Prospective Study of the Impact of Liver Biopsy Core Size on Specimen Adequacy and Procedural Complications.

Objective: An American Association for the Study of Liver Diseases (AASLD) consensus document stressed the importance of obtaining sufficient liver biopsy specimens to minimize sampling errors. Many centers continue to use smaller-diameter core systems to minimize perceived complication risks. The objective of this study was to assess the impact of core gauge (18- vs 16-gauge) on specimen adequacy and procedural complications.

Subjects And Methods: One hundred fifty patients referred for liver biopsy were randomized to undergo 16- or 18-gauge ultrasound (US)-guided core biopsy. Hemorrhage was qualitatively evaluated, and pain was assessed using a 10-point rating scale. The length and number of portal tracts per specimen were assessed. On the basis of the AASLD guidelines, specimen adequacy was defined as 11 or more portal tracts. Differences in pathology metrics and pain scoring were assessed using chi-square and linear regression models.

Results: No significant hemorrhage occurred in either group, and there was no difference in postbiopsy pain scores. The mean specimen length obtained with 16-gauge needles was less than that obtained with 18-gauge needles (1.7 vs 1.9 cm, p = 0.03). The mean number of portal tracts obtained with 16-gauge biopsies was greater than obtained with 18-gauge systems (14 vs 13, p = 0.03); 85% of 16-gauge biopsy specimens and 80% of 18-gauge biopsy specimens were adequate on the basis of the AASLD criteria, although this difference was not statistically significant.

Conclusion: US-guided 18- and 16-gauge core biopsies are similarly safe. A large percentage of 18- or 16-gauge specimens are inadequate when AASLD quality control adequacy thresholds are applied, and specimen adequacy is not significantly affected by biopsy gauge.