Comparison of three- and two-dimensional sonography in diagnosis of gallbladder diseases: preliminary experience.

OBJECTIVE: To compare three-dimensional sonography with two-dimensional sonography for diagnosis of gallbladder diseases. METHODS: Sixty-three patients with gallbladder diseases were examined with two- and three-dimensional sonography. The morphologic features presented on both modalities were analyzed, and the diagnostic accuracies of both modalities were evaluated and compared. RESULTS: Both two- and three-dimensional sonography facilitated correct diagnosis in all patients with gallstones. Three-dimensional sonography had no influence on the diagnosis of gallstones compared with two-dimensional sonography. Three-dimensional sonography showed the granular surfaces in 18 (81.8%) of 22 cases of polypoid lesions and the pedunculated fundus in 19 (86.4%) of 22, whereas two-dimensional sonography displayed them in 10 (45.5%) and 3 (13.6%) of 22, respectively (P < .05 and .001). Three- and two-dimensional sonography made correct differential diagnoses between non-neoplastic and neoplastic polyps in 20 (90.9%) and 12 (54.5%) of 22, respectively (P < .05). In gallbladder carcinoma, both three- and two-dimensional sonography accurately showed all the associated gallstones and intrahepatic bile duct dilatation. Two-dimensional sonography could not correctly define the locations of the lesions in 2 (28.6%) and tumor extension in 1 (14.3%) of 7 cases with pathologically proved gallbladder cancer, whereas three-dimensional sonography improved the diagnosis in these cases. CONCLUSIONS: Three-dimensional sonography adds no advantages for diagnosis of gallstones compared with two-dimensional sonography, but it is better than two-dimensional sonography for differential diagnosis of gallbladder polyps and may improve the localization and staging for gallbladder carcinoma; however, additional studies are needed for further determination.