Quantitative assessment of collateral time on perfusion computed tomography in acute ischemic stroke patients

Yao Xu; Jianhong Yang; Xiang Gao; Jie Sun; Qing Shang; Qing Han; Yuefei Wu; Jichuan Li; Tianqi Xu; Yi Huang; Yuning Pan; Mark W Parson; Longting Lin

doi:10.3389/fneur.2023.1230697

Quantitative assessment of collateral time on perfusion computed tomography in acute ischemic stroke patients

Front Neurol. 2023 Aug 24:14:1230697. doi: 10.3389/fneur.2023.1230697. eCollection 2023.

Authors

Yao Xu^#¹, Jianhong Yang^#¹, Xiang Gao², Jie Sun², Qing Shang¹, Qing Han¹, Yuefei Wu¹, Jichuan Li¹, Tianqi Xu¹, Yi Huang^{2

3}, Yuning Pan⁴, Mark W Parson^{5

6}, Longting Lin^{1

5}

Affiliations

¹ Department of Neurology, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang, China.
² Department of Neurosurgery, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang, China.
³ Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province, Ningbo, China.
⁴ Department of Radiology, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang, China.
⁵ Sydney Brain Center, University of New South Wales, Sydney, NSW, Australia.
⁶ Department of Neurology, Liverpool Hospital, Sydney, NSW, Australia.

^# Contributed equally.

Abstract

Background and aim: Good collateral circulation is recognized to maintain perfusion and contribute to favorable clinical outcomes in acute ischemic stroke. This study aimed to derive and validate an optimal collateral time measurement on perfusion computed tomography imaging for patients with acute ischemic stroke.

Methods: This study included 106 acute ischemic stroke patients with complete large vessel occlusions. In deriving cohort of 23 patients, the parasagittal region of the ischemic hemisphere was divided into six pial arterial zones according to pial branches of the middle cerebral artery. Within the 85 arterial zones with collateral vessels, the receiver operating characteristic analysis was performed to derive the optimal collateral time threshold for fast collateral flow on perfusion computed tomography. The reference for fast collateral flow was the peak contrast delay on the collateral vessels within each ischemic arterial zone compared to its contralateral normal arterial zone on dynamic computed tomography angiography. The optimal perfusion collateral time threshold was then tested in predicting poor clinical outcomes (modified Rankin score of 5-6) and final infarct volume in the validation cohort of 83 patients.

Results: For the derivation cohort of 85 arterial zones, the optimal collateral time threshold for fast collateral flow on perfusion computed tomography was a delay time of 4.04 s [area under the curve = 0.78 (0.67, 0.89), sensitivity = 73%, and specificity = 77%]. Therefore, the delay time of 4 s was used to define the perfusion collateral time. In the validation cohort, the perfusion collateral time showed a slightly higher predicting power than dynamic computed tomography angiography collateral time in poor clinical outcomes (area under the curve = 0.72 vs. 0.67; P < 0.001). Compared to dynamic computed tomography angiography collateral time, the perfusion collateral time also had better performance in predicting final infarct volume (R-squared values = 0.55 vs. 0.23; P < 0.001).

Conclusion: Our results indicate that perfusion computed tomography can accurately quantify the collateral time after acute ischemic stroke.

Keywords: collateral velocity; computed tomography; perfusion imaging; quantitative assessment; stroke.

Grants and funding

This study was supported by Ningbo Health Branding Subject Fund (PPXK2018-04), Ningbo Top Medical and Health Research Program (No. 2022020304), Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province (2022E10026), Medicine and Health Science and Technology Projects of Zhejiang Province (2019KY162, 2020KY831, and 2022KY302), and Ningbo Science and Technology Innovation 2025 Major Project (2022Z134).