The use of MR-less MNI based neuronavigation for 10 Hz rTMS depression therapy: electrophysiological and clinical implications

Abstract

Repetitive transcranial magnetic stimulation (rTMS) is a popular and effective treatment for drug resistant depression. However, there is considerable variability in clinical outcomes, in previous studies and between patients. Because of high requirements for the use of fMRI based neuronavigation, many practitioners of rTMS still choose to use a standard 5 cm rule for rTMS coil placement which leads to large variations in which brain regions are being stimulated. We decided to test the possibilities of a MNI based MR-less neuronavigation system in rTMS depression treatment, by comparing the physiological effects and clinical outcomes of 3 distinct stimulation targets. Forty-six patients (thirty-three female, thirteen male) from the Republican Vilnius psychiatric hospital, all with drug resistant depressive disorder, participated in the study. All patients received high frequency (10 Hz) stimulation for 10 to 15 daily rTMS sessions. However, before the treatment they were randomly sorted into 3 groups according to stimulation target in MNI map: Group 1 received rTMS at point-40; 48; 35; Group 2 received rTMS at point-46; 45; 38; Group 3 received rTMS at point-38; 44; 26. Electroencephalography (EEG) recordings and clinical tests were obtained the day before the rTMS course and after the last session. There were some notable differences in physiological changes between the groups, with the largest EEG band spectral power increases found in Group 1 patients and the lowest in Group 2 patients. There was a significantly larger decrease of the Hamilton Depression Rating Scale (HAM-D) scores in the Group 3 (66.94%) compared to Group 1 (57.52%) and Group 2 (56.02%). This suggests it is possible to achieve higher clinical efficacy and less physiological impact on the brain when using different targets in a neuronavigated MNI based MR-less rTMS system.

Transcranial Magnetic Stimulation for Pain, Headache, and Comorbid Depression: INS-NANS Expert Consensus Panel Review and Recommendation

“…The need for this precision in clinical applications must be balanced against whether the use is feasible in any particular setting, and whether the application shows evidence that failure to use neuronavigation would lead to inadequate outcomes. Settings without access to an MRI could use a template brain that is adapted to individuals ; however, without a dedicated, trained staff, the technique is unfeasible. In the case of rTMS for chronic pain, the brain target with the most evidence for effectiveness is M1 contralateral to the side of pain .…”

Fronto-central resting-state 15-29Hz transient beta events change with therapeutic transcranial magnetic stimulation for posttraumatic stress disorder and major depressive disorder

“…Figure 3 presents power grand averages and standard error of the mean bars across all patients and EEG recording sessions (i.e., pre-and posttreatment). For each EEG sensor, peaks in activity consistently appear in delta/theta (1-6 Hz), alpha (7-14 Hz), and beta range (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29). As such, these bands defined the frequency boundaries for all further analyses.…”

“…The copyright holder for this preprint this version posted March 16, 2023. ; https://doi.org/10.1101/2023.03.11.23286902 doi: medRxiv preprint averaged local band power [16,17,18], event-related power and coherence [19,20], and for varied measures of time-domain signal complexity [21]. Recent studies applying machine learning showed that rTMS-induced changes in resting-state EEG coherences were predictive of clinical response in comorbid PTSD/MDD and able to distinguish active, sham, pre-treatment, and post-treatment groups [22,23].…”

“…Data analysis techniques applied to evaluate the impact of rTMS on EEG signals commonly rely on quantifying changes in the spectral domain, such as changes in regional oscillatory power and/or coherence among brain areas. Candidate EEG biomarkers to assess the effects of rTMS for depression have been proposed across several frequency bands (typically <40Hz), and for a range of spectral features, including averaged local band power [16,17,18], event-related power and coherence [19,20], and for varied measures of time-domain signal complexity [21]. Recent studies applying machine learning showed that rTMS-induced changes in resting-state EEG coherences were predictive of clinical response in comorbid PTSD/MDD and able to distinguish active, sham, pre-treatment, and post-treatment groups [22,23].…”

Neural temporal dynamics of negative emotional symptoms after iTBS in patients with stroke: a TMS-EEG study

“…Long-term paroxetine therapy was linked to an increase in Beta1 power in patients with major depression, according to post-medication EEG research, which suggested that Beta1 power was regulated by mood changes [40]. rTMS administered at 1 Hz over the right dorsolateral prefrontal lobe in depressed patients resulted in a marked increase in Beta oscillation [41]. An earlier investigation revealed that 1Hz-rTMS over the right DLPFC for treating depression led to a notable increase in Beta power.…”