PERCUTANEOUS BIOPSY OF THE LIVER AND KIDNEY BY USING COAXIAL TECHNIQUE - ADEQUACY OF THE SPECIMEN OBTAINED WITH 3 DIFFERENT NEEDLES IN-VITRO

OBJECTIVE. The coaxial biopsy technique was evaluated with respect to the quality of specimens obtained from the liver and kidneys in vitro on sequential biopsies at the same site with each of three different biopsy needles. MATERIALS AND METHODS. For each of three different biopsy needles (aspiration 18-gauge Chiba, 18-gauge Sure-Cut, and 18-gauge Biopty), 30 sites (15 liver, 15 kidney) were selected for in vitro coaxial biopsy. At each site, an introducer was placed, through which three sequential biopsies were done. Blinded histopathologic analysis was used to grade the quality of specimens on a scale from 0 (no tissue) to 3 (best) for three criteria: adequacy of tissue for diagnosis, tissue fragmentation, and crush artifact. The overall score was the sum of the scores for the three individual criteria and ranged from 0 (no tissue) to 9 (best). RESULTS. Using an 18-gauge Chiba needle and coaxial technique, we found no significant reduction in specimen quality when we did multiple aspiration biopsies at the same site. However, no tissue was obtained (zero biopsy) from a large number of aspiration biopsies done with the Chiba needle, ranging from 24 of 30 for the first biopsy to 17 of 30 for the third biopsy. Specimen quality was reduced somewhat between the first and third biopsies when the 18-gauge Sure-Cut and Biopty needles were used. With the Sure-Cut needle, this reduction in quality was significant (p = .009) and was primarily related to increased tissue fragmentation and crushing. The reduction in quality with multiple biopsy attempts was less severe with the Biopty needle/gun. Although the mean score decreased from 6.6 for the first biopsy to 5.5 for the third biopsy, this reduction was not significant (p = .06). In addition, the Biopty gun, unlike the other two needles, had few zero biopsies. CONCLUSION. The use of a coaxial technique with an 18 gauge Biopty needle enables collection of a large amount of high-quality tissue for histopathologic analysis with a minimum number of failed biopsies as compared with the 18-gauge Chiba needle and the 18-gauge Sure-Cut needle.