Enhanced magnification endoscopy: a new technique to identify specialized intestinal metaplasia in Barrett's esophagus

Background: Specialized intestinal metaplasia (SIM) in Barrett's esophagus (BE) is not identifiable by standard endoscopy. Acetic acid instillation en hances the ability to detect columnar epithelium at the squamocolumnar unio n. Enhanced magnification endoscopy involves the combined use of magnificat ion endoscopy with acetic acid. This study assessed the value of enhanced m agnification endoscopy in detecting SIM in patients with BE. Methods: Patients undergoing endoscopic surveillance because of short segme nt BE without dysplasia underwent enhanced magnification endoscopy with 1.5 % acetic acid instillation, Standard endoscopy was followed by magnificatio n endoscopy and repeated after acetic acid spraying. Surface patterns were characterized prior to and after acetic acid spraying. The observed surface patterns were compared with histology results. Results: Forty-nine patients, 9 women and 39 men, with a mean age of 50.5 y ears were studied, One was excluded because of unclear definition of the su rface pattern. Enhanced magnification endoscopy detected 4 different mucosa l surface patterns: I, round pits; II, reticular; III, villous; and IV, rid ged. A total of 129 areas were examined. Standard endoscopy identified an e ndoscopic pattern in 1.5% of the areas, standard endoscopy and acetic acid in 8.5%, magnification endoscopy alone in 38%, and enhanced magnification e ndoscopy in all 129 endoscopic areas. The yields for detecting SIM accordin g to endoscopic patterns were as follows: pattern I, 0%; II, 11% (odds rati o 0.5, p = 0.54); III, 87% (odds ratio 36, p = 0.001); and IV, 100% (odds r atio 14, p = 0.015). Conclusions: Enhanced magnification endoscopy is an accurate method of pred icting SIM in BE, The simplicity of the technique and its ability to identi fy characteristic endoscopic patterns with outstanding clarity and resoluti on that correlate with histologic identification of specialized intestinal metaplasia make enhanced magnification endoscopy an excellent method for th e evaluation of patients with BE.