Randomized study of colonoscopic biopsy forceps: Influence of forceps characteristics on tissue specimens

Background: A variety of biopsy forceps, both disposable and reusable varieties, are commercially available. Little is known whether forceps characteristics such as disposability, size, shape or presence of a needle have any influence on the adequacy of the tissue specimens. Objectives To analyze prospectively in a randomized, pathologist blinded study the performance of different biopsy forceps, both disposable and reusable. Methodology Six biopsy forceps were tested: Bard disposable forceps (cup size 3.1 mm), oval-shaped, with and without a needle, and alligator-shaped, with and without a needle, Microvasive disposable alligator-shaped forceps without a needle (cup size 3.3 mm) and an Olympus reusable oval shaped forceps with a needle (cup size 3.7 mm). Two biopsy specimens were obtained with each forceps: 12 specimens per patient. All biopsies were obtained by 3 endoscopists. Biopsies were examined in a blinded fashion for: weight (mg), dimensions (mm³), depth, crush artefact, shearing effect, and adequacy of specimens for histological information (0 = inadequate, 1 = suboptimal, 2 = adequate). Results: 25 patients were studied. Specimens from reusable forceps and disposable alligator cup without needle were inferior in weight (p<0.001), size (p=0.004) and depth (p <0.001) compared to disposable forceps. Bard disposable forceps provided specimens that were deeper and larger (p<0.01) but had more crush effect than other forceps. However, when the tissue specimens were analyzed for adequacy of histological information, the only factor which influenced the results was the cup shape; oval cup forceps were significantly better than alligator cup forceps (p=0.01). Conclusion: The present study shows that oval forceps provided the best results.