Ileocolic vascular curvature: a new CT finding of cecal volvulus.

PURPOSE: To evaluate the diagnostic performance of a proposed new CT observation in cecal volvulus, marked hook-like curvature of ileocolic vessels termed "ileocolic vascular curvature."

METHODS: Contrast-enhanced CT scans of 14 patients with diagnoses of cecal volvulus on original CT reports were compared with scans of 40 control patients with dilated cecum but no cecal volvulus on original CT reports, accrued consecutively from January, 2006 through July, 2017. Two independent blinded readers retrospectively evaluated scans for cecal dilatation, ileocolic vascular curvature and seven previously reported CT features of cecal volvulus. Statistical methods included the exact binomial distribution to define 95% confidence intervals (95% CIs), logistic regression, receiver operating characteristic analysis, and the exact McNemar test. Pathology reports and clinical records served as reference standards.

RESULTS: All patients had abdominal pain and cecal distension. All 14 patients with CT diagnoses of cecal volvulus, and no control patients, had cecal volvulus by reference standards. Ileocolic vascular curvature and ectopic cecal location were the only features independently and significantly associated with cecal volvulus in multivariable regression (odds ratio 178, p = 0.014, and 63, p = 0.013, respectively) and also the only features with both sensitivity (12/14 [85.7%, 95% CI 57.2-98.2%] and 13/14 [92.9%, 95% CI 66.1-99.8%], respectively) and specificity (40/40 [100.0%, 95% CI 91.2-100.0%] and 38/40 [95.0%, 95% CI 83.1-99.4%], respectively) that differed significantly from 50.0%.

CONCLUSIONS: Ileocolic vascular curvature was independently and significantly associated with cecal volvulus and exhibited both substantial sensitivity and substantial specificity for cecal volvulus, and thus is potentially a valuable new CT finding of cecal volvulus.