When symmetric basal ganglia calcification is found on CT, work through the differential systematically including Fahr disease, hypoparathyroidism, and infectious causes before accepting an idiopathic label. When PKAN is clinically suspected, obtain a brain MRI specifically to look for the eye of the tiger sign in the globus pallidus, because it is a highly specific imaging marker that can confirm the diagnosis without biopsy.

Underlying mechanism involves a genetic pantothenate kinase deficiency, which directly leads to excessive, toxic iron deposition right in the globus pallidus; Individuals typically exhibit early psychiatric symptoms first; As they reach middle age, this is characteristically followed by progressive dementia and parkinsonism; Specific category of neurodegenerative disorders, which includes conditions such as pantothenate kinase-associated neurodegeneration, or PKAN; On a non-contrast brain CT scan, you will see very striking, extensive calcification within the basal ganglia, the dentate nuclei, and the periventricular regions