Lower Cerebral Blood Flow Following Surgical Treatment of Acute Type A Dissection: An Arterial Spin Labelling Study

Postoperative permanent neurological dysfunction remains a challenging complication in type A acute aortic dissection (TAAAD). Researches evaluating cerebral perfusion and altered blood flow in postoperative patients with TAAAD using non-invasive imaging techniques, such as arterial spin labelling are scarce. This study aims to assess cerebral blood flow (CBF) in postoperative patients with TAAAD, using arterial spin labeling (ASL). This study enrolled 22 postoperative patients and 25 healthy control subjects (HC), they all underwent a three-dimensional pseudo-continuous ASL MRI scanning. Voxel-based comparison of normalized CBF was conducted. The relationship between CBF variation and clinical scale assessment was further analysed. Compared with HC subjects, postoperative patients with TAAAD exhibited lower CBF levels in the right middle frontal gyrus, the right orbit of frontal gyrus, the bilateral fusiform gyrus, the right middle temporal gyrus, the bilateral inferior temporal gyrus, the bilateral lateral occipital cortex and the bilateral cerebellum (t > 3.0 and p < 0.05, FDR corrected at cluster level). These variations were also significantly correlated with multiple clinical rating scales about cognition and emotion. Postoperative patients with TAAAD exhibit abnormalities in several brain regions. The affected areas involve important component of neuro-networks, including psychological cognitive activity, attention and emotion regulation and high-level visual function.