title: Computational fluid dynamics modeling of symptomatic intracranial atherosclerosis may predict risk of stroke recurrence.
abstract: BACKGROUND
  Patients with symptomatic intracranial atherosclerosis (ICAS) of ≥ 70% luminal stenosis are at high risk of stroke recurrence. We aimed to evaluate the relationships between hemodynamics of ICAS revealed by computational fluid dynamics (CFD) models and risk of stroke recurrence in this patient subset.
  
  
  METHODS
  Patients with a symptomatic ICAS lesion of 70-99% luminal stenosis were screened and enrolled in this study. CFD models were reconstructed based on baseline computed tomographic angiography (CTA) source images, to reveal hemodynamics of the qualifying symptomatic ICAS lesions. Change of pressures across a lesion was represented by the ratio of post- and pre-stenotic pressures. Change of shear strain rates (SSR) across a lesion was represented by the ratio of SSRs at the stenotic throat and proximal normal vessel segment, similar for the change of flow velocities. Patients were followed up for 1 year.
  
  
  RESULTS
  Overall, 32 patients (median age 65; 59.4% males) were recruited. The median pressure, SSR and velocity ratios for the ICAS lesions were 0.40 (-2.46-0.79), 4.5 (2.2-20.6), and 7.4 (5.2-12.5), respectively. SSR ratio (hazard ratio [HR] 1.027; 95% confidence interval [CI], 1.004-1.051; P = 0.023) and velocity ratio (HR 1.029; 95% CI, 1.002-1.056; P = 0.035) were significantly related to recurrent territorial ischemic stroke within 1 year by univariate Cox regression, respectively with the c-statistics of 0.776 (95% CI, 0.594-0.903; P = 0.014) and 0.776 (95% CI, 0.594-0.903; P = 0.002) in receiver operating characteristic analysis.
  
  
  CONCLUSIONS
  Hemodynamics of ICAS on CFD models reconstructed from routinely obtained CTA images may predict subsequent stroke recurrence in patients with a symptomatic ICAS lesion of 70-99% luminal stenosis.
authors.affiliation: Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Leng
authors.affiliation: UCLA Stroke Center, Los Angeles, California, United States of America.
authors.forename: Fabien
authors.initials: F
authors.lastname: Scalzo
authors.affiliation: Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China.
authors.forename: Hing Lung
authors.initials: HL
authors.lastname: Ip
authors.affiliation: UCLA Stroke Center, Los Angeles, California, United States of America.
authors.forename: Mark
authors.initials: M
authors.lastname: Johnson
authors.affiliation: UCLA Stroke Center, Los Angeles, California, United States of America.
authors.forename: Albert K
authors.initials: AK
authors.lastname: Fong
authors.affiliation: Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China.
authors.forename: Florence S Y
authors.initials: FS
authors.lastname: Fan
authors.affiliation: Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China.
authors.forename: Xiangyan
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China.
authors.forename: Yannie O Y
authors.initials: YO
authors.lastname: Soo
authors.affiliation: Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Zhongrong
authors.initials: Z
authors.lastname: Miao
authors.affiliation: Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Neurology, Tufts University, Boston, Massachusetts, United States of America.
authors.forename: Edward
authors.initials: E
authors.lastname: Feldmann
authors.affiliation: Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China.
authors.forename: Thomas W H
authors.initials: TW
authors.lastname: Leung
authors.affiliation: UCLA Stroke Center, Los Angeles, California, United States of America.
authors.forename: David S
authors.initials: DS
authors.lastname: Liebeskind
authors.affiliation: Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China.
authors.forename: Ka Sing
authors.initials: KS
authors.lastname: Wong
mesh_terms: D000368:Aged; D003198:Computer Simulation; D005260:Female; D006439:Hemodynamics; D006801:Humans; D057446:Hydrodynamics; D002537:Intracranial Arteriosclerosis / Q000150:complications* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D012008:Recurrence; D012189:Retrospective Studies; D018570:Risk Assessment; D020521:Stroke / Q000150:complications*