Combination of Magnetic Resonance Cholangiopancreatography and Computed Tomography for Preoperative Diagnosis of the Mirizzi Syndrome

OBJECTIVE: To determine the diagnostic accuracy of combined magnetic resonance cholangiopancreatography (MRCP) and computed tomography (CT) for preoperative diagnosis of Mirizzi syndrome. MATERIALS AND METHODS: Fifty-two patients with surgically proven Mirizzi syndrome (n = 13) and cholecystitis without evidence for Mirizzi syndrome (n = 39) underwent both MRCP using single-shot turbo spin echo and 3-dimensional turbo spin echo sequences and CT. Two blinded observers independently and retrospectively reviewed the combination of MRCP and CT images and CT images alone. Diagnostic accuracy for a combined protocol and CT was evaluated. RESULTS: The overall sensitivity, specificity, positive and negative predictive values, and accuracy of the combination of MRCP and CT were 96.0%, 93.5%, 83.5%, 98.5%, and 94.0%, respectively. Corresponding values of CT were 42.0%, 98.5%, 93.0%, 83.5%, and 85.0%, respectively. The sensitivity, negative predictive value, and accuracy of combined protocol were significantly higher than those of CT alone (P = 0.000, 0.001, and 0.042, respectively). Interobserver agreement was better for combined images (kappa = 0.906) than for CT images alone (kappa = 0.812). CONCLUSIONS: A combination of MRCP and CT is useful for preoperative diagnosis of Mirizzi syndrome.