Comparison Between Non-Enhanced Magnetic Resonance Angiography (MRA) and Digital Subtraction Angiography (DSA) for the Detection of Intratumoral Aneurysms in Renal Angiomyolipoma (Renal AML).

To evaluate the diagnostic performance of non-enhanced MRA in detecting intratumoral aneurysms in renal AML, using digital subtraction angiography (DSA) as the reference standard. Fourteen female patients (mean age, 39 years; range, 21-57 years) who received prophylactic transcatheter arterial embolization (TAE) for non-hemorrhagic renal AML(s) between July 2010 and September 2018 were included in this study. All received a non-enhanced MRA scan prior to TAE. Non-enhanced MRA images were obtained using the flow-in technique with three-dimensional balanced steady-state free precession (SSFP). The MRA and DSA images were jointly evaluated by three radiologists. In this study, significant aneurysms were defined as aneurysms with a diameter of 3 mm or more within the renal AML. The MRA images assessed the number and location of significant aneurysms. The DSA images were used as the reference standard. DSA identified 30 significant aneurysms in eight kidneys; MRA identified 26, giving a sensitivity of 87%. There were no false positives, resulting in a specificity of 100%. Flow-balanced SSFP MRA is effective in detecting significant aneurysms in renal AML and could be a viable alternative for patient follow-up.