Quantitative evaluation of cerebellar perfusion in elderly patients with unilateral vertebral artery hypoplasia using pseudo-continuous arterial spin labeling

Background: To quantify cerebellar perfusion in elderly patients with unilateral vertebral artery hypoplasia (VAH) using pseudo-continuous arterial spin labeling (PCASL), and to further investigate the effect of VAH on the ipsilateral cerebellar perfusion. Methods: 273 elderly patients with unilateral VAH were included in this study. All patients underwent MRI measurement at 3T, including PCASL and T1-weighted imaging. Two neuroradiologists independently post-processed and evaluated PCASL images. The cerebral blood flow (CBF) of the bilateral inferior cerebellar hemispheres was measured. All data were divided into two groups: VAH-side group and normal-side group. The CBF of each side was the average of the data measured by the two neuroradiologists. CBF values were tested for the difference between the two groups using SPSS 26.0 software. Results: There was a good interobserver agreement in the CBF values between the two neuroradiologists (ICC=0.893, p <0.05). The CBF values of the VAH-side and normal-side groups were 39.844±9.235 and 45.174±8.342 respectively. Significantly reduced CBF values were shown in the VAH-side group compared with the normal-side group ( t = −13.351, p <0.01). Conclusions: PCASL can accurately detect cerebellar hypoperfusion in elderly patients with unilateral VAH. The cerebellums with ipsilateral VAH in elderly patients are mostly hypoperfused and vulnerable to ischemia.