19 G needles provide superior tissue adequacy and histological diagnosis compared to 22 G needlesThicker Needles May Improve Tissue Quality in Liver Biopsies

BACKGROUND: Liver biopsy is the gold standard for histologic diagnosis of parenchymal liver disease. Endoscopic ultrasound-guided liver biopsy (EUS-LB) is increasingly being performed for tissue acquisition. However, the needle size to perform the procedure is still debated. We performed a systematic review and meta-analysis comparing outcomes and safety of two different needles, 19 gauge (G) and 22 G, for EUS-LB. METHODS: A comprehensive search of multiple databases was conducted to identify studies comparing 19 G and 22 G needles for liver biopsy. Studies reporting tissue adequacy, histologic diagnosis, and other relevant outcomes were included. A meta-analysis was conducted using random-effects models, and heterogeneity was assessed using standard methods. RESULTS: Our analysis of six studies revealed the superiority of 19 G needles in terms of tissue adequacy (odds ratio [OR] 7.9, 95% confidence interval [CI] 1.9-32.0,  = 0.004) and obtaining a histological diagnosis (OR 7.25, 95% CI 1.4-36.7,  = 0.02) compared to 22 G needles. Both needle sizes performed similarly in obtaining long intact core preprocessing; however, 19 G needles yielded significantly longer intact cores postprocessing. Postprocedural pain was similar between groups. CONCLUSION: Our meta-analysis supports the preferential use of 19 G needles over 22 G needles for EUS-LB, given their superior performance in tissue adequacy and histological diagnosis with no difference in postprocedural adverse events. These findings underscore the importance of appropriate needle size in optimizing EUS-LB outcomes.