Colonoscopy, as the gold standard for detecting colorectal neoplasia, has lost some of its glitter, according to a US expert.1 Lieberman was commenting on a multicentre trial in the US, which found that, compared with same-day, state-of-the-art 3-D virtual colonoscopy, optical colonoscopy missed 55 of 511 polyps detected in a series of 1233 asymptomatic patients; 21 of the polyps measured at least 6mm, one being an adenocarcinoma.2 The adenomas missed were usually on the proximal side of a colonic fold or near the anal verge. Virtual colonoscopy also missed adenomas detected by optical colonoscopy, underscoring the complementary nature of the two techniques. Nevertheless, Lieberman says optical colonoscopy remains the pre-eminent method for diagnosing and treating colonic neoplasia.

