The Role of Cerebral Hemodynamics in Moya Moya Disease

描述(申请人提供)：烟雾病是一种位于大脑底部的大动脉闭塞性血管病变。在美国，它最常见的影响是三四十岁的女性，导致缺血性中风。这种疾病的自然病史还没有定义。很可能血液动力学因素在未来卒中的风险中起着重要作用。一些患者接受手术治疗，采用各种旨在改善脑部侧支循环血流量的程序。这些程序对脑血流和随后的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卒中发病机制中的作用。我们将检验这一假设，即闭塞远端大脑半球氧摄取量增加是药物治疗患者随后同侧缺血性中风风险的预测因素(特定目标1)。该项目的次要目标是(1)确定这一人群中中风的其他预测因素；(2)获得关于不同医疗方案在这一人群中效果的初步数据；(3)确定接受药物治疗的患者血液动力学损害的时间变化；(4)确定手术对接受外科血管重建术的患者的血液动力学损害的影响；以及(5)获得有和没有血液动力学损害的患者的手术并发症发生率的估计。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局部脑氧提取分数(OEF)来实现。有关临床、流行病学和血管造影危险因素的信息将在注册时获得。随后，每六个月通过电话对患者进行随访，以确定随后发生中风的情况和中风预防的临时治疗。PET研究的结果对患者、治疗医生和监测中风发生的研究人员保密。我们将确定OEF的区域性增加是否与同侧缺血性卒中的风险增加相关。我们还将在此样本中进行多变量分析，以确定中风的独立预测因素。我们将对不同治疗方案的效果进行事后纵向分析。患者每年都会回来进行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.