Acetic acid-enhanced magnification endoscopy in the diagnosis of specialized intestinal metaplasia, dysplasia and early cancer in Barrett's oesophagus.

BACKGROUND: Barrett's surveillance is prone to sampling error. Aim To determine whether enhanced magnification endoscopy using acetic acid instillation improves diagnostic accuracy of specialized intestinal metaplasia/dysplasia in Barrett's oesophagus. METHODS: We examined the detection rate of the specialized intestinal metaplasia/dysplasia in 64 consecutive patients with Barrett's oesophagus using acetic acid to enhance mucosal pit patterns. Histology was compared with the previous findings at recent conventional surveillance in 62 patients. We also examined the inter-/intra-observer agreement in the assessment of the enhanced magnification endoscopy pit pattern findings. RESULTS: Histology revealed columnar-lined oesophagus in six (9%) patients, specialized intestinal metaplasia in 49 (77%), low-grade dysplasia in five (8%), high-grade dysplasia in one (2%), and adenocarcinoma in three (5%). There was discordance between the histologic findings from conventional surveillance with random biopsy. Fifteen patients (24%) had a histological upgrade with enhanced magnification endoscopy. There was a high detection rate of specialized intestinal metaplasia even in short segment Barrett's oesophagus (74%), and additionally, there were two cancers, one with 2-cm Barrett's oesophagus and one ultra-short (1 cm). The mean kappa values for inter- and intra-observer agreement in assessing the pit patterns were 0.571 (0.041) and 0.709 (0.038), respectively. CONCLUSIONS: Enhanced magnification endoscopy allows clear visualization of the epithelial pit patterns within Barrett's oesophagus, and targeted biopsy results in a high yield of specialized intestinal metaplasia and dysplasia.

How good is zoom endoscopy for assessment of villous atrophy in coeliac disease?

BACKGROUND AND STUDY AIMS: The advent of magnification endoscopy may allow the macroscopic detection of unrecognised villous atrophy in patients with unsuspected coeliac disease. In addition, it may also be possible to use this method to assess the degree of villous atrophy. The aim of this study was to determine the accuracy of zoom endoscopy for the macroscopic evaluation of villous atrophy, in comparison with histological evaluation. PATIENTS AND METHODS: The zoom endoscope provided a magnification capability of x 115. A scoring system (Z score) was devised for grading the appearances of villous atrophy: "Z1" for normal mucosa, "Z2" for stunted villi, "Z3" for markedly stunted villi (with ridges and pits) and "Z4" for a flat mucosa. A total of 53 consecutive patients with treated coeliac disease were followed up over almost 2 years using the Olympus GIF-Q240Z zoom endoscope; a total of 80 procedures were carried out. Four biopsies from the second part of the duodenum were taken from each patient for histological assessment. Histological assessment of villous atrophy was made by a pathologist blinded to the Z score. The correlation between the Z score and the histological score was assessed using the weighted kappa method. RESULTS: The kappa score for the correlation between the macroscopic assessment of villous atrophy and the histology was 0.631, indicating fair to good reproducibility. Agresti's method revealed a very strong baseline association between the two methods ( P < 0.001). Zoom endoscopy had a positive predictive value of 83 % and a negative predictive value of 77 % in detecting villous atrophy. CONCLUSIONS: Our findings suggest that zoom endoscopy may be valuable in assessing the degree of villous atrophy. However, further studies are needed to assess its efficacy in routine practice as a screening or case-finding tool.