Room: Exhibit Hall | Forum 8
Purpose: The aim of this study was to identify changes in iron deposition in Essential Tremor (ET) by Magnetic Resonance Imaging (MRI) T2* mapping, using the same study in Parkinsonâ€™s disease (PD) for positive control.
Methods: MRI T2* images were acquired in two separate studies on 21 ET cases and 27 matched controls, as well as on 10 PD cases and 7 controls. Both studies were performed on a Siemens 3T scanner with similar protocols. T2* maps were calculated directly on the Siemens scanners. Analysis of both studies was performed by the same individual, using the same methods. Manual regions of interest (ROIs) were drawn to encompass the substantia nigra (SN) and the globus pallidus (GP) using MRIcron to obtain average T2* values per ROI. Separate group comparisons were performed with a linear regression in R using age and sex as covariates.
Results: A statistically significant decrease in T2* value was found between PD cases and their respective control group in the right SN (p = 0.003), indicating increased iron deposition in that region. No statistically significant difference in the SN was found between ET cases and their respective control group. No statistically significant differences were found in the GP in either group.
Conclusion: Increased iron deposition is well documented in PD and has been suggested as a marker of disease progression. It also has been discussed as a marker of cellular damage and oxidative stress in neurodegenerative diseases, giving rise to the hypothesis that brain iron might also be elevated in ET. In this study we demonstrate no increase in iron deposition in ET, using a method that detected changes in PD patients. The lack of increased iron deposition could serve as an important biomarker in defining the differences and similarities in pathophysiology between these two common movement disorders.
Funding Support, Disclosures, and Conflict of Interest: Funding:NINDS 5R01NS085136, APVV15/0253, VEGA2/0191/15, SAS/NSC Joint Research Grant 2013/17. E.D.L. has received research grants from the NINDS. U.D. has received research grants from the NIEHS. J.U. has received research grants from APVV, VEGAE, and SAS/NSC. E.C., K.O., J.P.D., and W.B. have no conflicts to report.