Methanol intoxication-induced nigrostriatal dysfunction detected using 6-[18F]fluoro-L-dopa PET

Area of Science:

• Neuroscience
• Toxicology
• Radiochemistry

Background:

• Methanol poisoning can cause severe neurological deficits, including visual impairment and movement disorders.
• The precise neurochemical underpinnings of these deficits, particularly dopaminergic system involvement, require further elucidation.

Observation:

• A 49-year-old male presented with acute severe methanol intoxication after ingesting windshield washer fluid.
• Clinical manifestations included optic atrophy with blindness and an extrapyramidal syndrome.
• Brain MRI revealed putaminal injury and subcortical white matter hyperintensity.

Findings:

• Positron emission tomography (PET) scanning using 6-[18F]fluoro-L-dopa demonstrated symmetrical, impaired presynaptic dopaminergic activity in the striatum.
• Functional impairment of dopaminergic nigrostriatal neurons was indicated, with more severe reduction in the putamina (40% of controls) than caudate nuclei (60% of controls).
• This represents the first reported 18F-dopa PET scan findings in acute methanol poisoning.

Implications:

• 18F-dopa PET scanning can detect functional dopaminergic deficits in methanol intoxication.
• Findings suggest nigrostriatal dopaminergic pathway damage contributes to the extrapyramidal syndrome in methanol poisoning.
• This imaging technique may aid in understanding and potentially monitoring neurological sequelae of toxic exposures.