Background Endovascular therapy (EVT) has revolutionized the treatment of acute stroke, but large vessel recanalization does not always result in tissue-level reperfusion. Cerebral blood flow (CBF) is not routinely monitored during EVT. We aimed to leverage diffuse correlation spectroscopy (DCS), a novel transcranial optical imaging technique, to assess the relationship between microvascular CBF and post-EVT outcomes.
Methods Frontal lobe CBF was monitored by DCS in 40 patients undergoing EVT. Baseline CBF deficit was calculated as the percentage of CBF impairment on pre-EVT CT perfusion. Microvascular reperfusion was calculated as the percentage increase in DCS-derived CBF that occurred with recanalization. The adequacy of reperfusion was defined by persistent CBF deficit, calculated as: baseline CBF deficit − microvascular reperfusion. A good functional outcome was defined as 90-day modified Rankin Scale score ≤2.
Results Thirty-six of 40 patients achieved successful recanalization, in whom microvascular reperfusion in itself was not associated with infarct volume or functional outcome. However, patients with good functional outcomes had a smaller persistent CBF deficit (median 1% (IQR −11%–16%)) than patients with poor outcomes (median 28% (IQR 2–50%)) (p=0.02). Smaller persistent CBF deficit was also associated with smaller infarct volume (p=0.004). Multivariate models confirmed that persistent CBF deficit was independently associated with infarct volume and functional outcome.
Conclusions CBF augmentation alone does not predict post-EVT outcomes, but when microvascular reperfusion closely matches the baseline CBF deficit, patients experience favorable clinical and radiographic outcomes. By recognizing inadequate reperfusion, bedside CBF monitoring may provide opportunities to personalize post-EVT care aimed at CBF optimization.
- blood flow
Data availability statement
The de-identified data that support the findings of this study will be made available by the corresponding author upon reasonable request.
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Correction notice Since this paper was first published, the author Omar A Choudhri has been added to the author list.
Contributors CGF: study design, data collection, data analysis, data interpretation, manuscript preparation, manuscript revisions. CGF is also responsible for the overall content as the guarantor. RMF: data collection, data processing, manuscript edits. SCa: data collection, database management, manuscript edits. WAK: study design, data interpretation, manuscript edits. SEK: study design, data analysis, manuscript preparation. WBB: data analysis, data interpretation, manuscript edits. AGY: study design, data processing, data interpretation, manuscript edits. SRM: data interpretation, manuscript edits. SCu: data collection, manuscript edits. DKK: data collection, data interpretation, manuscript edits. JKB: data collection, data interpretation, manuscript edits. BP: data collection, data interpretation, manuscript edits. VMS: data interpretation, manuscript edits. RWH: data collection, manuscript edits. JAD: study design, data analysis, data interpretation, manuscript preparation.
Funding This work was supported by the American Heart Association (19CDA-34630033, CGF) and National Institutes of Health (K23-NS110993, CGF; P41-EB01593, AGY; R21-NS126862, CGF & JAD; P41-EB029460, JAD).
Competing interests AGY has three patents potentially relevant to this work that do not currently generate income (United States patents 10,342,488; 10,827,976; and 6,076,010). JAD and AGY have one additional patent potentially relevant to this work that does not currently generate income (United States patent 8,082,015); CGF received an investigator initiated grant from OpenWater, not directly related to this study.
Provenance and peer review Not commissioned; externally peer reviewed.
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