The Role of Cerebral Hemodynamics in Moya Moya Disease

描述（由申请人提供）：烟雾病是一种颅底大动脉闭塞性血管病变。在美国，它最常影响三、四十岁的女性，导致缺血性中风。这种疾病的自然历史尚未确定。血液动力学因素很可能在未来中风的风险中起重要作用。一些患者通过外科手术治疗，采用各种方法来改善侧支血液流向大脑。这些手术对脑血流量和随后卒中风险降低的影响尚不清楚。这项盲法、前瞻性研究将探讨脑血流动力学因素在烟雾病患者脑卒中发病机制中的作用。我们将验证这一假设，即闭塞远端大脑半球的氧气提取增加是药物治疗患者随后发生同侧缺血性卒中风险的预测因子（特定目标1）。该项目的次要目标是：(1)确定该人群中风的其他预测因素；(2)获得不同医疗方案对该人群影响的初步数据；(3)确定药物治疗患者血流动力学损伤的颞叶变化；(4)确定手术对接受手术血运重建术患者亚群血流动力学损伤的影响；(5)估计有无血流动力学障碍患者的手术并发症发生率。这些目标将通过使用正电子发射断层扫描（PET）来测量烟雾病患者的区域脑氧提取分数（OEF）来实现。临床、流行病学和血管造影危险因素的信息将在入组时获得。随后每6个月通过电话对患者进行随访，以确定随后发生的中风和预防中风的临时治疗。PET研究的结果对患者、治疗医师和监测卒中发生的研究者保密。我们将确定OEF的区域性增加是否与同侧缺血性卒中风险增加有关。我们还将进行多变量分析，以确定该样本中中风的独立预测因素。我们将对不同医疗方案的效果进行事后纵向分析。患者将每年返回进行PET随访研究。

DESCRIPTION (provided by applicant): Moyamoya disease is an obliterative vasculopathy of the large arteries at the base of the brain. In the United States, it most commonly affects women in their third and fourth decades of life, causing ischemic stroke. The natural history of this disorder is not defined. It is very likely that hemodynamic factors play an important role in the risk of future stroke. Some patients are treated surgically with a variety of procedures intended to improve collateral blood flow to the brain. The effect of these procedures on cerebral blood flow and on subsequent stroke risk reduction is unknown. This blinded, prospective study will investigate the role of cerebral hemodynamic factors in the pathogenesis of stroke in patients with moyamoya disease. We will test the hypothesis that increased oxygen extraction in the cerebral hemisphere distal to the occlusion is a predictor of the subsequent risk of ipsilateral ischemic stroke in medically treated patients (Specific Aim 1). The secondary objectives of this project are (1) to determine other predictive factors for stroke in this population; (2) to obtain preliminary data on the effects of different medical treatment regimens in this population; (3) to determine the temporal changes in hemodynamic impairment in medically treated patients; (4) to determine the effects of surgery on hemodynamic impairment in the subset of patients that undergo surgical revascularization; and (5) to obtain estimates of surgical complication rates for patients with and without hemodynamic impairment. These objectives will be accomplished by the use of positron emission tomography (PET) to measure regional cerebral oxygen extraction fraction (OEF) in patients with moyamoya disease. Information on clinical, epidemiologic and angiographic risk factors will be obtained on enrollment. Patients are subsequently followed every six months by telephone to determine the subsequent occurrence of stroke and the interim treatment for stroke prevention. Results of the PET study are kept confidential from the patient, treating physician and investigator monitoring the occurrence of stroke. We will determine if a regional increase in OEF is associated with an increased risk of ipsilateral ischemic stroke. We will also do a multivariate analysis to determine the independent predictors of stroke in this sample. We will perform a post-hoc longitudinal analysis of the effect of different medical treatment regimens. Patients will return annually for follow up PET studies.