Abstract
Aim: to assess the prevalence of incidental basal ganglia calcifications among patients having a brain computed tomography scan done for other non-related causes.
Methods: all brain computed tomography scan performed at Princess Basma Hospital between Feb-July 2006 were retrospectively reviewed and interpreted by the same neuro-radiologist. The cohort was divided into two groups according to gender and three groups according to age group every 20 years. The results were compared among groups using Epinfo 6. Blood was withdrawn only for those with brain calcifications for complete blood count, kidney function tests, calcium profile, vitamin D level and Parathyroid hormone.
Results: A total of 1040 computed tomography scans were eligible for this study (552 males). The overall prevalence of basal ganglia calcifications was 1.25 %.{ 0.72% for males vs.1.85% for females; Odds Ratio = 2.57 (0.72-9.98). Relative Risk = 2.55 (0.79-8.21), p=0.1). The prevalence increased with increasing age being 0.6% in younger age group vs. 2.4% in those above 60 years. Biochemical lab results were normal in all except of elevated Parathyroid hormone in 6 patients of whom only one was proved to have low vitamin D3 level.
Conclusion: The prevalence of basal ganglia calcifications is quite low in this cohort and shows a steep increase with increasing age. High parathyroid hormone is one of the important biochemical abnormalities that warrant further evaluation and investigation in a large cross sectional cohort to identify direct cause-effect relationship.

Key words: Prevalence, basal ganglia, calcification, brain CT scan, hyperparthyroidism