Fahr's disease is characterized by idiopathic calcification of the basal ganglia and other brain regions. Clinically it may be accompanied by extrapyramidal and behavioural disorders. In Fahr's syndrome, the same pathology is due to another well-defined disease. Calcium/phosphate metabolic disorders, e.g. hypoparathyroidism or pseudohyperparathyroidism, may be involved. Here, we report a case of 62-year-old man presenting with severe dementia but only mild movement disorders and mild calcium metabolism abnormalities. Extensive brain calcifications together with unevenly distributed perfusion on single photon emission tomography are documented.