Читать книгу The Esophagus - Группа авторов - Страница 207

Confocal laser endomicroscopy (CLE) utilizes a low‐power laser light‐emitting source, pinhole filter, and lens to literally focus on cellular features in the most superficial layers of tissue. The narrowly focused parallel light penetrating the tissue and reflectance from the tissues are ideally suited to examine tissue perpendicular to the objective lens; however, this can be difficult in the tangential alignment we often find ourselves in with the esophagus. This technology can be termed an “optical biopsy” due to its ability to provide special resolution comparable to histologic examinations. The earliest attempts to visualize tissue without contrast agents found poor image resolution compared to contrast‐enhanced CLE. Fluorescein 10% contrast dosing is not standardized and varies from 2.5 to 10 mL intravenously immediately before the imaging. This technology has developed through two strategies: in probe (pCLE) catheter‐based equipment from Cellvizio (Mauna Kea Technologies, Paris, France), and integrated into specialized endoscopes (eCLE) from OptiScan (Victoria, Australia; and Pentax, Tokyo, Japan). The integrated endoscope system may not be commercially viable. Reusable endoscopic probes for the esophagus and stomach provide resolution to 1 μm and have a maximum of 20 uses. Other commercially available probes are designed for colonic, biliary pulmonary, urinary epithelium, and pancreatic cysts. Probe‐based CLE education is provided with online interactive programs in BE, gastric diseases, pancreatic cysts, and inflammatory bowel disease at www.Cellvizio.net. Real‐time imaging with CLE requires a dedicated infrastructure to support the time, equipment, and expertise needed for this advanced imaging. The payoff appears to be high yield of neoplasia with CLE‐targeted biopsy (34%) compared to with high‐definition random biopsy (7%) [14]. In this prospective randomized study of 192 patients using endoscope‐based CLE, the authors suggested that up to 65% of patients referred for surveillance would not need a traditional histologic biopsy. The ASGE Technology Committee reviewed the data and recommended CLE as an emerging technology with the potential to significantly reduce the number of biopsies in BE; however, further studies are necessary to evaluate the clinical efficacy and cost‐effectiveness before utilization in both academic and community settings [15].

Figure 7.1 VLE Barrett’s esophagus case 1: 63‐year‐old with random surveillance biopsies reported indefinite for dysplasia and no focal abnormalities on high‐definition white‐light endoscopy or NBI; had VLE targeted endoscopic mucosal resection revealing high‐grade dysplasia. (A) NBI representative image; (B) VLE revealing abnormalities at 3 o’clock; (C) VLE targeted area detail; (D) laser markings at 3 o’clock.

Figure 7.2 VLE Barrett’s esophagus case 2: 70‐year‐old with random surveillance biopsies reported low‐grade dysplasia and no focal abnormalities on high‐definition white‐light endoscopy or NBI; had VLE targeted endoscopic mucosal resection revealing low‐grade dysplasia. (A) White light representative image; (B) NBI representative image; (C) VLE revealing abnormalities at 5 o’clock; (D) VLE targeted area detail; (E) laser markings at 4 o’clock.

Figure 7.3 VLE Barrett’s esophagus case 3: 60‐year‐old with random surveillance biopsies reported high‐grade dysplasia and no convincing abnormalities on high‐definition white‐light endoscopy and equivocal changes on NBI; had VLE targeted endoscopic mucosal resection revealing high‐grade dysplasia. (A) and (B) White light representative images; (C) VLE representative image revealing abnormalities at 11 o’clock; (D), (E), and (F) VLE targeted area detail; (G) NBI image with laser markings at 12 o’clock.