The Diagnostic Ability of White Light Endoscopy and Magnifying Endoscopy With Optical Enhancement System

Stomach cancer is the second most common cause of cancer death. Endoscopic identification and treatment of gastric intestinal metaplasia (GIM) and early gastric cancer (EGC) is essential to improve patients' 5-year survival rates. Conventional endoscopy with white light imaging (WLI) is widely used for endoscopic evaluation of EGCs. However, conventional endoscopic visualization of EGCs has a high rate of interobserver variability and correlates poorly with the histological findings. For this reason, diagnosis has been based mostly on repeated endoscopy with multiple biopsy samples. It has been reported that optical enhancement (OE) system is useful for discriminating cancerous lesions from non-cancerous lesions. The OE system is the newly developed image-enhanced endoscopic technology, which combines high definition white light endoscopy (WLE) and optical filters that limit the spectral characteristics of the illumination light. The optical filters can achieve higher overall transmittance by connecting the peaks of the hemoglobin absorption spectrum creating a continuous wavelength spectrum. Magnifying endoscopy is useful for observing the mucosal structures and microvessels. The VS theory proposed by Yao K is widely used in Magnifying endoscopy with optical enhancement system (ME-OE). Based on technical considerations, it is conceivable that ME-OE imaging techniques might have a distinct advantage over WLE in the diagnosis of endoscopic lesions. However, few reports have objectively proved that ME-OE is superior to WLE in the detection rate and diagnostic efficiency of EGCs.