The interrupted rim sign in acute cholecystitis: a method to identify the gangrenous form with MRI

We present the imaging findings on MR of a patient with acute gangrenous cholecystitis that demonstrated patchy enhancement of the gallbladder mucosa on gadolinium-enhanced fat-saturated T1-weighted gradient echo images. This interrupted rim of mucosal enhancement correlated with patchy areas of necrosis and inflammation of the gallbladder mucosa on the histopathological examination.     

Diagnostic significance of the CT rim sign in cases of gangrenous cholecystitis

PurposeTo evaluate the association between the CT rim sign and gangrenous cholecystitis (GC) and increased surgical difficulty.MethodPatients who had a contrast enhanced CT of the abdomen and pelvis, followed by non-elective cholecystectomy were analyzed. The scans were reviewed for the CT rim sign by radiologists blinded to the pathologic and clinical outcomes. Demographic and clinical characteristics were compared between patients with and without GC using t-tests or Wilcoxon ranked sum test for continuous variables, and Fishers' exact test for categorical variables, when appropriate. A logistic regression model was fitted with multiple risk factors. Odds ratios as well as 95% confidence intervals were then calculated for the risk factors. A secondary analysis predicting increased surgical difficulty, defined as an operative time of greater than 2 h or increased conversion rate to open surgery, was also examined.ResultsA total of 100 patients were included; 20 of which had GC. On imaging, patients with GC were more likely to have a CT rim sign (65% vs 32.5%, OR = 3.80, 95% CI: 1.24–12.7, p = 0.011). The presence of the CT rim sign did not reach a statistically significant association with an operative time >2 h or conversion to open case (56.52% vs 33.77%, OR = 2.55, p = 0.056).ConclusionThe CT rim sign can be utilized to raise the possibility of GC, however the presence of the CT rim sign does not demonstrate an association with increased surgical difficulty.     

Delayed visualization of the gallbladder with a rim sign. An unusual finding in chronic cholecystitis

The rim sign of increased activity in the gallbladder fossa during nuclear hepatobiliary imaging has been described, with one exception, only in conjunction with a nonvisualizing gallbladder, and it strongly suggests acute complicated cholecystitis. A case is presented in which a rim sign was present despite later visualization of the gallbladder in presumed chronic cholecystitis.     

The sonographic diagnosis of acute gangrenous cholecystitis: importance of the Murphy sign

The sonographic Murphy sign is defined as the presence of maximal tenderness elicited by direct pressure of the transducer over a sonographically localized gallbladder. The reported prevalence of this sign is more than 95% in patients with acute cholecystitis. In this series of 18 patients with pathologically proved gangrenous cholecystitis, the sonographic Murphy sign was positive in only six (33%). Clinical examination showed a positive Murphy sign in eight patients (44%), diffuse abdominal pain in nine patients (50%), and no pain in one patient (6%). Other sonographic findings included pericholecystic fluid (10), thickening of the gallbladder wall (10), and a dilated gallbladder (five). Our experience suggests that the absence of the Murphy sign increases the possibility of gangrenous cholecystitis in patients with abdominal pain and sonographic findings of cholecystitis.     

Hyperdense gallbladder wall sign: an overlooked sign of acute cholecystitis on unenhanced CT examination

We reviewed the unenhanced computer tomography (CT) scans of 53 patients with surgically proven acute cholecystitis, where 27 patients presented with hyperdense gallbladder wall. To our knowledge, this sign was never reported before. Because mucosa is highly sensitive to ischemia, early mucosal necrosis and hemorrhage may result in CT-detectable high density. Similar episode may also occur in acute cholecystitis. This sign also reflects high probability for acute gangrenous cholecystitis. We suggest that patients with this sign should have urgent treatment.     

Case report. The iron rim sign.

A chronic cystic cerebral hematoma occurred in the frontal lobe and mimicked both clinically and radiographically a frontal sinus mucocele. A rim seen on multidirectional tomography and unenhanced computed tomography was presumed to be composed to calcium. However, electron microscopic analysis revealed the rim to be composed almost entirely of iron from hemosiderin breakdown products. This is the first such report of an "iron rim" that we could find in the literature.     

Biliary scintigraphy. The "hot rim" sign

A new cholescintigraphic finding, the "hot rim" sign, is reported in a case of acute cholecystitis. Local inflammation in the gallbladder fossa may be the cause of this phenomenon.     

Renal subcapsular rim sign. Radionuclide pattern

The renal cortical rim sign is a radiological term describing the thin peripheral nephrogram of 2-4 mm thick which is from the peri-renal capsular collateral circulation in an otherwise nonfunctioning kidney. Radionuclides are used frequently in the estimation of renal function. A neonate with renal vein thrombosis demonstrated a rim sign on renal scan with Technetium DTPA. The rim sign on renal scan can be differentiated from severe hydronephrosis or multicystic kidney both of which may have a peripheral thin cortex which functions late on the renal scan. The rim sign in renal vein thrombosis was best visualized during the early blood pool phase when there was a considerable amount of radioactivity in the blood pool.     

An early rim sign in neonatal adrenal hemorrhage.

Neonatal adrenal hemorrhage can usually be diagnosed on excretory urography without resorting to surgical exploration or invasive diagnostic procedures. In the typical case an avascular mass is seen between the liver and kidney. A case is presented in which a vascular rim surrounded the avascular mass, giving an appearance similar to that of an obstructed upper pole renal duplication. This early vascular rim, not as well known as the calcified rim which develops days to weeks after the acute hemorrhage, is probably created by compression and displacement of adrenal tissue by the central hemorrhage.     

Phantom gallbladder. A variant of the rim sign

Nonvisualization of the gallbladder is the primary finding in cholescintigraphy for acute cholecystitis. Recent investigators have described a useful secondary finding of increased pericholecystic hepatic activity (PCHA). A case of acute cholecystitis is presented in which the PCHA was round in configuration and appeared in the first 5 minutes of the study. This may be a source of diagnostic error if it is interpreted as visualization of the normal gallbladder. Appearance of the PCHA has not been previously described before 30 minutes. This case of early appearance raises the possibility that hyperemia may play a role as the cause in some forms of the PCHA. The phantom gallbladder was correctly identified as PCHA by observing the peak of activity of the PCHA occurring before the appearance of intrahepatic biliary radicals.