Comparison of 3D TOF-MRA and 3D CE-MRA at 3 T for imaging of intracranial aneurysms

Purpose: To compare 3 T elliptical-centric CE MRA with 3 T TOF MRA for the detection and characterizationof unruptured intracranial aneurysms (UIAs), by using digital subtracted angiography (DSA) as reference.Materials and methods: Twenty-nine patients (12 male, 17 female; mean age: 62 years) with 41 aneurysms(34 saccular, 7 fusiform; mean diameter: 8.85 mm [range 2.0\u201326.4 mm]) were evaluated with MRA at3 T each underwent 3D TOF-MRA examination without contrast and then a 3D contrast-enhanced (CE-MRA) examination with 0.1 mmol/kg bodyweight gadobenate dimeglumine and k-space elliptic mapping(Contrast ENhanced Timing Robust Angiography [CENTRA]). Both TOF and CE-MRA images were used toevaluate morphologic features that impact the risk of rupture and the selection of a treatment. Almosthalf (20/41) of UIAs were located in the internal carotid artery, 7 in the anterior communicating artery,9 in the middle cerebral artery and 4 in the vertebro-basilar arterial system.All patients also underwent DSA before or after the MR examination.Results: The CE-MRA results were in all cases consistent with the DSA dataset. No differences werenoted between 3D TOF-MRA and CE-MRA concerning the detection and location of the 41 aneurysmsor visualization of the parental artery. Differences were apparent concerning the visualization of mor-phologic features, especially for large aneurysms (>13 mm). An irregular sac shape was demonstratedfor 21 aneurysms on CE-MRA but only 13/21 aneurysms on 3D TOF-MRA. Likewise, CE-MRA permittedvisualization of an aneurismal neck and calculation of the sac/neck ratio for all 34 aneurysms with aneck demonstrated at DSA. Conversely, a neck was visible for only 24/34 aneurysms at 3D TOF-MRA. 3DCE-MRA detected 15 aneurysms with branches originating from the sac and/or neck, whereas brancheswere recognized in only 12/15 aneurysms at 3D TOF-MRA.Conclusion: For evaluation of intracranial aneurysms at 3 T, 3D CE-MRA is superior to 3D TOF-MRA forassessment of sac shape, detection of aneurysmal neck, and visualization of branches originating fromthe sac or neck itself, if the size of the aneurysm is greater than 13 mm. 3 T 3D CE-MRA is as accurate andeffective as DSA for the evaluation of UIAs

Intracranial Aneurysms: Clinical Value of 3D Digital Subtraction Angiography in the Therapeutic Decision and Endovascular Treatment

Article dans revue scientifique avec comité de lecture.PURPOSE: To evaluate three-dimensional (3D) digital subtraction angiography (DSA) as a supplement to two-dimensional (2D) DSA in the endovascular treatment (EVT) of intracranial aneurysms. MATERIALS AND METHODS: In 22 ruptured aneurysms, neck visualization, aneurysm shape, and EVT feasibility were analyzed at 2D DSA (anteroposterior, lateral, rotational views) and at maximum intensity projection (MIP) and surface shaded display (SSD) 3D DSA. The possibility of obtaining a working view for EVT at 3D DSA and the relevance of measurements in choosing the first coil also were assessed. RESULTS: Two-dimensional DSA images clearly depicted the aneurysm neck in four of 22 aneurysms; MIP images, in 10; and SSD images, in 21, but SSD led to overestimation of the neck size in one aneurysm. Aneurysm shape was precisely demonstrated in five of 22 aneurysms, EVT seemed to be nonfeasible at 2D DSA; however, SSD demonstrated feasibility and EVT was successfully performed. In one aneurysm, only SSD demonstrated the extension of the neck to a parent vessel, which was proved at surgery. Working views for EVT were deduced from 3D DSA findings in 20 of 21 aneurysms. The choice of the first coil was correct in 19 of 21 aneurysms. CONCLUSION: Three-dimensional DSA is valuable for evaluating the potential for EVT, finding a working view, and performing accurate measurements