Reference-Diagnostic Accuracy of Transesophageal Echocardiography, Helical Computed Tomography, and Magnetic Resonance Imaging for Suspected Thoracic Aortic Dissection: Systematic Review and Meta-analysis. By Shiga T et al in Arch Intern Med 2006 Jul 10;166(13):1350-6.
"Patients with suspected thoracic aortic dissection require early and accurate diagnosis. Aortography has been replaced by less invasive imaging techniques including transesophageal echocardiography (TEE), helical computed tomography (CT), and magnetic resonance imaging (MRI); however, accuracies have varied from trial to trial, and which imaging technique should be applied to which risk population remains unclear.
In their study authors found Pooled sensitivity and specificity were comparable between imaging techniques. The pooled positive likelihood ratio appeared to be higher for MRI than for TEE or helical CT. All 3 imaging techniques, ie, TEE, helical CT, and MRI, yield clinically equally reliable diagnostic values for confirming or ruling out thoracic aortic dissection."