ABSTRACT Background and Purpose Lenticulostriate arteries (LSAs) can be delineated by 7 Tesla (T) time‐of‐flight (TOF) magnetic resonance angiography (MRA); however, the accuracy of identification at 7 T has not yet been quantitatively assessed. This study compares the accuracy of identifying LSAs between MRA performed at 3 T and 7 T in patients with unruptured middle cerebral artery (MCA) aneurysms, using the findings of two‐dimensional (2D) intraoperative video as the reference. Methods Twenty‐nine patients underwent three‐dimensional (3D) TOF MRA acquired at both 3 and 7 T before surgery. The number of LSAs on the MRA maximum intensity projection and axial source images (N TOF ) was counted using standard 3 T (S3T), standard 7 T (S7T), and high‐resolution 7 T (HR7T) 3D TOF. The number of LSAs branching from the horizontal portion of each MCA with an aneurysm was counted on intraoperative video, and the diameter of each LSA was estimated. Results N TOF /N V was greater in HR7T 3D TOF (100%) than in S3T 3D TOF (50%) ( p < 0.05); no differences were observed between the other combinations. The TOF‐visible diameter of the LSA was smaller with HR7T 3D TOF (0.4 mm) than with S3T 3D TOF (0.6 mm) ( p < 0.05); no differences were observed between the other combinations. Conclusion HR7T 3D TOF identifies LSAs more accurately than S3T 3D TOF in patients with unruptured MCA aneurysms.
Yanagihara et al. (Wed,) studied this question.