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Updated: Dec 31, 2025

Simultaneous PET/MRI Imaging During Mouse Cerebral Hypoxia-ischemia
Published on: September 20, 2015
Interobserver Variability in the Recognition of Hypoxic-Ischemic Brain Injury on Computed Tomography Soon After
Andrew Caraganis1, Maximilian Mulder2, Robert R Kempainen3
1Division of Pulmonary, Allergy, Critical Care and Sleep, University of Minnesota, MMC #276, 420 Delaware St SE, Minneapolis, MN, USA. andrewc@umn.edu.
Background:
Cerebral edema and loss of gray-white matter differentiation on head computed tomography (CT) after cardiac arrest generally portend a poor prognosis. The interobserver variability in physician recognition of hypoxic-ischemic brain injury (HIBI) on early CT after out-of-hospital cardiac arrest has not been studied.
Methods:
In this survey study, participating physicians and a neuroradiologist reviewed 20 randomly selected head CTs obtained within 2 h of out-of-hospital cardiac arrest and decided if HIBI was present. All participants were blinded to clinical details. Interobserver agreement on the presence of HIBI (primary outcome) and pairwise agreement between participants and the neuroradiologist (secondary outcome) were determined using multi- and dual-rater kappa statistics with 95% confidence intervals (CIs).
Results:
Agreement among physicians regarding the presence of HIBI on head CT was fair (kappa 0.34; 95% CI 0.19-0.49). Individual physician agreement with the neuroradiologist varied from poor to moderate (kappa 0.0-0.48), with 8 of 10 physicians having no more than fair agreement. Regarding the perceived severity of HIBI on head CT, physician agreement was moderate (ICC = 0.56; 95% CI 0.38-0.77).
Conclusion:
Physicians, including radiologists, demonstrated substantial interobserver variability when identifying HIBI on head CT soon after out-of-hospital cardiac arrest.

