Outcomes of Endoscopic Ultrasound-Guided Liver Biopsy Using 22-Gauge vs. 19-Gauge Needles with a Novel Hydrostatic Sampling Technique.

Background and aims: Prior data have shown specimen quality suffers when 22-gauge needles are used in place of 19G needles during endoscopic ultrasound-guided liver biopsy (EUS-LB). Emerging data suggest a novel hydrostatic sampling technique (HST) may offer improved performance over wet suction (WS). We hypothesized EUS-LB using a 22G fine-needle biopsy needle with the HST would attain similar tissue adequacy to 19G needles.

Methods: We retrospectively examined a prospectively collected database of EUS-LBs between 1/2021-9/2024. All biopsies were performed with a 22G or 19G needle using one pass with three actuations. All specimens were re-reviewed by an expert pathologist blinded to needle gauge and technique.

Results: 126 EUS-LBs (30 via 22G HST, 44 via 19G HST, and 52 via 19G WS) were performed in 120 patients. Compared to 22G HST, tissue adequacy (length ≥2cm and ≥11 complete portal tracts [CPTs]) was identical in 19G HST (93% vs. 93%, p=0.98) and lower in 19G WS (93% vs. 85%, p=0.25). Median aggregate specimen length was 5.10 cm, 5.63 cm, and 5.30 cm and CPT count was 24, 26, and 21 in 22G HST, 19G HST, and 19G WS, respectively. 22G HST had significantly less blood contamination compared to both 19G HST and 19G WS with no significant differences in specimen fragmentation.

Conclusions: When using the HST, EUS-LB with 22G needles meets adequacy standards at high rates similar to 19G needles. The HST may allow for the use of 22G needles in patients at high risk for adverse events or with challenging anatomies.