3D time-of-flight magnetic resonance angiography of lenticulostriate artery imaging at 5.0 Tesla: a hierarchic analysis method and clinical applications.

BACKGROUND

Lenticulostriate artery (LSA) arteriosclerosis is a key pathological basis for cerebrovascular diseases including stroke and cerebral small vessel disease. However, the comprehensive visualization and the meticulous quantitative analysis of the entire spectrum of LSA branches remain an ongoing clinical challenge. This study aimed to explore the efficacy of LSA branch detection using ultra-high field clinical 5.0 Tesla (T) magnetic resonance imaging (MRI) with 3D time-of-flight (TOF) magnetic resonance angiography (MRA) and to introduce a hierarchic categorization method for better LSA branching pattern analysis.

METHODS

A total of 12 participants were included and scanned using 5.0T and 3.0T TOF-MRA. First, an LSA hierarchic analysis method that categorized the LSA into three levels was proposed. Morphological parameters and signal-to-noise ratio/contrast-to-noise ratio (SNR/CNR) were calculated separately at each level. Then, the LSA imaging quality was compared between 5.0T and 3.0T TOF-MRA, utilizing the hierarchic analysis method. Next, the resolution setting in 5.0T TOF-MRA was optimized for better LSA imaging. Finally, the patient with left cerebral infarction underwent a 4-month follow-up examination using 5.0T TOF-MRA to validate the clinical utility of the 5.0T TOF-MRA and the proposed hierarchic analysis method.

RESULTS

The LSA imaging quality on 5.0T is significantly better than that of 3.0T in different levels of the LSA branches both in the numbers and lengths (P<0.05). Critically, LSA tertiary branches which were commonly delineated in the 5.0T TOF-MRA images were barely visible in the 3.0T images; furthermore, at the origin of LSA branches, 5.0T TOF-MRA showed notably superior visualization in comparison to the 3.0T (P<0.001). The clinical application studies showed the advantageous prospects of the proposed quantitative analysis method for LSA-related research at 5.0T.

CONCLUSIONS

The visibility in the branching of LSA with 5.0T TOF-MRA is superior to that of 3.0T, especially at the origination from the middle cerebral artery (MCA) and the periphery of its branches. With the implementation of the proposed hierarchic analysis method for LSA, 5.0T TOF-MRA could be a valuable instrument for identifying subtle changes in LSA associated with various cerebrovascular-related diseases.