MRI OF ACUTE CHOLECYSTITIS - COMPARISON WITH THE NORMAL GALLBLADDER AND OTHER ENTITIES

Our purpose was to prospectively compare MRI findings with histopathol ogic findings in the evaluation of suspected acute cholecystitis. Four teen patients with clinically suspected acute cholecystitis were enter ed into the study, MR sequences included T-1-weighted fat-suppression and breath-hold spoiled gradient echo (SGE) before and after intraveno us gadolinium chelate administration, Percent contrast enhancement (%C E) of the gallbladder wall and gallbladder wall thickness (WT) were me asured and liver enhancement patterns determined prospectively on MR i mages, Correlation was obtained with pathological findings at cholecyt ectomy in all patients, In a second phase of the study MR images on 10 additional subjects who underwent MR examination for reasons other th an hepatobiliary disease were analyzed to determine normal values for %CE and gallbladder wall thickness, Mean %CE was 124.0% in patients wi th acute cholecystitis (10 patients), 58.0% in patients with chronic c holecystitis (2 patients), and 73.0% in patients with gallbladder mali gnancy (2 patients), Mean gallbladder WT was 6.1 mm in acute cholecyst itis, 4.5 mm in chronic cholecystitis, and 6.0 mm in malignant disease , There was a significant difference in %CE between acute and chronic cholecystitis (p = 0.03); no other significant differences in %CE or W T were observed among the patients with gallbladder disease, Patients without biliary disease had %CE of 37.3% and WT of 2.9 mm, which were both significantly less (p < 0.001) than in patients with acute cholec ystitis. Transient enhancement of pericholecystic hepatic parenchyma o n immediate postgadolinium SGE images was seen in 7 of 10 patients wit h acute cholecystitis, and not observed in other patients, Patients wi th acute cholecystitis had increased %CE and WT on MR images that were significantly greater than normal and %CE that was significantly grea ter than in patients with chronic cholecystitis. Transient increased p ericholecystic hepatic enhancement was observed in 70% of acute cholec ystitis patients and in no other patient groups.