Pilot study of probe-based confocal laser endomicroscopy during colonoscopic surveillance of patients with longstanding ulcerative colitis.

BACKGROUND AND AIMS: Surveillance of patients with ulcerative colitis consists of taking targeted and random biopsies, which is time-consuming and of doubtful efficiency. The use of probe-based confocal laser endomicroscopy (pCLE) may increase efficiency. This prospective pilot study aimed to evaluate the feasibility and diagnostic accuracy of pCLE in ulcerative colitis surveillance.
METHODS: In 22 patients with ulcerative colitis, 48 visible lesions and 87 random areas were initially evaluated by real-time narrow-band imaging (NBI) and high-definition endoscopy (HDE). Before taking biopsies, fluorescein-enhanced pCLE was performed. All pCLE videos were scored afterwards by two endoscopists who were blinded to histology and endoscopy. Outcome measures were: (1) the feasibility of pCLE, expressed as pCLE imaging time required, percentage of imaging time with clear pCLE histology, and pCLE video quality as rated by two endoscopists; and (2) the diagnostic accuracy of pCLE.
RESULTS: The median pCLE imaging time required was 98 seconds for lesions vs. 66 seconds for random areas ( P = 0.002). The median percentages of imaging time with clear pCLE histology were 61 % vs. 81 % respectively ( P < 0.001). The pCLE video quality was rated as good/excellent in 69 %. Feasibility was significantly poorer for sessile and pedunculated mobile lesions. The sensitivity, specificity, and accuracy of blinded pCLE were 65 %, 82 %, and 81 %, whereas these figures were 100 %, 89 %, and 92 % for real-time endoscopic diagnosis with NBI and HDE.
CONCLUSION: This study demonstrates that pCLE for ulcerative colitis surveillance is feasible with reasonable diagnostic accuracy. Future research should show whether increased experience with pCLE improves its ease of use and whether real-time pCLE diagnosis is associated with greater diagnostic accuracy. © Georg Thieme Verlag KG Stuttgart · New York.