Enhanced mucosal imaging

Abstract

The continued application of innovative imaging systems to endoscopic procedures has vastly improved the detection of indiscriminant tissue anomalies. This article describes the fundamental principles of these technologies and reviews the advances of each over the past 18 months, considering their utility in the diagnosis and surveillance of various gastrointestinal diseases. Through a combination of novel optics, processors and filters, real-time high-resolution contrast endoscopy provides increased visual data without greater procedure duration or difficulty. Optical contrast techniques incorporated into endoscopes, such as narrow band imaging (Olympus), i-Scan (Pentax), and Fujinon Intelligent Chromo Endoscopy, have become standard of care for many endoscopists. These technologies, as well as autofluorescence imaging, potentially improve detection of mucosal abnormalities, serving as 'red flag' tools for the evaluation of wide areas of mucosa. In addition, a number of promising devices allow virtual histology and in-vivo diagnosis, thereby directing biopsies and potentially guiding concurrent interventions. One such technology, confocal laser endomicroscopy, continues to establish its role in clinical practice. Because of inherent shortcomings affecting each modality's sensitivity and specificity, the coupling of various devices, as with endoscopic trimodal imaging, has shown great promise; however, most are not widely available and not definitively proven to be superior to more established techniques. Emerging technologies, including in-vivo molecular tagging, provide a powerful means of detecting disease without reliance on morphologic diagnostic criteria. Endoscopy continues to evolve from a field that previously allowed only macroscopic imaging dependent on subsequent pathology to one that allows real-time in-vivo diagnosis. Although the promise of enhanced endoscopic technologies seems limitless, practical and technological considerations slow their adoption into the standard of care.