CSF-Based Volumetric Imaging Biomarkers Highlight Incidence and Risk Factors for Cerebral Edema After Ischemic Stroke

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Cerebral edema is a critical stroke complication.
• Traditional endpoints like midline shift miss early or mild edema.
• Need for quantitative biomarkers to assess the full spectrum of edema.

Purpose of the Study:

• Develop and validate quantitative imaging biomarkers for cerebral edema.
• Assess the relationship between these biomarkers and stroke severity.
• Determine the association of edema biomarkers with stroke outcomes.

Main Methods:

• Automated image analysis of follow-up CT scans in 935 stroke patients.
• Measurement of cerebrospinal fluid (CSF) displacement (ΔCSF) and CSF volume ratio.
• Correlation with midline shift and assessment of clinical/radiographic predictors and stroke outcome (modified Rankin Scale).

Main Results:

• ΔCSF and CSF ratio correlated with midline shift but offered broader detection.
• Thresholds identified over half of patients with edema, compared to 14% with midline shift.
• Edema predictors include stroke severity and vascular risk factors (hypertension, diabetes).
• Both ΔCSF and lower CSF ratio associated with worse stroke outcomes.

Conclusions:

• Volumetric CSF shift biomarkers effectively measure cerebral edema in most stroke patients.
• Edema detection is improved, including in cases without visible midline shift.
• Edema is influenced by stroke severity and vascular risk factors, impacting patient outcomes.