Radionuclide angiography in suspected acute cholecystitis: further observations.

Radionuclide angiography (RNA) and cholescintigraphy were performed prospectively in 300 patients with suspected acute cholecystitis (AC). Of 79 patients with positive RNA, 63 had AC (80%). Positive RNA was seen in 23 of 26 cases with gangrenous AC (88%) while 12 of the 26 had a positive "rim" sign (46%). All 12 patients with a positive "rim" sign had positive RNA. The "rim" sign may be caused by increased perfusion. Five of 6 patients with positive RNA and "obstructive" pattern had AC (83%). Patients with negative RNA and positive cholescintigraphy had a positive predictive value of 54% (31/57), while those with positive RNA and positive cholescintigraphy had a positive predictive value of 85% (57/67). RNA showed increased perfusion to nonbiliary pathology such as liver abscesses and pyelonephritis. Positive RNA increases the predictive value of cholescintigraphy and may be useful to shorten cholescintigraphic examinations.