A rare characteristic neuroimaging pattern in hyperammonaemia

Hyperammonaemia is a potentially life-threatening condition that is often neglected diagnostically. It presents with non-specific symptoms, such as encephalopathy. Delayed recognition leads to potentially irreversible neurological damage. We report 3 patients who on magnetic resonance imaging (MRI) of brain demonstrated a rare pattern of cortical signal change, which spared the perirolandic cortex. This characteristic radiological pattern should prompt immediate testing for raised serum ammonia, facilitating early treatment for this disorder.