Background and purpose: Dot-like low intensity spots (a dot-like hemosiderin spot: dotHS) on T2*-weighted MR images (T2*WI), which is regarded as a sensitive method for hemosiderin detection, have been histologically diagnosed as old microbleeds associated with microangiopathies. The clinical significance of the dotHS, however, is still under debate. Therefore, we investigated the factors associated with dotHS.
Methods: We investigated 209 healthy volunteers in our hospital (sex: 106 males, 103 females; age: 38 to 78 years old, mean age: 56.4 +/- 8.3 years old) using "Brain Dock", a formalized screening system for asymptomatic brain diseases. The Odds ratio (OR) was estimated from multiple logistic regression analyses using the dotHS and variables.
Results: T2*WI demonstrated dotHS in 7.7% of volunteers, and the mean number of dotHS was 0.16 +/- 0.78. The hemosiderin was preferentially deposited in the basal ganglia and thalamus. Age > or = 65 years old (OR: 5.9; 95% confidence interval [CI]: 1.4-25.9; p = 0.02), hypertension (OR: 7.0; 95% CI: 1.4-34.7; p = 0.02), and headache (OR: 5.8; 95% CI: 1.4-24.6; p = 0.02) were all found to be independently associated with dotHS.
Conclusions: The dotHS was significantly associated with several factors, including age, hypertension and headache.