Pathological studies of the basal ganglia calcification observed on CT scan

A pathological study was performed on the basal ganglia calcification observed at the CT scan of a 76-year-old female with multiple cerebral infarction. However, she showed no extrapyramidal sign or hypopara-thyroidism. The pathological changes in the basal ganglia were the deposition of a basophilic mass on the walls of the arterioles and capillaries as well as in the cerebral parenchym of the globus pallidus. An histochemically Ca positive reaction was observed by the use of Kossa's stain and an electron-probe microanalysis revealed Ca-K..cap alpha.. in the wall of the arterioles. An electron-microscopic picture of the deposit showed a collection of concentric structures of electron-dense and electron-light layers with cores. Such a structure was very similar to the pseudocalcium of the globus pallidus, a frequent finding in aged brains. Upon the use of Kossa's stain, the pseudocalcium shows a Ca reaction in 9.9% of pseudocalcium-positive cases in the aged. In conclusion, a main cause of basal ganglia calcification in CT in elderly persons is the deposition in the so-called pseudocalcium of a large amount of calcium in the globus pallidus.