この患者初診来院時は割と症状が軽かったのだ。確かに胆石と胆嚢炎を示唆してはいたが、理学的にはそれほどの所見ではなかった。 ただCTは異様だった。これはなんなんだ、という所見であった。次の写真はネットで探し出した「壊疽性(気腫性)胆嚢炎」のCT像である。
その次に引用したのはAJRの総説である。結論に書いてあるとおり、胆嚢壁や内腔のガス像が一番特徴的なCT所見なのだ。壁のガス像は極めて特徴的で、一度見たら忘れられない所見ではある。
Featured Articles
Affiliation: 1
All authors: Department of Abdominal Radiology, New York University
Medical Center, Tisch Hospital, Rm. HW202, 560 First Ave., New York, NY
10016.
Citation: American Journal of Roentgenology. 2002;178:275-281
ABSTRACT :
MATERIALS AND METHODS.
Four observers retrospectively reviewed CT scans in 75 patients (23
with acute gangrenous cholecystitis, 25 with acute nongangrenous
cholecystitis, and 27 without cholecystitis). The following findings
were evaluated: distention, mural thickening, wall enhancement,
irregular wall, wall striation, intraluminal membranes, pericholecystic
inflammation, gallstones, pericholecystic fluid, enhancement of liver
parenchyma, pericholecystic abscess, and gas in the wall or lumen.
Sensitivity and specificity of CT for gangrenous cholecystitis and for
each finding were calculated. Two reviewers in consensus measured
gallbladder dimension and wall thickness. Logistic regression models
were used to predict gangrenous versus nongangrenous cholecystitis.
RESULTS. Sensitivity, specificity, and accuracy of CT for acute cholecystitis were 91.7%, 99.1%, and 94.3%, respectively, and for acute gangrenous cholecystitis were 29.3%, 96.0%, and 64.1%, respectively. Findings with the highest specificity for gangrenous cholecystitis were gas in the wall or lumen (100%), intraluminal membranes (99.5%), irregular or absent wall (97.6%), and abscess (96.6%). The difference between the mean gallbladder wall thickness and the short-axis dimension for the two groups with cholecystitis was statistically significant. In three patients with gangrenous cholecystitis, no mural enhancement was seen. Pericholecystic fluid also achieved statistical significance for the diagnosis of gangrene. Multivariate logistic regression analysis showed that the overall accuracy of CT for gangrenous cholecystitis was 86.7%.
OBJECTIVE. The purpose of this study was to determine the CT findings in acute gangrenous cholecystitis.
RESULTS. Sensitivity, specificity, and accuracy of CT for acute cholecystitis were 91.7%, 99.1%, and 94.3%, respectively, and for acute gangrenous cholecystitis were 29.3%, 96.0%, and 64.1%, respectively. Findings with the highest specificity for gangrenous cholecystitis were gas in the wall or lumen (100%), intraluminal membranes (99.5%), irregular or absent wall (97.6%), and abscess (96.6%). The difference between the mean gallbladder wall thickness and the short-axis dimension for the two groups with cholecystitis was statistically significant. In three patients with gangrenous cholecystitis, no mural enhancement was seen. Pericholecystic fluid also achieved statistical significance for the diagnosis of gangrene. Multivariate logistic regression analysis showed that the overall accuracy of CT for gangrenous cholecystitis was 86.7%.
CONCLUSION. CT findings most specific
for acute gangrenous cholecystitis are gas in the wall or lumen,
intraluminal membranes, irregular wall, and pericholecystic abscess.
Gangrenous cholecystitis is associated with a lack of mural
enhancement, pericholecystic fluid, and a greater degree of gallbladder
distention and wall thickening.
