Supplementary Material for: White and grey matter perfusion in children with moyamoya angiopathy after revascularization surgery

Introduction: Surgical revascularization is very effective in patients with moyamoya angiopathy (MMA) and leads to improvements in cortical perfusion parameters. However, changes in white matter hemodynamics are still underestimated. To date, only a few studies have examined brain perfusion changes within deep white matter after bypass surgery in patients with MMA. Methods: Ten children with moyamoya angiopathy were evaluated using the CT perfusion technique before and after revascularization surgery. Brain perfusion parameters within grey and white matter were compared before and after surgery. The correlations between the perfusion parameters before surgery and the Suzuki stage, as well as between the perfusion parameters and the cognitive scores, were also evaluated. Results: Brain perfusion parameters improved significantly in both grey matter (predominantly due to cerebral blood flow within the anterior circulation, p < 0.01) and white matter (predominantly due to cerebral blood volume within the semiovale centrum, p < 0.001). We revealed that the pattern of improvement in perfusion in white matter differed from the pattern of improvement in perfusion in grey matter. Significant correlations were revealed between the Suzuki stage before surgery and the perfusion parameters within the posterior cerebral artery circulation (adjusted p < 0.05) were revealed. There were also significant correlations between cognitive scores and brain perfusion parameters in grey matter and white matter (adjusted p < 0.05). Conclusions: The perfusion parameters of grey matter and white matter in the brain improve differently after bypass surgery in patients with MMA. Different hemodynamics within these compartments could explain this.

引言：外科血管重建术对烟雾病血管病（moyamoya angiopathy, MMA）患者疗效显著，可改善皮质灌注参数，但目前白质血流动力学的变化仍未得到足够重视。迄今为止，仅有少数研究探讨了烟雾病血管病患者搭桥手术后深部脑白质内的脑灌注变化。
方法：本研究纳入10例烟雾病血管病患儿，在血管重建手术前后采用CT灌注（CT perfusion）技术进行评估，对比手术前后脑灰质与白质内的灌注参数，并分析术前灌注参数与铃木分期（Suzuki stage）的相关性，以及灌注参数与认知评分的相关性。
结果：灰质（主要因前循环脑血流量（cerebral blood flow, CBF）提升，p<0.01）与白质（主要因半卵圆中心脑血容量（cerebral blood volume, CBV）提升，p<0.001）的灌注参数均得到显著改善。本研究发现，白质灌注的改善模式与灰质灌注改善模式存在显著差异。术前铃木分期与大脑后动脉循环内的灌注参数存在显著相关性（校正后p<0.05）；认知评分与脑灰质、白质灌注参数同样存在显著相关性（校正后p<0.05）。
结论：烟雾病血管病患者接受搭桥手术后，脑灰质与白质的灌注参数改善模式存在差异，这一现象可由二者不同的血流动力学特征予以解释。