Presentation
Witnessed loss of consciousness without warning. No head injury. Chronic hypocalcemia with hypoparathyroidism and vitamin D deficiency. Also known hypertension, congestive cardiac failure, and mixed vascular and Alzheimer dementia.
Patient Data
Florid bilateral calcification of the globi pallidi, putamina, caudate, posterior thalami, cerebellar hemispheres, especially in dentate nuclei, and extending into middle cerebellar peduncles, corona radiata, and subcortical white matter.
Case Discussion
In terms of diagnostic certainty, this is definitely Fahr syndrome. However whether it is secondary to hypoparathyroidism is harder to be definitive about especially in an individual with many comorbidities.
Fahr syndrome, is the name given to this distinctive pattern of intra-axial brain calcification. Calcification is especially prominent in the basal ganglia, dentate nuclei (of the cerebellum), thalamus and centrum semiovale 1. The term Fahr disease is often reserved for those with this pattern of brain calcification in whom it runs in the family, no secondary cause is evident, i.e. it seems to be idiopathic, and the patients tend to be middle-aged. However some use the terms Fahr disease and syndrome in a synonymous fashion.
This CT appearance may be associated with a broad range of neurological and/or psychiatric phenomena, although in many it is an incidental finding with no associated sequelae.
A long list of conditions have been associated with Fahr syndrome. Hypoparathyroidism is usually quoted as the commonest/classic association, although several other diseases of calcium metabolism, perhaps unsurprisingly, are also often listed. Other associations include vasculitides, infections, several neurogenetic entities and some cranial insults, e.g. radiotherapy, carbon monoxide poisoning and chemotherapy.