Isolated posterior cerebral artery (PCA) occlusions, which account for 5% of ischemic strokes, significantly impact patient quality of life due to effects on the thalamus and visual cortex. Current guidelines for acute treatment and the prognostic utility of perfusion imaging in PCA strokes remain limited and underexplored.
Methods
We conducted a retrospective analysis of 21 patients with isolated PCA occlusions from January 2017 to March 2023 at two comprehensive medical institutions. Perfusion imaging parameters, including time-to-maximum (Tmax) > 4 s, Tmax > 6 s, Tmax > 8 s, Tmax > 10 s, and mismatch volume, were extracted. The primary outcome was the modified Rankin Scale (mRS) score at 90 days.
Results
The median age of patients was 70 years, with 62% being male. Time-to-maximum > 4 s volume (rho = 0.46, 95% CI, 0.1–0.71, p = 0.036) and Tmax > 6 s volume (rho = 0.45, 95% CI, 0.09–0.71, p = 0.04) showed significant positive correlations with 90-day mRS scores. Other perfusion parameters, such as Tmax > 8 s volume and mismatch volume, approached statistical significance, while rCBF and hypoperfusion intensity ratio did not show significant correlations.
Conclusions
Perfusion imaging parameters, particularly Tmax tissue volumes, are correlated with long-term clinical outcomes in patients with isolated PCA occlusions. These findings support the potential role of perfusion imaging in the prognostic assessment and management of PCA stroke patients. Future studies with larger cohorts are warranted to confirm these results and to establish standardized perfusion imaging protocols for PCA occlusions.
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