Gastrointestinal endoscopy in dogs

Endoscopy is now widely available for the investigation of gastrointestinal disease in dogs; Franck Jolivet and Olivier Dossin present a practical, case-based paper that illustrates the versatility of the endoscope, along with some useful tips on how to best use this diagnostic option in practice.

Introduction

Endoscopy is a versatile and minimally invasive technique used to visualize the gastrointestinal (GI) lumen, perform biopsies for further analysis such as histopathology or bacterial analysis, and to deliver treatment for problems such as strictures, polyps or foreign body removal. Although complications of routine endoscopic procedures are rare (1), endoscopy must be performed after a thorough work-up and should never be a substitute for a complete history, physical examination, appropriate laboratory procedures and other diagnostic imaging. It is especially important to note that endoscopy and endoscopic biopsy are not always indicated, especially in animals with chronic GI disease, without appropriate therapeutic trials (e.g., deworm-ing, dietary modification, antimicrobial trial). In conjunction with other diagnostic modalities, endoscopy can be both a powerful diagnostic tool for many GI disorders in dogs and an invaluable therapeutic tool, particularly for the retrieval of gastric or esophageal foreign bodies. This article will consider the benefits of endoscopy in dogs using five case studies. Interventional endoscopy and laparoscopy are beyond the scope of this paper.

Endoscopic equipment

Standard GI videoendoscopy equipment consists of a flexible endoscope, a light source, a videoprocessor, a monitor and an air pump; a videorecording system is frequently connected to the system ( 2 ) ( 3 ). A variety of instruments and accessories are also available, including biopsy forceps, cytology brushes, aspiration/injection needles and foreign body forceps/baskets ( 4 ). The main considerations when choosing an endoscope are its length, the outer diameter of the scope, and the diameter of the accessory channel. In dogs, a scope of 8-9 mm diameter and 100-140 cm in length is the most versatile for routine GI endoscopy ( 2 ) ( 5 ), although in the largest breeds this might be too short to pass the ileo-colonic sphincter or the pylorus. It is usually better to select a scope with an accessory channel with a 2.8 mm diameter, which will accept the largest biopsy forceps; this enables a better biopsy quality.

Endoscopic findings should be recorded (ideally including pictures) immediately after the procedure, and standardized reporting forms have been recently proposed (see: www.wsava.org/guidelines/gastrointestinal-guidelines). [...]