Clinical Report: Choreiform Dyskinesias After Heat Stroke: An Uncommon MRI Pattern
Overview
Neurological injury after heat stroke may become apparent after systemic organ failure has resolved. This report describes bilateral globus pallidus lesions on MRI in a patient who developed choreiform and dystonic movements after heat stroke. It highlights the importance of evaluating new neurological abnormalities after sedation is withdrawn.
Background
Heat stroke is a life-threatening condition that can cause neurological injury. Cerebellar involvement is a commonly reported neuroimaging finding, consistent with the vulnerability of Purkinje cells to hyperthermia. Bilateral globus pallidus lesions have also been reported, though less commonly. The proposed mechanisms of pallidal injury, including metabolic demand, mitochondrial dysfunction, excitotoxicity, and microvascular injury, are hypotheses rather than established explanations.
Key Findings
New neurological abnormalities or movement disorders after heat stroke, including those noted after sedation is withdrawn, may warrant brain MRI evaluation.
Cerebellar involvement is a commonly reported neuroimaging finding in heat stroke.
Bilateral globus pallidus lesions are an uncommon reported MRI finding after heat stroke.
The reported patient developed choreiform and dystonic movements in association with pallidal lesions. The proposed relationship to disruption of motor-circuit inhibition is an interpretation, not a proven mechanism.
In the reported patient, the pallidal lesions did not account for persistent impaired consciousness. Delayed awakening was considered multifactorial in the setting of acute kidney and liver injury, sedative and other drug exposure, and probable toxic-metabolic encephalopathy.
Conclusion
Bilateral globus pallidus lesions are an uncommon reported MRI finding after heat stroke and may occur alongside choreiform or dystonic movements. This case adds to the reported neuroimaging patterns associated with heat stroke; it does not establish the frequency, mechanism, or prognosis of this finding.
Related Resources & Content
Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Heat Illness: 2024 Update
How Can Heatstroke Damage the Brain? A Mini Review
Substantia Nigra Involvement: An Unusual Finding in Heat Stroke
