Spyglass visual impression and Spybite targeted biopsies for diagnosis of biliary strictures of unknown reasons: a meta-analysis

Abstract

Objective To study the diagnostic value of Spyglass visual impression and Spybite targeted biopsies for biliary strictures of unknown reasons. Methods Several Chinese and English databases were electronically searched for studies on biliary strictures diagnosed with Spyglass visual impression and Spybite targeted biopsies compared with golden standard (pathological biopsy, autopsy and long-term clinical follow-up). The methodological quality of the included studies was assessed according to QUADAS-2 items. The software Meta-DiSc (version 1.4) was used to conduct pooling on sensitivity, specificity, positive likelihood radio, negative likelihood radio and diagnostic odds ratio (DOR). Heterogeneity test was performed and the summary receiver operating characteristic curve (SROC) was drawn for area under the curve (AUC). Results A total of 12 studies met the inclusion criteria, involving 532 patients who received Spyglass visual impression and 525 who received Spybite targeted biopsies. The combined specificity, sensitivity, positive likelihood ratio, negative likelihood ratio and DOR were 0.90 (95%CI: 0.85-0.94), 0.89 (95%CI: 0.85-0.93), 7.12 (95%CI: 4.36-11.64), 0.12 (95%CI: 0.07-0.22)and 82.40 (95%CI: 33.73-201.28)for Spyglass visual impression, and 0.98 (95%CI: 0.96-1.00), 0.66 (95%CI: 0.60-0.71), 13.29 (95%CI: 6.92-25.53), 0.37 (95%CI: 0.28-0.47)and 51.05 (95%CI: 23.58-110.53) for Spybite targeted biopsies, respectively. The AUC on the SROC of Spyglass visual impression and Spybite targeted biopsies were 0.957 4 and 0.939 8, respectively. Conclusion Spyglass visual impression is useful for detecting malignant lesion, whereas Spybite targeted biopsies is better at confirming malignant diagnosis, which indicates combination of the two methods have good diagnostic value for indeterminate biliary strictures, but their negative results are not perfect in excluding biliary cancer. Key words: Meta-analysis; Spyglass direct visualization system; Spybite tageted biopsy; Indeterminate biliary stricture