Anja Flamez1, Wietse Wiels2, Peter Van Schuerbeek3, Johan De Mey3, Jacques De Keyser4, Chris Baeken5. 1. Department of Neurology, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels, Belgium. Electronic address: anja.flamez@uzbrussel.be. 2. Department of Neurology, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels, Belgium. 3. Department of Radiology, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels, Belgium. 4. Department of Neurology, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels, Belgium; Department of Neurology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700 Groningen, the Netherlands. 5. Department of Psychiatry, UZ Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels, Belgium; Ghent University, Department of Psychiatry and Medical Psychology, C. Heymanslaan 10, 9000 Ghent, Belgium; Ghent Experimental Psychiatry (GHEP) Lab, Ghent University, Ghent, Belgium.
Abstract
OBJECTIVE: To study the effect of Low Frequency repetitive Transcranial Magnetic Stimulation (LF rTMS) on brain metabolites in late stage Parkinson's disease (PD) patients (disease duration at least 4 years and Hoehn and Yahr (1969) score at least 2 in OFF). Several neuroimaging data support a role for pre-Supplementary Motor Area (pre-SMA) involvement in the pathogenesis of Parkinson's disease. Proton magnetic resonance spectroscopy (1H-MRS) measures in vivo metabolites, but results in PD brain remain conflicting and little is known of the effect of LF rTMS thereupon. METHODS: We investigate the neurochemical profile of the right pre-SMA in 17 late stage PD patients (11 male and 6 female, mean age of 71 years) before and after one session of sham controlled 1 Hz rTMS (1000 pulses, 16 minutes), focusing on the tNAA/tCr and tCho/tCr ratios. RESULTS: The tNAA/tCr ratio was unaffected by one session of LF rTMS. We did observe a significant effect of real LF rTMS on the tCho/tCr ratio, inversely correlated with disease duration, and not related to the presence of dyskinesias. As expected, one session of LF rTMS did not affect clinical outcome. CONCLUSIONS: LF rTMS at the right pre-SMA in late stage Parkinson's disease patients does not alter tNAA/tCr, but influences tCho/tCr ratio, in particular in patients with shorter disease duration. SIGNIFICANCE: Pre-SMA LF rTMS seems to influence membrane turnover, more importantly in patients with shorter disease duration. Larger LF rTMS treatment studies applying multiple sessions are needed.
OBJECTIVE: To study the effect of Low Frequency repetitive Transcranial Magnetic Stimulation (LF rTMS) on brain metabolites in late stage Parkinson's disease (PD) patients (disease duration at least 4 years and Hoehn and Yahr (1969) score at least 2 in OFF). Several neuroimaging data support a role for pre-Supplementary Motor Area (pre-SMA) involvement in the pathogenesis of Parkinson's disease. Proton magnetic resonance spectroscopy (1H-MRS) measures in vivo metabolites, but results in PD brain remain conflicting and little is known of the effect of LF rTMS thereupon. METHODS: We investigate the neurochemical profile of the right pre-SMA in 17 late stage PDpatients (11 male and 6 female, mean age of 71 years) before and after one session of sham controlled 1 Hz rTMS (1000 pulses, 16 minutes), focusing on the tNAA/tCr and tCho/tCr ratios. RESULTS: The tNAA/tCr ratio was unaffected by one session of LF rTMS. We did observe a significant effect of real LF rTMS on the tCho/tCr ratio, inversely correlated with disease duration, and not related to the presence of dyskinesias. As expected, one session of LF rTMS did not affect clinical outcome. CONCLUSIONS: LF rTMS at the right pre-SMA in late stage Parkinson's diseasepatients does not alter tNAA/tCr, but influences tCho/tCr ratio, in particular in patients with shorter disease duration. SIGNIFICANCE: Pre-SMA LF rTMS seems to influence membrane turnover, more importantly in patients with shorter disease duration. Larger LF rTMS treatment studies applying multiple sessions are needed.