Cerebral Perfusion Features in Takayasu Arteritis: Insights From pCASL MRI.

Objective: This study aimed to investigate the cerebral perfusion features in patients with Takayasu arteritis (TA) involving the brain blood supply arteries with pseudo-continuous arterial spin labeling magnetic resonance (pCASL) imaging.

Methods: pCASL-MRI was utilized to measure the cerebral perfusion in the whole brain and various brain regions of healthy individuals and TA patients. The differences in cerebral blood flow (CBF) and arterial transit time (ATT) were compared between TA patients and healthy controls, as well as within TA patients based on the history of cerebral infarction, disease duration, disease activity, and the extent of vascular lesions. Independent sample t-test or Mann-Whitney U test was used according to the distribution of data, and p < 0.05 was considered statistically significant.

Results: A total of 75 healthy women and 18 female TA patients with at least one supra-aortic and/or intracranial artery ≥ grade 2 were included in this study. The mean disease duration of the 18 TA patients was 7 years, with 6 patients having a history of cerebral infarction (CI). Compared to healthy individuals, TA patients had significantly lower CBF [whole brain_left CBF: 48.88 ± 8.17 mL/100 g/min vs. 57.24 ± 8.28 mL/100 g/min (p < 0.001), whole brain_right CBF: 48.68 ± 8.05 mL/100 g/min vs. 56.38 ± 8.15 mL/100 g/min (p = 0.001)], and longer ATT [whole brain_left ATT: 1.067 ± 0.201 s vs. 0.968 ± 0.139 s (p = 0.014), whole brain_right ATT: 1.037 ± 0.208 s vs. 0.935 ± 0.144 s (p = 0.015)]. Further analysis in various brain regions revealed that the CBF levels in both left and right cerebral hemispheres, cerebellar hemispheres, frontal, temporal, parietal, and occipital lobes were significantly lower in TA patients than those in healthy individuals (p < 0.05). In TA patients, both non-CI group and CI group had lower CBFs across all brain regions when compared to the healthy controls, accompanied by longer ATTs. However, no significant differences were found between the two groups in terms of CBF and ATT levels. Additionally, stratified analysis revealed TA patients with vertebral artery lesion ≥ grade 3 had significantly lower CBF levels and longer ATTs compared to those with < grade 3.

Conclusions: TA patients with moderate to severe lesions of supra-aortic and/or intracranial arteries have significant cerebral perfusion deficits. The extent of vertebral artery involvement is closely related to lower cerebral perfusion in TA patients. pCASL-MRI has a great potential for non-invasive, convenient, and dynamic evaluation of cerebral perfusion in TA patients.