Esophageal stricture induced by an ultraslim upper endoscope in a novel rabbit model of corrosive injury.

Abstract

OBJECTIVE: Benign esophageal strictures are regularly encountered problems in

clinical practice. The management of refractory benign esophageal stricture,

which fails to establish adequate food passage despite multiple dilatation

sessions, has been considered challenging. Experimental animal models are

essential for the development of effective treatment methods. The aim of this

study was to establish a new animal model of benign esophageal stricture using

rabbits. MATERIAL AND METHODS: Corrosive injury of the esophagus was induced by

administration of 1 ml of 1.5% sodium hydroxide in eight rabbits using an

ultraslim upper endoscope equipped with a 5-Fr polytetrafluoroethylene tube and

5-Fr balloon catheter. Two weeks after corrosive injury, endoscopic examination

was performed to confirm the state of the injury site. Four weeks after corrosive

injury, the esophageal stricture was assessed by endoscopy and esophagography.

All animals were then euthanized. RESULTS: Two weeks after corrosive injury,

endoscopic examination showed that ulceration had been induced. Four weeks after

corrosive injury, endoscopic, radiologic and gross examinations showed that

esophageal stricture had been induced without complications in all animals. The

esophageal lumen diameter was reduced by an average of 51.8% (range,

48.3%-57.2%), and the mean stricture length was 25.7 mm (range, 20.1-29.3 mm).

Microscopic examination revealed focal ulceration and submucosal thickening

secondary to fibrosis. CONCLUSIONS: Rabbit esophageal stricture induced by

endoscopic delivery of a small amount of low-concentration sodium hydroxide is a

relatively simple, safe, and reproducible animal model. This model may be useful

in the development of new treatment methods for esophageal stricture.