Quantifying brain iron deposition in patients with Parkinson's disease using quantitative susceptibility mapping, R2 and R2

Purpose: To evaluate the sensitivity and specificity of quantitative magnetic resonance (MR) iron mapping including R2, R2* and magnetic susceptibility to differentiate patients with Parkinson's disease (PD) from healthy controls. Materials and Methods: Thirty (30) healthy controls (HC) (64 +/- 7 years old) and 20 patients with idiopathic PD (66 +/- 8 years old) were studied using a 3 T MR imaging scanner. R2 maps were generated from GRASE sequence while R2*, and quantitative susceptibility mapping (QSM) were obtained from a conventional multi-echo gradient-echo sequence. R2, R2* and relative susceptibility (4) values of structures in the basal ganglia were measured for each patient and control. An analysis of sensitivity and specificity and unpaired t-test was applied to the two groups. Results: A significant difference (p < 0.05) was found for R2 and Delta x values in the substantia nigra as a whole and in the pars compacta for PD patients. The R2* values were different significantly (p < 0.05) only on the substantia nigra pars compacta. QSM presented the highest sensitivity and specificity to differentiate the two populations. Conclusion: The QSM map was the most sensitive quantitative technique for detecting a significant increase of iron for PD. The highest significant difference between controls and patients was found in the substantia nigra pars compacta using QSM. (C) 2015 Elsevier Inc. All rights reserved.