title: Angle between the common and internal carotid arteries detected by ultrasound is related to intima-media thickness among those with atherosclerotic disease.
abstract: OBJECTIVE
  Although carotid artery structural variations have been detected by ultrasound, their clinical significance is not fully understood. The objective of this study was to determine whether the angle between the common carotid artery (CCA) and the internal carotid artery (ICA), designated angle α, an ultrasound-detectable carotid artery structural variation, is related to carotid artery intima-media thickness (IMT), a surrogate marker for carotid atherosclerosis.
  
  
  METHODS
  As a cross-sectional study, we measured angle α in routine carotid artery ultrasounds from 176 subjects (130 men) with atherosclerotic disease/risk factors that attended Kouseiren Hospital in Kagoshima City, Japan between August 2007 and April 2009. We evaluated the correlation between the angle α and CCA- or ICA-IMT.
  
  
  RESULTS
  Angle α was weakly correlated with age but significantly correlated with ICA-IMT. The correlation was stronger in subjects with an ICA-IMT ≥ 0.5 mm than in those with an ICA-IMT < 0.5 mm (Right side r = 0.475 vs. 0.246, Left side r = 0.498 vs. 0.301, respectively). Upon multivariate logistic regression analysis, angle α and serum low-density lipoprotein cholesterol were independent explanatory variables for ICA-IMT.
  
  
  CONCLUSIONS
  Angle α is related to ICA-IMT in subjects with atherosclerotic disease or risk factors in this study.
authors.affiliation: Department of Hygiene and Health Promotion Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Daitoku
authors.forename: Toshinori
authors.initials: T
authors.lastname: Yuasa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tsunenari
authors.forename: Shigeho
authors.initials: S
authors.lastname: Maenohara
authors.forename: Kazuharu
authors.initials: K
authors.lastname: Mine
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Tamatsu
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Shimada
authors.forename: Chihaya
authors.initials: C
authors.lastname: Koriyama
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Ohishi
authors.forename: Masahisa
authors.initials: M
authors.lastname: Horiuchi
mesh_terms: D000328:Adult; D000368:Aged; D050197:Atherosclerosis / Q000453:epidemiology* / Q000473:pathology*; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging* / Q000473:pathology; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000473:pathology; D059168:Carotid Intima-Media Thickness; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors