• Barrett’s oesophagus
• dysplasia
• endoscopy
• oesophageal adenocarcinoma
• imaging

Although the early detection of high grade dysplasia, the precursor of oesophageal adenocarcinoma, remains a primary task in the management of patients with Barrett’s oesophagus, several other key end points of screening and surveillance need to be considered (table 1). As dysplasia is rarely visually recognised during routine fibreoptic or video endoscopy, extensive four quadrant biopsy sampling every 1–2 cm of the entire mucosal surface using jumbo biopsy forceps (Seattle protocol) has been extensively practised, validated, and is currently recommended.¹ In a recent report by the pioneers of this approach, the use of this systematic jumbo biopsy protocol every 1 cm in patients with high grade dysplasia who eventually developed cancer, 100% of cancers were detected.² However, because the technique is labour intensive and requires a therapeutic endoscope, it is used by less than 20% of US gastroenterologists.³ Recently, many strategies and innovative techniques have been developed to improve the sensitivity of dysplasia detection and to overcome the problems of sampling error. Such approaches aim at enhancing the image contrast of the mucosa, detecting biochemical changes associated with dysplasia, and increasing the image resolution. The purpose of all of these approaches has been to improve from the small degree (S) of resolution and tissue penetration to medium (M), large (L), or even extra large (XL) levels of refinement, sensitivity, and specificity not only for dysplasia but also for a wider range of end points of screening and surveillance (table 1).

For the uninitiated endoscopist, these novel techniques are briefly described here and summarised in table 2. Chromoendoscopy uses a standard video endoscope to visualise the mucosal surface after application of a dye, such as methylene blue or indigo carmine.⁴ High magnification endoscopy employs a special endoscope that has additional lenses …