Session Information
Date: Wednesday, June 22, 2016
Session Title: Neuroimaging (non-PD)
Session Time: 12:00pm-1:30pm
Location: Exhibit Hall located in Hall B, Level 2
Objective: To compare (1) the echogenicity of substantia nigra (SN) in subjects with idiopathic REM behavior disorder (iRBD) and healthy controls and (2) to determine the correlation between 123-I Ioflupane SPECT (DaTSCAN) striatal binding indexes (SBI) and quantitative echogenicity indexes of SN (SEI) calculated by automatic evaluation software.
Background: Hyperechogenicity of the substantia nigra (SN) and decreased 123-I Ioflupane striatal binding are known as biomarkers of neurodegeneration. They may be helpful in predicting early conversion to manifest neurodegenerative phenotype. It is not clear whether these biomarkers reflect the same neuropathological processes. SN hyperechogenicity supposedly reflects microstructural SN tissue changes while SBI is considered as marker of presynaptic striatal neuronal loss.
Methods: Fifty subjects (47M/3F, mean age 65.8±(SD)8.9) with iRBD confirmed according to The American Academy of Sleep Medicine Manual (AASM, 2007) were examined with a battery of tests including the Movement Disorders Society Unified PD Rating Scale (MDS-UPDRS) and transcranial sonography (TCS). TCS was performed in 18 control subjects (17M/1F, mean age 49,22±(SD)9.8). SN echogenicity was assessed by i) manual measurement and by ii) in-house developed automatic evaluation software that calculates quantitative SEI. Higher SEI from both sides was used for comparison with the control group. DaTSCAN examination was performed in 31/50 patients and correlations between bilateral SBI and SEI were calculated.
Results: The mean MDS-UPDRS-III score in iRBD subjects was 2±6. At least unilateral SN hyperechogenicity (area>0.20 cm2 by manual measurement) was found in 9 (20.6%) iRBD subjects. The mean SEI in iRBD (28.7±14.9) was not significantly different from the control group (23.9±8.4) (p=0.21). SBI was abnormal in 16 (51.6%) iRBD subjects. Both, SN hyperechogenicity and abnormal SEI were detected in 4 subjects. SEI did not correlate with SBI.
Conclusions: Quantitative assessment of SN echogenicity showed no difference between iRBD subjects and controls indicating that SN neurodegeneration in iRBD is not associated with its increased echogenicity. Additionally, we did not confirm the correlation between SEI and 123-I Ioflupane SBI suggesting that these biomarkers reflect different neuropathological processes in iRBD.
To cite this abstract in AMA style:
J. Mašková, P. Dušek, D. Školoudík, K. Kupka, K. Šonka, V. Ibarburu Lorenzo Y Losada, J. Kubinyi, E. Ruzicka. Comparative study of the substantia nigra echogenicity and 123-I ioflupane SPECT in patients with REM behavior disorder [abstract]. Mov Disord. 2016; 31 (suppl 2). https://www.mdsabstracts.org/abstract/comparative-study-of-the-substantia-nigra-echogenicity-and-123-i-ioflupane-spect-in-patients-with-rem-behavior-disorder/. Accessed June 15, 2025.« Back to 2016 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/comparative-study-of-the-substantia-nigra-echogenicity-and-123-i-ioflupane-spect-in-patients-with-rem-behavior-disorder/