Learning objectives
Identify the patterns of infarction in diffuse anoxic brain injury
Knowledge of the impact of MRI timing on the utility of various sequences
Relationship between imaging pattern observed and the clinical outcome for patients who are diagnosed with diffuse anoxic brain injury
Background
Diffuse anoxic brain injury is a well-recognised complication of severely impaired cardiac function, most commonly in the setting of out-of-hospital cardiac arrest. The MRI features of diffuse anoxic brain injury are sparsely described in the medical literature.
In addition to this, it can be a challenging diagnosis to make by imaging due to its occasionally subtle and typically symmetrical distribution [1]. We present a 9-year review of the main imaging findings of diffuse anoxic brain injury identified in a tertiary care setting.
Findings and procedure details
PROCEDURE DETAILS
We interrogated our institution’s Radiology Information System (RIS) for MRI brains performed under general anaesthesia within 14 days of suspected global ischaemic insult over a 9-year period.
472 scans were performed within this time period under those conditions. All scan reports were analysed by the lead author and were included in the study if the initial report was positive for anoxic brain injury. Demographics and clinical outcome measures were recorded by the lead author. Clinical outcome was adjudicated by calculating modified rankin score...
Conclusion
We identified consistent patterns of diffuse anoxic brain injury that are identifiable on MRI performed within 14 days of ischaemic insult. There is considerable overlap between the patterns of cortical injury and the deep nuclei. DWI is superior to FLAIR when imaging is performed within 5 day, outside that time-window, the two methods are equivocal for diagnosing DABI. FLAIR is typically superior to TSE-T2 sequences for diagnosis, although we did note that brainstem evaluation with T2 was frequently equivalent to FLAIR. Given the lack of...
Personal information and conflict of interest
Dr. S. P. Doran; Department of Radiology, St James Hospital, Dublin/IE - nothing to disclose.
[email protected]
Dr. M. Courtney; The Tom Mitchell Centre for Advanced Medical Imaging, St James Hospital,Dublin/IE - nothing to disclose.
Prof J. F. Meaney; Department of Radiology and The Tom Mitchell Centre for Advanced Medical Imaging,St James Hospital,Dublin/IE - nothing to disclose
References
Muttikal TJE, Wintermark M. MRI patterns of global hypoxic-ischaemic injury in adults. Journal of Neuroradiology. 2013. 40; 164-171
NunnA,BathPM,Gray LJ.Analysis of the modified Rankin Scale in randomised controlled trials of acute ischaemic stroke: a systematic review.Stroke Res Treat2016;9482876
Choi SP et al. Diffusion weighted magnetic resonance imaging for predicting the clinical outcome of comatose survivors after cardiac arrest: a cohort study. 2010. 14:R17
Takahashi S et al. Hypoxic brain damage: Cortical Laminar Necrosis and Delayed Changes in White Matter at Sequential MR Imaging. Radiology. 1993;...