Clinical study Implementation of multiphase computed tomography angiography in management of patients with acute ischemic stroke in clinical practice Nattaphol Uransilp a , Pornpatr A. Dharmasaroja b,⇑ , Arvemas Watcharakorn b , Sombat Muengtaweepongsa a a Department of Internal Medicine, Faculty of Medicine, Thammasat University, Klong 1, Klong Luang, Pathumthani 12120, Thailand b Stroke and Neurodegenerative Diseases Research Unit, Faculty of Medicine, Thammasat University, Klong 1, Klong Luang, Pathumthani 12120, Thailand article info Article history: Received 7 September 2018 Accepted 10 December 2018 Available online xxxx Keywords: Multiphase CTA Computed tomography angiography Acute stroke Ischemic stroke Asian Thai abstract Multiphase computed tomography angiography (CTA) provides information on the status of major cranial arteries and extent of brain collateralization. The purpose of the study was to determine whether imple- mentation of multiphase CTA in routine clinical practice was feasible, safe and useful. Patients with acute ischemic stroke (NIHSS  6) were included. Multiphase CTA was performed. Duration of performing mul- tiphase CTA, inter-rater correlation and incidence of contrast-induced nephropathy (CIN) were studied. Infarct volume, incidence of hemorrhagic transformation, the rates of favorable outcome and death were compared between those with poor and intermediate-good collateralization. Multiphase CTA was per- formed in 108 patients. Mean duration on each multiphase CTA study was 4.8 min. Inter-rater reliability was intermediate-good (weighted kappa 0.7569, p < 0.001). CIN occurred in 3 patients (2.8%). There were no major intracranial/extracranial artery occlusion in 31 patients (29%) and there were severe stenosis or occlusions in 77 patients (71%). In the subgroup of patients with major artery severe stenosis or occlu- sion, 36 patients (36/77, 47%) had poor collateralization. Despite non-significant difference in acute treat- ment, the patients with poor collateralization had larger infarct (123 vs 35 cc, p < 0.001) and poorer outcomes (mean modified Rankin scale 3.86 vs 2.73, p = 0.011), while the differences in symptomatic hemorrhagic transformation (2.6 vs 7%, p = 0.385) and death rate (14 vs 12%, p = 0.825) were non- significant, as compared to those with intermediate-good collateralization. Multiphase CTA was feasible and safe. Besides the status of major arteries, multiphase CTA provided information on collateralization, which was associated with the size of infarct and clinical outcomes. Ó 2018 Elsevier Ltd. All rights reserved. 1. Introduction Mechanical thrombectomy has become the standard treatment for eligible patients with acute ischemic stroke. Patients should receive mechanical thrombectomy if they meet all the following criteria: (1) prestroke modified Ranking Scale (MRS) of 0 to 1, (2) causative occlusion of the internal carotid artery (ICA) or middle cerebral artery (MCA) segment1 (M1), (3) age 18, (4) NIHSS score of 6 and (6) treatment can be initiated (groin puncture) within 6 h of symptom onset [1]. Status of major cerebral arteries must be assessed before proceeding to perform mechanical thrombec- tomy. Computed tomography angiography (CTA) is widely avail- able and easily accessed. However, the clinical outcomes of patients after mechanical thrombectomy depend on many factors, one of which is the status of collateral circulation. Good collateral circulation was associated with better clinical outcomes, smaller infarct, increased recanalization rate and lower rate of hemor- rhagic transformation as compared to poor collateral circulation and may extend the time window for mechanical thrombectomy [2–5]. Both perfusion CT (CTP) and magnetic resonance imaging (MR) are susceptible to patient motion and require trained person- nel to process the data [6]. Multimodal CT (including non-contrast CT, CTA and CTP) require 2 doses of contrast media injection. Con- ventional angiography is an invasive method and has to be per- formed by an interventionist. Multiphase CTA was developed to provide information on degree and extent of pial arterial filling in the whole brain in a time-resolved manner [6]. However, this technology is rather new to apply in routine clinical practice and there is less information about incidence of contrast-induced nephropathy in Asian patients. We sought to determine whether implementation of multiphase CTA in clinical practice was feasible, https://doi.org/10.1016/j.jocn.2018.12.010 0967-5868/Ó 2018 Elsevier Ltd. All rights reserved. ⇑ Corresponding author at: Division of Neurology, Department of Internal Medicine, Faculty of Medicine, Thammasat University, Klong 1, Klong Luang, Pathumthani 12120, Thailand. E-mail address: pornpatr1@hotmail.com (P.A. Dharmasaroja). Journal of Clinical Neuroscience xxx (xxxx) xxx Contents lists available at ScienceDirect Journal of Clinical Neuroscience journal homepage: www.elsevier.com/locate/jocn Please cite this article as: N. Uransilp, P. A. Dharmasaroja, A. Watcharakorn et al., Implementation of multiphase computed tomography angiography in management of patients with acute ischemic stroke in clinical practice, Journal of Clinical Neuroscience, https://doi.org/10.1016/j.jocn.2018.12.010