Reperfusion facilitates reversible disruption of the human blood-brain barrier following acute ischaemic stroke.

OBJECTIVES: We aimed to detect early changes of the blood-brain barrier permeability (BBBP) in acute ischaemic stroke (AIS), with or without reperfusion, and find out whether BBBP can predict clinical outcomes.

METHODS: Consecutive AIS patients imaged with computed tomographic perfusion (CTP) before and 24 h after treatment were included. The relative permeability-surface area product (rPS) was calculated within the hypoperfused region (rPShypo-i ), non-hypoperfused region of ischaemic hemisphere (rPSnonhypo-i ) and their contralateral mirror regions (rPShypo-c and rPSnonhypo-c ). The changes of rPS were analysed using analysis of variance (ANOVA) with repeated measures. Logistic regression was used to identify independent predictors of unfavourable outcome.

RESULTS: Fifty-six patients were included in the analysis, median age was 76 (IQR 62-81) years and 28 (50%) were female. From baseline to 24 h after treatment, rPShypo-i , rPSnonhypo-i and rPShypo-c all decreased significantly. The decreases in rPShypo-i and rPShypo-c were larger in the reperfusion group than non-reperfusion group. The rPShypo-i at follow-up was a predictor for unfavourable outcome (OR 1.131; 95% CI 1.018-1.256; P = 0.022).

CONCLUSION: Early disruption of BBB in AIS is reversible, particularly when greater reperfusion is achieved. Elevated BBBP at 24 h after treatment, not the pretreatment BBBP, predicts unfavourable outcome.

KEY POINTS: • Early disruption of blood-brain barrier (BBB) in stroke is reversible after treatment. • The reversibility of BBB permeability is associated with reperfusion. • Unfavourable outcome is associated with BBB permeability at 24 h after treatment. • Contralateral non-ischaemic hemisphere is not 'normal' during an acute stroke.