Poster Presentation Asia Pacific Stroke Conference 2024

Validation of CT perfusion based Vascular territory mapping: Correlation to visual pial grading and outcome measures (#457)

Michael Valente 1 2 , Mark Parsons 3 , Bernard Yan 2 , Chushuang Chen 3 4 , Milanka Visser 2 , Henry Ma 1 , Andrew Bivard 2
  1. Department of Neurology, Monash Health, Clayton, VIC, Australia
  2. Department of Medicine and Neurology, Melbourne Brain Centre at the Royal Melbourne Hospital, University of Melbourne, Parkville, Australia
  3. University of New South Wales South Western Sydney Clinical School, Department of Neurology Liverpool Hospital, Ingham Institute of Applied Medical Research, Liverpool, Australia
  4. Faculty of Medicine, University of NSW, Sydney, NSW, Australia

Vascular territory mapping (VTM) software estimates which intracerebral vessel provides peak arterial flow to a brain voxel. We hypothesize that the VTM algorithm may correlate to visual measurements of leptomeningeal grading and stroke outcome measures.

Methods

Consecutive patients with acute ischemic stroke and M1 MCA occlusion were recruited from the INSPIRE database (International Stroke Perfusion Imaging Registry). VTM software assigned regions of the brain to an estimated feeding vessel (ACA, MCA, PCA). Whole brain dynamic CTA was used to detect retrograde filling from pial arteries in the MCA territory. Collateral grading scores were based on origin (ACA/PCA) and extent of retrograde flow. Patients were pooled to assess relationships between VTM variables, collateral grades, and clinical outcomes.

Results

The final dataset included 115 patients with M1 occlusion. 64% had higher posterior collateral grading scores, 26% had equal grading and 25% had higher anterior grading. With regards to posterior collateral grade, ischaemic core and VTM-oPCA were significantly associated with decreased posterior collateral grade. An increase in VTM-oPCA was associated with an odds decrease in posterior collateral grade of 0.984 (95% CI, 0.99-1.0), p=0.001. VTM variables were not predictive of anterior collateral grade or stroke outcome measures.

Conclusion

VTM volumes did not correlate with visualized collateral vessels as hypothesized. An unanticipated inverse association between VTM-oPCA and posterior collateral grade was identified. It is unlikely that VTM volumes correlate with directional visual pial collateral grade.