title: Assessment of Collateral Status by Dynamic CT Angiography in Acute MCA Stroke: Timing of Acquisition and Relationship with Final Infarct Volume.
abstract: Dynamic CTA is a promising technique for visualization of collateral filling in patients with acute ischemic stroke. Our aim was to describe collateral filling with dynamic CTA and assess the relationship with infarct volume at follow-up.
  
  
  
  We selected patients with acute ischemic stroke due to proximal MCA occlusion. Patients underwent NCCT, single-phase CTA, and whole-brain CT perfusion/dynamic CTA within 9 hours after stroke onset. For each patient, a detailed assessment of the extent and velocity of arterial filling was obtained. Poor radiologic outcome was defined as an infarct volume of ≥70 mL. The association between collateral score and follow-up infarct volume was analyzed with Poisson regression.
  
  
  
  Sixty-one patients with a mean age of 67 years were included. For all patients combined, the interval that contained the peak of arterial filling in both hemispheres was between 11 and 21 seconds after ICA contrast entry. Poor collateral status as assessed with dynamic CTA was more strongly associated with infarct volume of ≥70 mL (risk ratio, 1.9; 95% CI, 1.3-2.9) than with single-phase CTA (risk ratio, 1.4; 95% CI, 0.8-2.5). Four subgroups (good-versus-poor and fast-versus-slow collaterals) were analyzed separately; the results showed that compared with good and fast collaterals, a similar risk ratio was found for patients with good-but-slow collaterals (risk ratio, 1.3; 95% CI, 0.7-2.4).
  
  
  
  Dynamic CTA provides a more detailed assessment of collaterals than single-phase CTA and has a stronger relationship with infarct volume at follow-up. The extent of collateral flow is more important in determining tissue fate than the velocity of collateral filling. The timing of dynamic CTA acquisition in relation to intravenous contrast administration is critical for the optimal assessment of the extent of collaterals.
authors.affiliation: From the Departments of Radiology (I.R.v.d.W., G.H., M.A.A.v.W.) Department of Neurology (I.R.v.d.W., J.B.), Medical Center Haaglanden, the Hague, the Netherlands wijngaardido@gmail.com.
authors.forename: I R
authors.identifier: 0000-0002-3734-6086
authors.initials: IR
authors.lastname: van den Wijngaard
authors.affiliation: From the Departments of Radiology (I.R.v.d.W., G.H., M.A.A.v.W.).
authors.forename: G
authors.identifier: 0000-0002-9788-4345
authors.initials: G
authors.lastname: Holswilder
authors.affiliation: Neurology (M.J.H.W.).
authors.forename: M J H
authors.identifier: 0000-0002-6838-9521
authors.initials: MJ
authors.lastname: Wermer
authors.affiliation: Department of Neurology (I.R.v.d.W., J.B.), Medical Center Haaglanden, the Hague, the Netherlands.
authors.forename: J
authors.identifier: 0000-0002-8850-8225
authors.initials: J
authors.lastname: Boiten
authors.affiliation: Clinical Epidemiology (A.A.), Leiden University Medical Center, Leiden, the Netherlands Department of Neurology and Neurosurgery (A.A.), Brain Center Rudolf Magnus.
authors.forename: A
authors.identifier: 0000-0003-2858-5808
authors.initials: A
authors.lastname: Algra
authors.affiliation: Department of Neurology (D.W.J.D.), Erasmus University Medical Center, Rotterdam, the Netherlands.
authors.forename: D W J
authors.identifier: 0000-0002-9234-3515
authors.initials: DW
authors.lastname: Dippel
authors.affiliation: Department of Radiology (J.W.D., B.K.V.), University Medical Center Utrecht, Utrecht, the Netherlands.
authors.forename: J W
authors.identifier: 0000-0003-4646-9587
authors.initials: JW
authors.lastname: Dankbaar
authors.affiliation: Department of Radiology (J.W.D., B.K.V.), University Medical Center Utrecht, Utrecht, the Netherlands.
authors.forename: B K
authors.identifier: 0000-0002-2542-9474
authors.initials: BK
authors.lastname: Velthuis
authors.affiliation: Departments of Radiology (A.M.M.B., C.B.L.M.M.) Biomedical Engineering and Physics (A.M.M.B.), Academic Medical Center, Amsterdam, the Netherlands.
authors.forename: A M M
authors.identifier: 0000-0002-3950-1561
authors.initials: AM
authors.lastname: Boers
authors.affiliation: Departments of Radiology (A.M.M.B., C.B.L.M.M.).
authors.forename: C B L M
authors.identifier: 0000-0002-7600-9568
authors.initials: CB
authors.lastname: Majoie
authors.affiliation: From the Departments of Radiology (I.R.v.d.W., G.H., M.A.A.v.W.).
authors.forename: M A A
authors.identifier: 0000-0003-4895-229X
authors.initials: MA
authors.lastname: van Walderveen
mesh_terms: D000368:Aged; D002533:Cerebral Angiography; D003097:Collateral Circulation; D000072226:Computed Tomography Angiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D020521:Stroke / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D016896:Treatment Outcome