Desynchronization of temporal lobe theta-band activity during effective anterior thalamus deep brain stimulation in epilepsy.
BACKGROUND: Bilateral cyclic high frequency deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) reduces the seizure count in a subset of patients with epilepsy. Detecting stimulation-induced alterations of pathological brain networks may help to unravel the underlying physiological mechanisms related to effective stimulation delivery and optimize target engagement.
METHODS: We acquired 64-channel electroencephalography during ten ANT-DBS cycles (145Hz, 90μs, 3-5V) of 1-minute ON followed by 5-minutes OFF stimulation to detect changes in cortical activity related to seizure reduction. The study included 14 subjects (three responders, four non-responders, and seven healthy controls). Mixed-model ANOVA tests were used to compare differences in cortical activity between subgroups both ON and OFF stimulation, while investigating frequency-specific effects for the seizure onset zones.
RESULTS: ANT-DBS had a widespread desynchronization effect on cortical theta and alpha band activity in responders, but not in non-responders. Time domain analysis showed that the stimulation induced reduction in theta-band activity was temporally linked to the stimulation period. Moreover, stimulation induced theta-band desynchronization in the temporal lobe channels correlated significantly with the therapeutic response. Responders to ANT-DBS and healthy-controls had an overall lower level of theta-band activity compared to non-responders.
CONCLUSION: This study demonstrated that temporal lobe channel theta-band desynchronization may be a predictive physiological hallmark of therapeutic response to ANT-DBS and may be used to improve the functional precision of this intervention by verifying implantation sites, calibrating stimulation contacts, and possibly identifying treatment responders prior to implantation.
PMID: 32445879 [PubMed – as supplied by publisher]
Neuroimage. 2020 May 20;:116967
Authors: Scherer M, Milosevic L, Guggenberger R, Maus V, Naros G, Grimm F, Bucurenciu I, Steinhoff BJ, Weber YG, Lerche H, Weiss D, Rona S, Gharabaghi A