the term "hiatal narrowing" was included within the version 1.0 of the terminology. This would also allow better specification of the length of a Barrett's esophagus and possibly of hiatus hernia.

However, the testing of MST version 1.0 indicated that the location cardia and the terms Z line and Hiatal narrowing were poorly undertsood by the users. To clarify the description the following modifications were made:

Figure 1B.

2.3.2.2 Gastric Fundus, Body and Antrum.

Fundus is used to describe the anatomical part of the stomach that lies under the diaphragm on a barium meal examination. In the OMED terminology the term "fundus" is regarded as confusing and the term "fornix" has been preferred to describe the upper area of the stomach examined during a reverse maneuver. In the recommended minimal standard terminology, the term "fundus" has been used as it is so commonly employed that it was felt undesirable to remove it.

The gastric body is defined as the area of the stomach above the angulus which is usually lined by folded gastric mucosa. The antrum is defined as the distal part of the stomach usually lined by flat mucosa.

2.3.2.3 Biliary Tree.

A problem occurs in the description of the biliary tree. The anatomical divisions "common hepatic duct" and "common bile duct" within the extrahepatic duct are defined by the insertion of the cystic duct. This division makes no allowance for the variability in this junction and leads to considerable confusion when trying to identify the site of a lesion within the extrahepatic duct. For this reason it was decided to identify a site called the "main bile duct", which would encompass both the common hepatic and common bile duct, locating any lesion as being within the upper, middle or lower third of this duct (Figure 2).

The major intrahepatic ducts were identified as right and left hepatic ducts from the junction at the porta hepatis and their first sub-division. All other ducts within the liver are called intrahepatic ducts.

 

Figure 2.

 


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