Table 2.
Inspection of EEG for epileptiform abnormalities during or after repetitive TMS in patients and healthy subjects. Consensus has been reached for this table.
| Authors | Subjects | TMS-parameters | EEG-measures | Timing of EEG | Findings with potential safety concern | Duration of after-effects |
|---|---|---|---|---|---|---|
| Loo et al., 2001 | N = 18 Depression | 10 days of 10 Hz/30 × 5 s train: 25 s ITI DLPFC/110%MT | visual inspection waking EEG | before and after TMS | Yes: Minor, potentially epileptiform abnormalities in 1 patient (in the absence of seizure) | not assessed |
| Boutros et al., 2001 | N = 5 Depression | max 10 days of 5–20 Hz/max 20 × 2 s: 58 s ITI DLPFC/80–100%MT | visual inspection waking EEG | before and during TMS | No: despite EEG-abnormalities at baseline: no change | |
| Boutros et al. (2000) | N = 14 Depression | 10 days of 20 Hz/20 × 2 s train: 58 s ITI DLPFC/80%MT | visual inspection waking EEG | before, during and after TMS | Yes: 1 case with rare slow-wave transients online to TMS | no after-effects |
| N = 7 Schizophrenia | 4 sessions of 1 Hz/4:6:12:16 min temporal cortex | visual inspection waking EEG | before, during and after tTMS | No (no change) | no after-effects | |
| N = 5 OCD | 5 days of 20 Hz/30 × 2 s train: 58 s ITI DLPFC/80%MT | visual inspection waking EEG | before, during and after TMS | Yes: 1 case with increased theta activity during TMS | no after-effects | |
| Fregni et al., 2006 | N = 15 Stroke | 5 days of 1 Hz/20 min Unaffected hemisphere/100%MT | visual inspection waking EEG | online and 2 h after treatment | No (no change) | no after-effects |
| Cantello et al., 2007 | N = 43 Epilepsy | 5 days of 0.3 Hz/55.5 min vertex/100%rMT | visual inspection waking EEG Semi-quantitative | before and after TMS | No: decrease in interictal spikes in 1/3 of patients | |
| Joo et al., 2007 | N = 35 Epilepsy | 5 days of 0.5 Hz/50-100 min focus or vertex/100%rMT | visual inspection waking EEG | before and after treatment | No: decrease in interictal spikes | not assessed |
| Conte et al., 2007 | N = 1 Epilepsy | different sessions of 5 Hz/2 s trains vertex/120%MT | duration of spike and waves | online to TMS | No: decrease in duration of discharges | no after-effect |
| Fregni et al., 2006 | N = 21 Epilepsy | 5 days of 1 Hz/20 min foucs/70% max | visual inspection waking EEG | before and after TMS | No: decrease in epileptiform discharges | up to 30 days washed out at 60 days |
| Fregni et al., 2005 | N = 8 Epilepsy | 1 session of 0.5 Hz/20 min Focus/65% max | visual inspection waking EEG | before and after treatment | No: decrease in epileptiform discharges | at least 30 days |
| Misawa et al., 2005 | N = 1 Epilepsy | 1 session of 0.5 Hz/3.3 min focus/90%MT | visual inspection waking EEG | during TMS | No: significant change in EEG with epilepsy abolishment | 2 month |
| Rossi et al., 2004 | N = 1 Epilepsy | 1 session of 1 Hz/10 min focus/90%rMT | Spike averaging | before and after TMS | No: reduction in spike amplitude | not assessed |
| Menkes and Gruenthal, 2000 | N = 1 Epilepsy | 4 × 2 days of 0.5 Hz/3.3 min focus/95%MT | visual inspection waking EEG | before and after TMS | No: reduction in interictal spikes | not assessed |
| Schulze-Bonhage et al., 1999 | N = 21 Epilepsy | 4 stimuli at 20/50//100/500 Hz M1/120–150%MT | visual inspection waking EEG | during TMS | No: no case of after-discharges clearly assignable to TMS/interictal activity unchanged | no after-effects |
| Jennum et al., 1994 | N = 10 Epilepsy | 1 session of 30 Hz/8 × 1 s trains: 60 s ITI temporal and frontal/120%MT 50 Hz/2 × 1 s train: 60 s ITI frontal/120%MT | visual inspection waking EEG | before, during and after tTMS |
No: less epileptiform activity during TMS No: less epileptiform activity during TMS |
recovery after 10 min Recovery after 10 min |
| Steinhoff et al., 1993 | N = 19 Epilepsy | 0.3–0.1 Hz | visual inspection waking EEG | No: reduction of epileptic activity in some cases | ||
| Hufnagel and Elger (1991) | N = 48 Epilepsy | single or low frequency (<0.3 Hz) | visual inspection subdural electrodes | Yes/no: enhancement and suppression of epileptiform activity | na | |
| Dhuna et al., 1991 | N = 8 Epilepsy | 1 session of 8–25 Hz Various sites/intensities | visual inspection waking EEG |
No: 7 patients: no EEG changes Yes: 1 patient: seizure induction with 100% output intensity |
no after-effects | |
| Kanno et al., 2001 | N = 1 Patient | 1 session 0.25 Hz/2 × 3.3 min train DLPFC/110%MT | visual inspection waking EEG | during TMS | Yes: Potential epileptiform activity (focal slow-wave, no seizure) | no after-effects |
| Huber et al., 2007 | N = 10 healthy | 5 session of 5 Hz/6 × 10 s train: 5 s ITI M1/90%rMT | visual inspection waking EEG | during TMS | No (no abnormalities) | no after-effects |
| Jahanshahi et al., 1997 | N = 6 healthy | 2 sessions of 20 Hz/50 × 0.2 s: 3 s ITI M1/105–110%aMT | visual inspection waking EEG | before and after TMS | No (no abnormalities) | no after-effects |
| Wassermannn et al., 1996 | N = 10 healthy | 1 session of 1 Hz/max 5 min 6 scalp positions/125%rMT | visual inspection waking EEG | before and after TMS | No (no abnormalities) | no after-effects |
| N = 10 healthy | 1 session of 20 Hz/10 × 2 s train: 58 s ITI | visual inspection waking EEG | before and after TMS | No (no abnormalities) | no after-effects |