Table 4.
LF rTMS over the SMA
| Study | Study design | Baseline scores and definition of response | rTMS-protocol parameters | Results | Duration of follow up and results | Limitations |
|---|---|---|---|---|---|---|
| Mantovani et al60 | 21 patients, (9 active rTMS, 9 sham rTMS); 4-week RCT and 4-week open-label; age, active 39.7±8.6 years, sham, 39.4±10.2 years; duration of illness, active 22.4±13.8 years, sham 22.1±7.3 years | YBOCS, active 26±5.4, sham 26.7±5.5; response definition, patients with 25% YBOCS reduction at the end of phase 1 | 8 weeks; 1 Hz; SMA; figure-eight coil; mapping via international 10–20 EEG system; phase 1, active vs sham rTMS 4 weeks, 5 days/week; 20-minute train/session; 1,200 pulses/day; 100% RMT; phase 2, 4-week open-label rTMS to nonresponders to sham and responders and nonresponders to active rTMS in phase 1 | NS response rate between active and sham groups at week 2 and week 4 (P=0.294, P=0.153); at 4 weeks, active vs sham YBOCS NS; active vs sham YBOCS SR P=0.031 | 8 weeks; phase 2; control vs active, significant effect of time on YBOCS (P=0.000); sham vs active, NS YBOCS change; at 3 months, six responders to active rTMS showed a 51% decrease from baseline YBOCS | Small sample, “imperfect” sham system, potential synergistic effect with medication |
| Gomes et al62 | 22 patients; double-blind RCT; active rTMS 12, sham rTMS 10; mean age, active 35.5±7.5 years + duration of illness 17±8 years; sham, age 37.5±16 years; duration of illness 19.5±12 years | Active YBOCS 36.4±3.2, sham YBOCS 31.8±3.5; responders, patients with 25% YBOCS reduction | 2 weeks; 1 Hz; 5 days a week; 20-minute trains; 1,200 pulses/day; figure-eight coil; 100% RMT; bilateral pre-SMA localized via international 10–20 EEG system | Week 2, significant reduction in YBOCS between active and sham (P=0.0076); response rate, active vs sham P<0.001 | 14 weeks; YBOCS active vs sham P<0.0001; response rate, active vs sham P<0.001 | Small sample, limitations in sham design, synergy with medications, manual navigation system |
| Arumugham et al63 | 34 treatment-refractory OCD patients; active vs sham rTMS; RCT; baseline demographic data not reported | Baseline data not reported; definition of response NA | 3 weeks, 18 days; 1 Hz; 1,200 pulses/day; pre-SMA; process of targeting NA; coil description NA | Week 3, NS difference between active and sham rTMS (P=0.972) | 12 weeks – results NA | Description of sham rTMS NA, stimulation protocol and duration of pulse intervals NA |
| Hawken et al64 | 22 patients; multicenter double- blind RCT; age, active 33±11 years, sham 34±14 years; duration of illness, center B vs center T, P=0.037 | Center B, YBOCS 28±5; center T, YBOCS 28±4; responders, YBOCS reduction >25% | 6 weeks; 1 Hz; 5 days a week for 4 weeks, then 3 days a week for 1 week and 2 days a week for 1 week 20-minute sessions (5-minute trains and 2-minute intertrain intervals); figure-eight coil; 110% RMT; bilateral SMA localized via international 10–20 EEG system; active tilted coil 90° from the skull; 110% RMT | Significant effect; after 5 weeks (25 treatments), YBOCS active vs sham P=0.023 | 8 weeks; significant effect; 2 weeks after last treatment, YBOCS active vs sham P=0.044 | Small sample, potential blinding issue with sham treatment due to imperfect sham design, multicenter design with significant difference in the duration of illness between sites |
| Pelissolo et al65 | 36 patients with YBOCS >15, >2 years of illness and 8 weeks of nonresponse to two SSRIs; 75% with comorbid MDD; age 41.5±10.7 years; duration of illness, active 19.8±12.8 years, sham 24±10.9 years | YBOCS, active 30.2±4.2, sham 28.6±4.6; unclear definition of responders | 4 weeks; 1 Hz; 26-minute sessions; 4/5-minute trains with 2-minute rest; 1,500 pulses/day; figure-eight coil; 100% RMT; bilateral pre-SMA; T1 MRI neuronavigation; sham rTMS, Magstim sham coil | NS differences between active and sham at week 4 | NS difference over 12 weeks | Comorbidity with depressive symptoms |
Abbreviations: LF, low-frequency; rTMS, repetitive transcranial magnetic stimulation; SMA, supplementary motor area; RCT, randomized controlled trial; YBOCS, Yale–Brown Obsessive–Compulsive Scale; EEG, electroencephalography; RMT, resting motor threshold; NS, nonsignificant; SR, self-report; OCD, obsessive–compulsive disorder; NA, not available; SSRIs, selective serotonin-reuptake inhibitors; MDD, major depressive disorder; MRI, magnetic resonance imaging.