Peak Perihemorrhagic Edema Volume Predicts Functional Outcome After Intracerebral Hemorrhage

Predictions about functional outcome after intracerebral hemorrhage (ICH) are often based on factors available at initial presentation, such as age, initial hematoma volume and location, intraventricular hemorrhage, and NIH Stroke Scale score. But as the hematoma evolves, the extent of perihemorrhagic edema that develops over the subsequent 8 to 12 days could provide both additional prognostic information and insight into mechanisms of secondary injury after ICH, because perihemorrhagic edema is correlated with secondary processes such as inflammation and degradation of heme products.

In this retrospective, single-center study, investigators identified 292 patients with supratentorial primary intracerebral hemorrhage with serial computed tomography (CT) scans and 90-day functional outcome data available for analysis. The volume of perihemorrhagic edema was determined from CT scans using a semiautomated software algorithm, and good outcome was defined as a modified Rankin scale score of 3 or less at 90 days.

Larger peak perihemorrhagic edema volume was independently associated with worse functional outcomes after adjustment for established prognostic factors (odds ratio for good outcome per mL of peak perihemorrhagic edema volume, 0.98; 95% confidence interval, 0.97–0.99). Patients with greater peak perihemorrhagic edema volume tended to have more perihemorrhagic edema already within the first 3 days and, in a propensity score–matched subgroup analysis, a higher neutrophil-to-lymphocyte ratio (a potential marker for inflammation) on day 6 after adjustment for age, hemorrhage volume, and hematoma location.