Oral cholecystography vs gallbladder sonography: a prospective, blinded reappraisal

In a prospective, blinded study of 205 patients, oral cholecystography (OCG) and sonography were compared in terms of how well each screened patients for gallbladder diseases. Among 23 patients who had pathologic confirmation of the diagnosis at cholecystectomy, OCG correctly diagnosed 20 cases (87%) while sonography diagnosed 18 (78%). Among 54 patients with an abnormal OCG and/or sonogram, OCG detected 47 (87%) while sonography detected 44 (81%). These small differences in detection rates were not statistically significant. On the basis of these results, we cannot conclude that either sonography or OCG has a diagnostic advantage in screening patients for gallbladder disease. The large numbers of false-negative examinations found on both sonography and OCG suggest that in a patient with persistent symptoms, the alternative study should be performed if the first examination is negative.