The following is a summary of “Association between quantitative analysis of cerebral edema using CT imaging and neurological outcomes in cardiac arrest survivors,” published in the April 2024 issue of Emergency Medicine by In, et al.

For a study, researchers sought to assess whether the density distribution proportion of Hounsfield units (HUdp) in head computed tomography (HCT) images could serve as a quantitative measure of cerebral edema in survivors of out-of-hospital cardiac arrest (OHCA).

The retrospective observational study enrolled adult comatose OHCA survivors who underwent HCT within 6 hours (first scan) and 72–96 hours (second scan), all conducted using the same CT scanner. Semi-automated quantitative analysis was employed to detect disparities in HUdp at specific HU ranges across the intracranial component based on neurological outcomes. Cerebral edema was defined as the increased displacement of the sum of HUdp values (ΔHUdp) at a specific range between the two HCT scans. Poor neurological outcome was defined as cerebral performance categories 3–5 at 6 months post-OHCA.

Among 55 patients, 23 (42%) had a poor neurological outcome. Significant HUdp differences were noted between excellent and poor neurological outcomes in the second HCT scan at HU ranges of 1–14, 23–35, and 39–56 (all P < 0.05). Solely, the ΔHUdp = 23–35 range displayed a significant increase and correlation in the poor neurological outcome group (4.90 vs. -0.72, P < 0.001), alongside a cumulative decrease in the other two ranges (r = 0.97, P < 0.001). Multivariate logistic regression analysis revealed a significant association between ΔHUdp = 23–35 range and poor neurological outcomes (adjusted OR, 1.12; 95% CI: 1.02–1.24; P = 0.02).

The cohort study highlighted that an augmented displacement in the ΔHUdp = 23–35 range independently correlates with poor neurological outcomes, quantitatively evaluating cerebral edema formation in OHCA survivors.

Reference: sciencedirect.com/science/article/abs/pii/S0735675723007155