Intracranial aneurysm detection with 3T magnetic resonance angiography

Introduction: The new 3 Tesla (T) magnetic resonance (MR) scanners yield improved signalto-noise ratio and spatial resolution with superior background suppression compared to lower field strength systems. This is advantageous for MR angiograms. The purpose of our study was to compare unenhanced three-dimensional time-of-flight magnetic resonance angiography (3D TOF MRA) at 3T with catheter digital subtraction angiography (DSA) in detecting unruptured intracranial aneurysms. Materials and Methods: Out of 1375 consecutive patients who underwent unenhanced 3D TOF MRA at3T, 15 patients with unruptured intracranial aneurysinswere retrospectively identified. Nine of these 15 patients had DSA as the reference standard for comparison. Aneurysm size, location and morphologywere independently assessed on both MRA and DSA by 2 radiologists. Results: Seventeen aneurysms ranging in size from 1 mm to 24 mm were identified in 15 patients on MRA. DSA confirmed the aneurysms in 9 patients with good anatomical correlation compared with the MRA findings. Conclusions: 3D TOF MRA at 3T has good correlation with DSA and aneurysms as small as 1 mm in size can be detected. This can be a promising, non-invasive method for aneurysm surveillance.