Basal Ganglia: Physiologic Calcifications

Abstract

Basal ganglia (BG) calcifications are a common cause of either confusion or misinterpretation, particularly when the degree of calcification is only mild or unilateral. In general, although there is no landmark recent literature regarding the incidence of idiopathic, incidence BG calcifications on CT, the incidence is thought to be less than 2 % in the overall population and has been shown to increase with age. Such calcifications should not be present in pediatric patients in under 13–15 years of age (based on scant literature, anecdotal reports, and this author’s experience). Notably, for the purposes of this section, the term BG refers to the traditional definition of those nuclei involved in voluntary motor initiation consisting of the globi pallidi (GP), caudate nuclei (CN), as well as the substantia nigra (SN) and the subthalamic nuclei (STN). Also, it is important to point out that physiologic calcifications in the SN and the STN are much less common than in the other nuclei. Additionally, the dentate nuclei (DN) are one of the three sets of paired deep nuclei of the cerebellum, and physiologic calcifications are also not uncommon in this location in the elderly.