7-Tesla magnetic resonance imaging for monitoring microstructural changes in the lenticulostriate artery-neural complex in patients with hypertension.

BACKGROUND

The lenticulostriate artery-neural complex (LNC), which includes the lenticulostriate artery (LSA) and surrounding neural structure, is a new concept proposed by neurologists and plays a pivotal role in hypertension-induced stroke. Conventional low-magnitude magnetic resonance imaging (MRI) has not been successfully used to reveal the microstructural changes of the LNC. This study aimed to evaluate the microstructural changes of the LNC in patients with prestroke hypertension using 7-Tesla (7-T) MRI and to identify the potential MRI biomarkers for monitoring hypertension-related neurological disorders.

METHODS

This prospective, cross-sectional study was conducted in Chongqing, China, from February 2023 to January 2024. Its protocol complied with the Declaration of Helsinki (revised in 2013) and was approved by the Medical Science Research Ethics Committee of Southwest Hospital, Third Military Medical University, and all participants provided written informed consent. Patients with hypertension (N=32) and age-matched healthy volunteers (N=30) were enrolled. All participants underwent 7-T MRI. The number, length, and tortuosity of the LSA were measured, as were the volumes of the basal ganglia, internal capsule, and thalamus. The relationship between the LSA features and the neural structure volumes was also analyzed through partial correlation analysis.

RESULTS

The stem, lengths of the LSA, and volume of nerve structure in LNC showed significant differences between the two groups (P<0.05). In the right hemisphere, the stem number of LSA was higher than that in the healthy group (P<0.05). Furthermore, the volumes of the globus pallidus, putamen, thalamus, caudate nucleus, and internal capsule were found to be significantly larger in healthy participants than in patients with hypertension (P<0.05). The tortuosity of the LSA was positively correlated with the internal capsule volume in the left hemisphere (r=0.460; P<0.001) and the globus pallidus (r=0.517; P<0.001). For the right hemisphere, there was a positive correlation between the stems number in the LSA and the volume of the internal capsules (r=0.340; P=0.007) and the globus pallidus (r=0.299; P=0.018). The tortuosity of the LSA was positively correlated with the volume of the internal capsule (r=0.504; P<0.001) and globus pallidus (r=0.431; P<0.001). Meanwhile, we found the number of LSA branches entering the putamen was higher in healthy individuals than in patients with hypertension (P<0.01).

CONCLUSIONS

Using 7-T MRI, we obtained ultrahigh-resolution images of the LNC and found that the microstructures of LNC were changed in the prestroke patients with hypertension. MRI monitoring of microstructural changes in LNC, including the number of LSA stems and the internal capsule and globus pallidus volume, may serve as predictive biomarkers for intracranial changes and potential complications caused by hypertension.