title: Clinical Characteristics and Natural History of Quasi-Moyamoya Disease.
abstract: BACKGROUND
  Quasi-moyamoya disease (quasi-MMD) is a rare cerebrovascular disease and its clinical features and natural history remain unclear. The aim of the study is to describe the clinical characteristics and the natural histories of this disease, with analysis of the risk factors for future cerebrovascular events.
  
  
  METHODS
  We identified 64 patients with quasi-MMD from 693 moyamoya vasculopathy patients referred to our hospital between 2011 and 2015. Demographic data, associated disorders, clinical manifestation, angiographic findings, natural history, and risk factors for cerebrovascular events were analyzed.
  
  
  RESULTS
  Patients included in the study had a mean age of 31.5 years. A unimodal age distribution was noted. Atherosclerosis was the most frequently associated disorder. Forty-five (70.3%) patients had ischemic events as their initial clinical manifestation and 14 (21.9%) patients presented as hemorrhagic stroke. The majority of patients presented with Suzuki grades 3 and 4 (20.3% and 42.2%). The annual risk of cerebrovascular events was 19.4% per patient-year. Prior hemorrhage (HR 2.77, 95% CI 1.20-6.41) and ischemic stroke (HR 2.77, 95% CI 1.26-6.07) were 2 risk factors for future events.
  
  
  CONCLUSIONS
  Several clinical characteristic differences were observed in our mainland China cohort compared with the Japanese and European cohorts. The annual risk of cerebrovascular events was relatively high in quasi-MMD patients. Patients with prior hemorrhage and ischemic stroke were inclined to have future cerebrovascular events. Close follow-up is needed for these patients.
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China.
authors.forename: Zhiqin
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Deng
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing, China.
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China.
authors.forename: Zhongli
authors.initials: Z
authors.lastname: Jiang
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing, China. Electronic address: zhaojz205@163.com.
authors.forename: Jizong
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000453:epidemiology; D002533:Cerebral Angiography; D002681:China / Q000453:epidemiology; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D002537:Intracranial Arteriosclerosis / Q000000981:diagnostic imaging / Q000453:epidemiology; D020300:Intracranial Hemorrhages / Q000000981:diagnostic imaging / Q000453:epidemiology; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009072:Moyamoya Disease / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000000981:diagnostic imaging / Q000453:epidemiology; D013997:Time Factors; D055815:Young Adult
keywords: Quasi-moyamoya disease; clinical characteristics; moyamoya disease; natural history