[Familial idiopathic striato-pallido-dentate calcifications: clinical and brain imaging study in a family].

Familial idiopathic basal ganglia calcification (FIBGC) is a rare condition and its pathophysiology has not so far been elucidated. We report the results of a clinical study in two patients of a family affected with FIBGC. Brain imaging with 18-FDG-PET was performed in one. Psychiatric and cognitive troubles were the main clinical symptoms. Basal ganglia calcifications were associated with white matter lesions. The PET study performed in one patient revealed a striatal and a posterior cingulate hypometabolism. Posterior cingulate gyrus is involved in episodic memory processing, and could be involved in episodic memory deficit observed in this patient. These results suggest that a cortical dysfunction could be associated to the disease. The underlying mechanism, that could be a neuronal loss, a cortical deafferentation or an alteration of synaptic transmission, remains to be elucidated.