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.
Keywords: Angiography, collateral, outcome, perfusion, pial, stroke