Relationship Between Collateral Status, Infarct Growth and Outcome in Patients with Middle Cerebral Artery Occlusion by CT Angiography and CT Perfusion Imaging.

Abstract

Introduction: Unveiling the dynamic penumbra region represents another crucial stage in treating individuals with ischemic strokes. Our objective was to explore how collateral blood flow assessments using multiphasic (triphasic) CT angiography (mpCTA) and CT perfusion (CTP) examinations correlate with the expansion of infarcted areas and disability levels in patients with middle cerebral artery (MCA) M1 and M2 occlusion.

Methods: The research was carried out as a prospective, descriptive, case series study. mpCTA and CTP were performed while patients were referred to the emergency department. Baseline National Institutes of Health Stroke Scale (NIHSS), Modified Rankin Scale (mRS) and the Barthel Index for Activities of Daily Living at 3 months were calculated. The connection between perfusion parameters that represent penumbral information derived from CTP and collateral flow information obtained from mpCTA with infarct expansion and outcome was investigated.

Results: Thirty-six patients were included in the study. The mean age of the participants in the research was found 73.47±10.67. 52.8% of the individuals were male. 72.3% of the patients exhibited an unfavorable functional outcome according to mRS at 3 months. Based on the Menon collateral score from the mpCTA, the infarct expansion showed a statistically significant difference between the groups (p=0.037). The mRS scores at 3 months did not show a statistically significant difference between the groups according to the mpCTA Menon collateral score (p=0.073). Penumbra volume information obtained by using Tmax/CBV and CBF/CBV thresholds on CTP showed statistically significant differences among good and poor clinical outcome groups based on mRS at 3 months (respectively p=0.010, 0.029). The average MTT value within the penumbra obtained from the MTT/CBV map exhibited a statistically significant difference among the groups based on the mRS at 3 months (p=0.011). There was a weak but statistically significant relationship between the volume of the penumbra obtained from CTP maps created by selecting Tmax=6 sec and the infarct growth (p=0.028).

Conclusion: Final infarct volume and infarct growth can be predicted using collateral circulation data acquired through mpCTA. The patient's disability can be assessed by analyzing the penumbral MTT value and the penumbral volume data obtained from CTP maps generated using various threshold values. Moreover, penumbra volume obtained from CTP maps created by selecting Tmax as a threshold can give information about infarct growth.