Diagnosis
Carbon monoxide poisoning
Findings
An axial computed tomography (CT) image shows focal hypodensity in the globus pallidi bilaterally. Axial magnetic resonance (MR) diffusion-weighted imaging (DWI) shows corresponding regions of diffusion restriction.
Discussion
Carbon monoxide (CO) poisoning most commonly occurs in the setting of attempted suicide or with the use of coal heaters in poorly ventilated homes. Toxicity occurs through formation of carboxyhemoglobin and direct mitochondrial damage. Clinical findings vary depending on exposure. Acute toxicity typically results in nausea, vomiting, and headache and may lead to confusion, cognitive impairment, loss of consciousness, seizures, coma, or death. Survivors may manifest movement disorders, hypertonia, short-term memory loss, and mental deterioration with delayed neurologic sequelae in 10% to 30% of victims.
CT demonstrates symmetric bilaterally low-attenuation in the globus pallidus and white matter. Basal ganglia diffusion restriction with corresponding T2 hyperintensity is characteristic in the acute setting. T1 shortening with gradient-echo susceptibility may be seen if hemorrhage is present.
- Sener RN. Acute carbon monoxide poisoning: Diffusion MR imaging findings. AJNR Am J Neuroradiol. 2003;24:1475-1477.
- Lo CP, Chen SY, Lee KW, et al. Brain injury after acute carbon monoxide poisoning: Early and late complications. AJR Am J Roentgenol. 2007;189:W205-211.