烟雾病搭桥术后暂时性神经功能障碍的分析

摘要

Objective To investigate the mechanism of transient neurological dificit (TND) after superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis in moyamoya disease (MMD).Methods The clinical data of 49 surgery-treated hemispheres of MMD were analyzed retrospectively.The STA-MCA anastomosis with encephalo-duro-arterio-synangiosis (EDMS) was used for cerebral revascularization.Intraoperative indocyanine green (ICG) angiogram was used to demonstrate bypass patency and hemodynamics on the cortex.99mTc-ECD SPECT and territorial-Arterial Spin Labeling (t-ASL) MR scan were used for hemodynamic study.Results TND was observed from 2nd to 7th day after operation and sustained for 7.4 days in average,with an incidence of 34.7％ (17/49),manifested as aphasia,motor and sensory disturbance and epilepsy.All symptoms were relieved without neurological deficit at discharge after proper treatment.Perioperative SPECT study revealed 2 different types of changing pattern in cerebral hemodynamic:increased peffusion (7 hemispheres,characterized by hyperperfusion around the anastomosis site),and unbalanced perfusion (10 hemispheres,characterized by slightly increased or stable perfusion around the anastomosis site with adjacent hypoperfusion).The t-ASL study revealed blood-flow redistribution between bypass flow and initial flow,inducing a phenomenon of "watershed shift",and the location of new watershed was in accordance with hypoperfusion on SPECT.It's conceivable that flow disturbance in the new watershed may cause cerebral ischemia.Conclusions TND after STA-MCA anastomosis in MMD may be caused by hyperperfusion or cerebral ischemia induced by watershed shift.Perioperative hemodynamio analysis is of paramount significance in differential diagnosis and treatment.%目的 探索颞浅动脉-大脑中动脉搭桥治疗烟雾病术后暂时性神经功能障碍(transient neurological dificit,TND)的发病机制.方法 回顾性分析49侧烟雾病半球的临床资料,均进行颞浅动脉-大脑中动脉搭桥联合脑-硬膜-肌肉血管融合术.术中行吲哚菁绿造影以描述桥动脉通畅性及皮质表面血流动力学特征,采用99mTc-ECD SPECT和磁共振区域动脉自选标记扫描(t-ASL)进行围手术期脑血流动力学观察.结果 术后2～7 d出现TND、平均持续7.4 d,发生率为34.7％ (17/49),主要表现为失语、运动、感觉障碍及癫(癎)等,经相应治疗后均恢复良好,无后遗神经功能障碍.术后早期SPECT发现两种不同的血流动力学变化规律:过度灌注(7侧,表现为吻合口周围过度灌注)与灌注失衡(10侧,表现为吻合口周围等或稍高灌注伴邻近部位低灌注).t-ASL研究提示:桥动脉血流与固有血流之间的血流重分配可导致“分水岭推移”,新的分水岭区与SPECT所示低灌注区吻合,该处血流异常即为脑缺血的原因.结论 颞浅动脉-大脑中动脉搭桥治疗烟雾病,术后TND原因包括过度灌注和“分水岭推移”所致的脑缺血,围手术期血流动力学评估对二者鉴别与治疗至关重要.