Assessment of Collateral Status by Dynamic CT Angiography in Acute MCA Stroke: Timing of Acquisition and Relationship with Final Infarct Volume

BACKGROUND AND PURPOSE: 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. MATERIALS AND METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

[1]  A. Algra,et al.  Impact of Collateral Status Evaluated by Dynamic Computed Tomographic Angiography on Clinical Outcome in Patients With Ischemic Stroke , 2015, Stroke.

[2]  Hester F. Lingsma,et al.  Value of Computed Tomographic Perfusion–Based Patient Selection for Intra-Arterial Acute Ischemic Stroke Treatment , 2015, Stroke.

[3]  Eric E. Smith,et al.  Randomized assessment of rapid endovascular treatment of ischemic stroke. , 2015, The New England journal of medicine.

[4]  B. Ertl-Wagner,et al.  Strategies of Collateral Blood Flow Assessment in Ischemic Stroke: Prediction of the Follow-Up Infarct Volume in Conventional and Dynamic CTA , 2015, American Journal of Neuroradiology.

[5]  A. Demchuk,et al.  Multiphase CT Angiography: A New Tool for the Imaging Triage of Patients with Acute Ischemic Stroke. , 2015, Radiology.

[6]  M. Wiesmann,et al.  Collateral vessels in proximal middle cerebral artery occlusion: the ENDOSTROKE study. , 2015, Radiology.

[7]  Hester F. Lingsma,et al.  MR CLEAN, a multicenter randomized clinical trial of endovascular treatment for acute ischemic stroke in the Netherlands: study protocol for a randomized controlled trial , 2014, Trials.

[8]  Joseph P Broderick,et al.  Collaterals at Angiography and Outcomes in the Interventional Management of Stroke (IMS) III Trial , 2014, Stroke.

[9]  Geert Jan Biessels,et al.  Prediction of outcome in patients with suspected acute ischaemic stroke with CT perfusion and CT angiography: the Dutch acute stroke trial (DUST) study protocol , 2014, BMC Neurology.

[10]  K. Furie,et al.  Prognosis of untreated strokes due to anterior circulation proximal intracranial arterial occlusions detected by use of computed tomography angiography. , 2014, JAMA neurology.

[11]  Ernst Klotz,et al.  Time-resolved assessment of collateral flow using 4D CT angiography in large-vessel occlusion stroke , 2014, European Radiology.

[12]  Bram van Ginneken,et al.  Timing-Invariant Imaging of Collateral Vessels in Acute Ischemic Stroke , 2013, Stroke.

[13]  L. Beenen,et al.  Automated Cerebral Infarct Volume Measurement in Follow-up Noncontrast CT Scans of Patients with Acute Ischemic Stroke , 2013, American Journal of Neuroradiology.

[14]  A. Demchuk,et al.  Assessment of Leptomeningeal Collaterals Using Dynamic CT Angiography in Patients with Acute Ischemic Stroke , 2013, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[15]  Z. Chaudhry,et al.  Malignant CTA Collateral Profile Is Highly Specific for Large Admission DWI Infarct Core and Poor Outcome in Acute Stroke , 2012, American Journal of Neuroradiology.

[16]  A. Demchuk,et al.  Regional Leptomeningeal Score on CT Angiography Predicts Clinical and Imaging Outcomes in Patients with Acute Anterior Circulation Occlusions , 2011, American Journal of Neuroradiology.

[17]  S. Warach,et al.  Recommendations for imaging of acute ischemic stroke: a scientific statement from the American Heart Association. , 2009, Stroke.

[18]  K. Furie,et al.  Collateral Vessels on CT Angiography Predict Outcome in Acute Ischemic Stroke , 2009, Stroke.

[19]  A. Demchuk,et al.  Intracranial Thrombus Extent Predicts Clinical Outcome, Final Infarct Size and Hemorrhagic Transformation in Ischemic Stroke: The Clot Burden Score , 2008, International journal of stroke : official journal of the International Stroke Society.

[20]  M. Wintermark,et al.  Systematic comparison of perfusion‐CT and CT‐angiography in acute stroke patients , 2007, Annals of neurology.

[21]  R. Higashida,et al.  Trial Design and Reporting Standards for Intra-Arterial Cerebral Thrombolysis for Acute Ischemic Stroke , 2003, Stroke.

[22]  A. Demchuk,et al.  Validity and reliability of a quantitative computed tomography score in predicting outcome of hyperacute stroke before thrombolytic therapy , 2000, The Lancet.

[23]  A. Satterfield,et al.  TREATMENT , 1924, California and western medicine.

[24]  A. Demchuk,et al.  Validity and reliability of a quantitative computed tomography score in predicting outcome of hyperacute stroke before thrombolytic therapy. ASPECTS Study Group. Alberta Stroke Programme Early CT Score. , 2000, Lancet.