title: Determinants of Basal Collaterals in Moyamoya Disease: Clinical and Genetic Factors.
abstract: OBJECTIVE
  To enable the diagnosis of moyamoya disease (MMD), detection of distal internal carotid artery stenosis and hazy network of basal collaterals (BCs) are required. This study aimed at evaluating the factors that could determine the degree of BCs in patients with angiographically confirmed MMD.
  
  
  METHODS
  We analyzed 146 consecutive patients with MMD (age 26.2 ± 19.6, range 1-75). The degree of BCs (%) was measured based on conventional angiography. Factors associated with the degree of BCs, including clinico-radiological and genetic factors (p.Arg4810Lys variant), were analyzed.
  
  
  RESULTS
  The degree of BCs varied among MMD patients and significantly decreased with an increase in the age of diagnosis of MMD (coefficient -1.55; p < 0.001). Although the degree of BC development depends on the MMD stage (Suzuki stage), it is less prominent in adult-onset (>18 years) MMD compared to childhood MMD. The presence of p.Arg4810Lys variant, types of MMD (bilateral vs. unilateral) and stroke (ischemic, hemorrhagic, or asymptomatic), shrinkage (outer diameter) of intracranial vessels, external carotid collateral status, and cortical neovascularization were not associated with the degree of BCs.
  
  
  CONCLUSIONS
  Although prominent BCs are required for diagnosis of MMD, BCs are decreased with aging, suggesting that angiogenic capacity is altered in adult onset MMD compared to childhood MMD.
authors.affiliation: Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jong-Won
authors.initials: JW
authors.lastname: Chung
authors.forename: Suk Jae
authors.initials: SJ
authors.lastname: Kim
authors.forename: Oh Young
authors.initials: OY
authors.lastname: Bang
authors.forename: Kun Ha
authors.initials: KH
authors.lastname: Kim
authors.forename: Chang-Seok
authors.initials: CS
authors.lastname: Ki
authors.forename: Pyeong
authors.initials: P
authors.lastname: Jeon
authors.forename: Je Young
authors.initials: JY
authors.lastname: Yeon
authors.forename: Jong-Soo
authors.initials: JS
authors.lastname: Kim
authors.forename: Seung Chyul
authors.initials: SC
authors.lastname: Hong
authors.forename: Hyung Jin
authors.initials: HJ
authors.lastname: Shin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000473:pathology; D001921:Brain / Q000098:blood supply*; D002648:Child; D002675:Child, Preschool; D003097:Collateral Circulation; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009072:Moyamoya Disease / Q000175:diagnosis* / Q000235:genetics* / Q000473:pathology*; D009389:Neovascularization, Pathologic / Q000473:pathology; D055815:Young Adult