Volumetric Laser Endomicroscopy (VLE): An OFDI Case Study of Barrettʼs Esophagus with Dysplasia

Abstract

Figure: No Caption available.Purpose: Optimal diagnosis and surveillance of patients with Barrett's esophagus (BE) is complex, given that few patients undergoing resection of esophageal adenocarcinoma have a prior diagnosis of Barrett's esophagus (BE) and, among those who have been screened and diagnosed with BE, >90% never develop adenocarcinoma. Surveillance of patients with BE is further complicated by variability in the distribution of dysplasia and cancer within the esophagus. Random sampling of esophageal biopsies can result in missed regions of interest with pathology. Thus, a significant need exists for more accurate methods of identifying areas of dysplasia in the endoscopic screening and surveillance of BE. Volumetric laser endomicroscopy uses the principles of optical coherence tomography to generate high-resolution, cross-sectional, and longitudinal images of tissue microstructures simultaneously in real time. Methods: The console generates the near infrared light and transmits the light into the VLE catheter. The console includes the swept light source, optical receiver and interferometer, data acquisition computer and control electronics, and user interface and display. The catheter is a long catheter (2.5 m) plugs into the console and has a polymer, noncompliant balloon with soft tip. Results: In this case, a 64-year-old man with long standing acid reflux and a family history esophageal carcinoma had undergone endoscopy documenting long segment BE with areas suspicious for HGD and/or carcinoma. At our institution, he underwent video endoscopy with VLE imaging documenting abnormal crypt formation and surface maturation consistent with BE HGD and focal mass treated with endoscopic resection. Conclusion: Optical coherence tomography (OCT) is an imaging modality that has the ability to improve the current paradigm for endoscopic screening and surveillance. The benefit of OCT over ultrasound is that it is capable of generating cross-sectional images of tissues with an axial-resolution of up to 10 microns, which is comparable to low-power microscopy. Original OCT systems or time-domain OCT were limited to discrete locations or ‘point' sampling due to slow acquisition rates. However, with the development of second-generation OCT, termed optical frequency domain Imaging (OFDI) now called VLE, it is now possible to perform high-speed acquisition of large luminal surfaces in three-dimensions. Due to its high-resolution and high-acquisition rates, utilizing this technique for screening and surveillance of Barrett's esophagus may provide a means to evaluate pathologic states of the esophageal lumen in real-time. Disclosure - Leslie Blackshear, E Aranda-Michel, Mayo Clinic Florida: None MB Wallace, HC Wolfsen, Mayo Clinic Florida and G Tearney Massachusetts General Hospital: Grant/Research Support. This research was supported by an industry grant from Nine Point Medical, Cambridge MA.