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rTMS in depression - accelerating response to therapy
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Abstracts / Brain Stimulation 10 (2017) 346e540
Introduction: Theta burst stimulation (TBS) can alter cortical excitability, similar to standard repetitive transcranial magnetic stimulation paradigms, with a major advantage of shorter stimulation duration at a lower intensity. There is increasing interest in the use of TBS as a therapeutic tool for disorders such as depression and schizophrenia, where prefrontal cortex is the primary target for treatment. In developing clinical applications for such psychiatric illnesses, there is a need to explore effects of different parameters of TBS in this region. This study aimed to examine the effects of different intensities of intermittent TBS (iTBS) on cortical reactivity in the prefrontal cortex. We hypothesized that iTBS would show greater cortical effects at sub-threshold intensities. Methods: 16 healthy participants received iTBS over prefrontal cortex (F1 electrode) at either 50, 75 or 100% rMT in separate sessions. Single pulse TMS-EEG was used to assess change in cortical reactivity via TMS-evoked potentials and TMS-evoked oscillations before and after iTBS. Results: Cluster-based statistics revealed a significant increase in N100 amplitude following 50% (p ¼ 0.011) and 75% (p ¼ 0.010) iTBS over prefrontal regions. No significant change was observed with 100% iTBS. Between conditions, the iTBS-induced change in N100 was larger following 75% compared to 100% iTBS (p ¼ 0.008). For oscillations, change in TMSevoked theta (p ¼ 0.027) and gamma power (p ¼ 0.006) were larger following 75% compared to 100% iTBS (figure below). No significant differences were observed between 50% and 75% iTBS, or 50% and 100% iTBS.
Ă
Discussion: Intensity of the stimulation should be carefully considered when administering TBS in the prefrontal cortex, as it may reduce iTBSinduced changes in cortical reactivity at or above individual’s motor threshold. This study may aid in optimising stimulation paradigm prior to the conduct of clinical trials. Keywords: theta burst stimulation (TBS), TMS-EEG, prefrontal cortex, intensity
[0233] RTMS IN DEPRESSION - ACCELERATING RESPONSE TO THERAPY P.B. Fitzgerald*. Monash University, Australia Purpose: Repetitive transcranial magnetic stimulation (rTMS) is now a well-established new treatment modality for patients with depressive disorders that has been assessed across a large range of controlled studies. However, response to treatment is typically slow and standard courses require 4 to 6 weeks of treatment sessions conducted five days per week, a practical burden for many patients. There is increasing interest in the development of high dose and accelerated treatment protocols although few studies to date have compared accelerated and standard methods of TMS administration. Methods: We have conducted a randomised controlled trial comparing a standard daily rTMS course over four weeks to an accelerated course of TMS treatment involving the same overall dose of therapy applied during three days in week one, two days in week two and one day week three. Results: No difference in treatment outcome was found between accelerated and the standard forms of rTMS treatment. There was a slightly higher dropout rate in the accelerated group but no marked difference in overall treatment tolerability. Anecdotally, accelerated treatment was extremely popular with patients.
Conclusions: There is emerging evidence that rTMS for patients with depression can be successfully applied in novel schedules over shorter periods of time. Accelerated treatment approaches have potential to make access to TMS more flexible and practical for some patients Keywords: depression, rTMS, accelerated, trial
[0234] DIFFERENT ROLES OF PRE-SMA AND SMA IN HUMAN VISUOMOTOR SEQUENCE LEARNING: A TMS STUDY T. Shimizu*1, 2, R. Hanajima 1, R. Tsutsumi 1, Y. Shirota 2, N. Tanaka 2, M. Hamada 2, Y. Ugawa 3. 1 Kitasato Medical University, Japan; 2 University of Tokyo, Japan; 3 Fukushima Medical University, Japan Introduction: Both the pre-supplementary motor area (pre-SMA) and the supplementary motor area proper (SMA) are known to take part in the visuomotor sequence learning. Previous reports implicated that the preSMA plays a role especially in the acquisition of a new sequence, while the SMA in movement itself rather than learning. Here we studied the roles of pre-SMA or SMA in human visuomotor sequence learning with repetitive transcranial magnetic stimulation technique. Methods: Sixteen healthy volunteers participated in this experiment. We applied Quadripulse transcranial magnetic stimulation (QPS) or sham stimulation over the left pre-SMA or SMA for 30 minutes. QPS consisted of repeated bursts of four monophasic TMS pulses separated by inter-stimulus intervals of 5 ms (QPS-5) or 50 ms (QPS-50) with an inter-burst interval of 5 s. After QPS, each subject performed the 210 task, which is similar to the visuomotor sequential task reported by Hikosaka et al. For performance evaluation, we counted the number of errors to assess the performance accuracy, and measured the movement time (MT) and button press reaction time (BP-RT) and obtained their acceleration, to assess the performance speed. Results: The number of errors was larger after QPS-5 over the pre-SMA compared to sham stimulation, whereas it did not differ between QPS-50 and sham conditions. In contrast, the number of errors did not differ between any stimulus conditions in SMA stimulation. Acceleration of BP-RT was enhanced after QPS-50 over the SMA and inhibited after QPS-5 over the SMA. In contrast, acceleration of BP-RT did not differ between any stimulus conditions in the pre-SMA stimulation. Discussion: Our findings suggested that the pre-SMA plays an important role in the acquisition of visuomotor sequence, whereas the SMA plays an important role in automatization of sequential movements. Keywords: transcranial magnetic stimulation, Quadripulse stimulation, sequence learning, supplementary motor area [0235] CLINICAL BENEFITS OF ELECTROCONVULSIVE THERAPY FOR DEPRESSED PATIENTS WITH REFRACTORY COMPLEX REGIONAL PAIN SYNDROME (CRPS) TYPE 1: A PRELIMINARY RESULT T.S. Kim*, H.J. Park, Y.H. Kim, D.E. Moon. The Catholic University of Korea, Republic of Korea Background: Complex regional pain syndrome (CRPS) is a chronic condition that has spontaneous severe pain and hyperesthesia of one or more parts of legs and arms, which is accompanied with problems of the automatic nervous system or the motor nervous system. It is often treatment-refractory and is frequently accompanied by depressive disorder. Electroconvulsive therapy (ECT) is a well-established treatment option for treatment-resistant depression and has also been applied in the treatment of chronic pain. In this open study, we investigated the efficacy of ECT in refractory depressed patient with CRPS type 1. Methods: Eight depressed patients (M¼4; F¼4) presenting CRPS type 1, who were treatment-refractory though treated with the best medical and psychiatric medication, were participated and had a total of 8 sessions of ECT three times a week. Pain intensity was assessed using Visual Analogue Scale (VAS) at baseline and endpoint (4 weeks) and after each session. Hamilton Depression Rating Scale (HDRS), Beck Scale for Suicide Ideation (SSI), Insomnia Severity Index (ISI), and Euro-QoL-5D (EQ-5D) were respectively measured for depression, suicide, insomnia, and quality of life at baseline and endpoint.
Abstracts / Brain Stimulation 10 (2017) 346e540
Introduction: Theta burst stimulation (TBS) can alter cortical excitability, similar to standard repetitive transcranial magnetic stimulation paradigms, with a major advantage of shorter stimulation duration at a lower intensity. There is increasing interest in the use of TBS as a therapeutic tool for disorders such as depression and schizophrenia, where prefrontal cortex is the primary target for treatment. In developing clinical applications for such psychiatric illnesses, there is a need to explore effects of different parameters of TBS in this region. This study aimed to examine the effects of different intensities of intermittent TBS (iTBS) on cortical reactivity in the prefrontal cortex. We hypothesized that iTBS would show greater cortical effects at sub-threshold intensities. Methods: 16 healthy participants received iTBS over prefrontal cortex (F1 electrode) at either 50, 75 or 100% rMT in separate sessions. Single pulse TMS-EEG was used to assess change in cortical reactivity via TMS-evoked potentials and TMS-evoked oscillations before and after iTBS. Results: Cluster-based statistics revealed a significant increase in N100 amplitude following 50% (p ¼ 0.011) and 75% (p ¼ 0.010) iTBS over prefrontal regions. No significant change was observed with 100% iTBS. Between conditions, the iTBS-induced change in N100 was larger following 75% compared to 100% iTBS (p ¼ 0.008). For oscillations, change in TMSevoked theta (p ¼ 0.027) and gamma power (p ¼ 0.006) were larger following 75% compared to 100% iTBS (figure below). No significant differences were observed between 50% and 75% iTBS, or 50% and 100% iTBS.
Ă
Discussion: Intensity of the stimulation should be carefully considered when administering TBS in the prefrontal cortex, as it may reduce iTBSinduced changes in cortical reactivity at or above individual’s motor threshold. This study may aid in optimising stimulation paradigm prior to the conduct of clinical trials. Keywords: theta burst stimulation (TBS), TMS-EEG, prefrontal cortex, intensity
[0233] RTMS IN DEPRESSION - ACCELERATING RESPONSE TO THERAPY P.B. Fitzgerald*. Monash University, Australia Purpose: Repetitive transcranial magnetic stimulation (rTMS) is now a well-established new treatment modality for patients with depressive disorders that has been assessed across a large range of controlled studies. However, response to treatment is typically slow and standard courses require 4 to 6 weeks of treatment sessions conducted five days per week, a practical burden for many patients. There is increasing interest in the development of high dose and accelerated treatment protocols although few studies to date have compared accelerated and standard methods of TMS administration. Methods: We have conducted a randomised controlled trial comparing a standard daily rTMS course over four weeks to an accelerated course of TMS treatment involving the same overall dose of therapy applied during three days in week one, two days in week two and one day week three. Results: No difference in treatment outcome was found between accelerated and the standard forms of rTMS treatment. There was a slightly higher dropout rate in the accelerated group but no marked difference in overall treatment tolerability. Anecdotally, accelerated treatment was extremely popular with patients.
Conclusions: There is emerging evidence that rTMS for patients with depression can be successfully applied in novel schedules over shorter periods of time. Accelerated treatment approaches have potential to make access to TMS more flexible and practical for some patients Keywords: depression, rTMS, accelerated, trial
[0234] DIFFERENT ROLES OF PRE-SMA AND SMA IN HUMAN VISUOMOTOR SEQUENCE LEARNING: A TMS STUDY T. Shimizu*1, 2, R. Hanajima 1, R. Tsutsumi 1, Y. Shirota 2, N. Tanaka 2, M. Hamada 2, Y. Ugawa 3. 1 Kitasato Medical University, Japan; 2 University of Tokyo, Japan; 3 Fukushima Medical University, Japan Introduction: Both the pre-supplementary motor area (pre-SMA) and the supplementary motor area proper (SMA) are known to take part in the visuomotor sequence learning. Previous reports implicated that the preSMA plays a role especially in the acquisition of a new sequence, while the SMA in movement itself rather than learning. Here we studied the roles of pre-SMA or SMA in human visuomotor sequence learning with repetitive transcranial magnetic stimulation technique. Methods: Sixteen healthy volunteers participated in this experiment. We applied Quadripulse transcranial magnetic stimulation (QPS) or sham stimulation over the left pre-SMA or SMA for 30 minutes. QPS consisted of repeated bursts of four monophasic TMS pulses separated by inter-stimulus intervals of 5 ms (QPS-5) or 50 ms (QPS-50) with an inter-burst interval of 5 s. After QPS, each subject performed the 210 task, which is similar to the visuomotor sequential task reported by Hikosaka et al. For performance evaluation, we counted the number of errors to assess the performance accuracy, and measured the movement time (MT) and button press reaction time (BP-RT) and obtained their acceleration, to assess the performance speed. Results: The number of errors was larger after QPS-5 over the pre-SMA compared to sham stimulation, whereas it did not differ between QPS-50 and sham conditions. In contrast, the number of errors did not differ between any stimulus conditions in SMA stimulation. Acceleration of BP-RT was enhanced after QPS-50 over the SMA and inhibited after QPS-5 over the SMA. In contrast, acceleration of BP-RT did not differ between any stimulus conditions in the pre-SMA stimulation. Discussion: Our findings suggested that the pre-SMA plays an important role in the acquisition of visuomotor sequence, whereas the SMA plays an important role in automatization of sequential movements. Keywords: transcranial magnetic stimulation, Quadripulse stimulation, sequence learning, supplementary motor area [0235] CLINICAL BENEFITS OF ELECTROCONVULSIVE THERAPY FOR DEPRESSED PATIENTS WITH REFRACTORY COMPLEX REGIONAL PAIN SYNDROME (CRPS) TYPE 1: A PRELIMINARY RESULT T.S. Kim*, H.J. Park, Y.H. Kim, D.E. Moon. The Catholic University of Korea, Republic of Korea Background: Complex regional pain syndrome (CRPS) is a chronic condition that has spontaneous severe pain and hyperesthesia of one or more parts of legs and arms, which is accompanied with problems of the automatic nervous system or the motor nervous system. It is often treatment-refractory and is frequently accompanied by depressive disorder. Electroconvulsive therapy (ECT) is a well-established treatment option for treatment-resistant depression and has also been applied in the treatment of chronic pain. In this open study, we investigated the efficacy of ECT in refractory depressed patient with CRPS type 1. Methods: Eight depressed patients (M¼4; F¼4) presenting CRPS type 1, who were treatment-refractory though treated with the best medical and psychiatric medication, were participated and had a total of 8 sessions of ECT three times a week. Pain intensity was assessed using Visual Analogue Scale (VAS) at baseline and endpoint (4 weeks) and after each session. Hamilton Depression Rating Scale (HDRS), Beck Scale for Suicide Ideation (SSI), Insomnia Severity Index (ISI), and Euro-QoL-5D (EQ-5D) were respectively measured for depression, suicide, insomnia, and quality of life at baseline and endpoint.