Comparison of three dimensional time-of-flight MR angiography at 3.0 T MR and DSA in the detection of intracranial aneurysms

Objective To investigate the diagnostic accuracy of contrast-free three dimensional time-of-flight (3D-TOF-MRA) with VR at 3.0 T in the detection of intracranial aneurysms in a large cohort of patients prospectively. Methods Four hundred and eleven patients with suspected aneurysms and other cerebral vascular diseases received contrast-free 3D-TOF-MRA examinations at 3.0 T MRA 2 weeks prior to DSA examination.2D-DSA and VR-DSA were regarded as the gold standard.Six patients were excluded because of motion artifacts,and 36 patients were excluded due to lack of VR-DSA data.Accuracy,sensitivity an specificity in detecting intracranial aneurysms were determined by patient-,aneurysm-,and aneurysm size-based ( 5—10 mm,>10 mm) evaluations. Results In 369 enrolled patients,VR-DSA revealed 306 aneurysms in 246 patients (66.7%) and no aneurysm in 123 patients; VR 3D-TOF-MRA revealed 311 aneurysms in 249 patients and no aneurysm in 120 patients.The patient-based evaluation of VR 3D-TOF-MRA at 3.0T yielded accuracy of 97.6% (360/369),sensitivity of 99.2% (242/244),and specificity of 94.4% (118/125) in the detection of intracranial aneurysms.The aneurysm-based evaluation yielded accuracy of 98.3% (524/533),sensitivity of 99.3% (304/306),and specificity of 96.1% (220/229).The evaluation based on aneurysm sizes (<3 mm) yielded accuracy of 96.4% (214/222),sensitivity of 98.2% (112/114),and specificity of 94.4% (102/108). Conclusion VR 3D-TOF-MRA at 3.0 T MR can detect intracranial aneurysms accurately and may replace DSA as a contrast-free,noninvasive and nonradiation-based modality for the diagnosis and screening of intracranial aneurysms. Key words: Intracranial aneurysm; Magnetic resonance imaging; Angiography,digital subtraction; Comparative study