Cerebrospinal Fluid Volume Assessed from Clinical t1w-mri Does Not Predict Occurrence or Severity of Hemorrhagic Transformation Post-thrombectomy

Introduction: Hemorrhagic transformation (HT) is a serious reperfusion complication of endovascular treatment (EVT) for large vessel occlusion strokes. This necessitates the importance to identify imaging biomarkers for increased risk of HT post EVT. Our study aims to assess if cerebrospinal fluid volume (CSFV) can predict the risk or severity of HT. We chose CSFV because we previously found it to be significantly predictive of functional outcomes post EVT.

Methods: We performed a retrospective analysis of a single center Stroke Thrombectomy and Aneurysm Registry database collected between 2015 - 2021. 213 patients were selected (mean age 67.5 ± 14.6, 49.3% female) who had adequate quality MRI within 14 days of EVT, along with HT status. Of the 213 patients, 103 patients with confirmed HT occurrence were classified for hemorrhage severity using the European Cooperative Acute Stroke Study (ECASS) scale.

Results: Hemorrhagic conversion was demonstrated on CT in 103/213 cases; 71 were petechial (H1/2), 24 were parenchymal (PH1/2), 7 were subarachnoid, and 1 was intraventricular. However, only 13/103 were symptomatic hemorrhages. We have shown that CSFV inversely predicted 90-day functional mRS outcomes (p < 0.001). Nonetheless, CSFV did not significantly predict HT in a logistic regression model, nor did it predict severity of HT based on ECASS classification in an ordinal regression model. CSFV was not predictive of HT occurrence or severity even after adjusting for covariates consisting of age, sex, hypertension, hemoglobin A1c, and National Institutes of Health Stroke Scale score (NIHSS) upon admission. Consistent with current literature, NIHSS upon admission significantly predicted risk of HT occurrence (p=0.044) and severity of HT (p=0.034).

Conclusion : Pre-existing brain health as measured by CSFV may be an important prognostic biomarker. However, CSFV does not seem to correlate with the propensity nor severity of hemorrhagic transformation post-thrombectomy.