Chemical-shift MRI versus washout CT for characterizing adrenal incidentalomas

ObjectiveTo compare the accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) in characterizing adrenal masses.Materials and methodsA total of 45 adrenal masses in 38 patients underwent unenhanced CT, enhanced CT, and chemical-shift MRI. Sensitivities and accuracies using the lesion attenuation values, absolute or relative percentage washout for CT, and adrenal-to-spleen ratio or signal intensity index for MRI were calculated. Follow-up or histopathology was used as standard reference.ResultsA total of 15 lipid-rich adenomas, 6 lipid-poor adenomas, and 24 nonadenomas were obtained. The sensitivities for adenoma on MRI versus CT were 81% and 95%, respectively. The specificities were 100%.ConclusionCT is superior to MRI in characterizing adenomas.