Ability of a novel blue laser imaging system for the diagnosis of colorectal polyps

Background A new endoscope system with a laser light source, blue laser imaging ( BLI ), has been developed by F ujifilm that allows for narrow‐band light observation. The aim of the present study was to evaluate the utility of BLI for the diagnosis of colorectal polyps. Methods We retrospectively analyzed 314 colorectal polyps that were examined with BLI observation at K yoto P refectural U niversity of M edicine between S eptember 2011 and J anuary 2013. The surface and vascular patterns of polyps detected by published narrow‐band imaging magnification: H iroshima classification were used. Correlations were determined between the classifications and the histopathological diagnoses. Additionally, the ability of BLI without magnification to differentiate between neoplastic or non‐neoplastic polyps was analyzed. Results A total of 41 hyperplastic polyps, 168 adenomas, 80 intramucosal cancer, 11 shallowly invaded submucosal cancer, and 14 deeply invaded submucosal cancer were analyzed.Hyperplastic polyp was observed in 100% of T ype A lesions (39 lesions), adenoma was observed in 89.3% of T ype B lesions (159 lesions), intramucosal cancer and shallowly invaded submucosal cancer was observed in 69.6% of T ype C 1 (92 lesions) and in 84.6% of T ype C 2 (13 lesions), and deeply invaded submucosal cancer was observed in 81.8% of T ype C 3 lesions (11 lesions). The overall diagnostic accuracy of BLI with magnification was 84.3%. Additionally, the diagnostic accuracy of BLI without magnification for differentiating between neoplastic and non‐neoplastic polyps <10 mm in diameter was 95.2%, which was greater than that of white light (83.2%). Conclusion BLI was useful for the diagnosis of colorectal polyps.