Table 2.
Methodological details and results of the included studies
| Type of stimulator | Type of coil | Time of MEP evaluation | Number of repeats to be averaged for each state | Stimulus intensity | Coil placement | Target muscle | Predictive value for outcome after follow-up period | Electrophysiological measure | Ref no. |
|---|---|---|---|---|---|---|---|---|---|
| Magstim 200 stimulator | Figure-of-eight coil (7 cm diameter) | Within 48 h and after 6 months | Unclear | TMS intensity was initially set at maximal stimulator output (100%) | Tangentially to the scalp with the handle held backward | FDI and biceps brachii muscles | Yes (positively correlated with better scores on Barthel Index items reflecting bimanual coordination) | Latency, amplitude, and shape of ipsilateral responses | 11 |
| Magstim 200 stimulator (Magstim Ltd, Whitland, Dyfed, UK) | Figure-of-eight shaped coil (7 cm diameter) | Days 1 and 8 | 5 stimuli | Maximal output (100%) | The coil was placed tangentially to the scalp with the handle held backwards with a 30° downward tilt | FDI | Yes | MEP amplitude (MEP max/Mmax ratio) | 16 |
| Novametrix (Magstim model 200) | 9 cm diameter circular flat coil | 1–7 days, 30 days and 3 months after stroke | 4 stimuli | 80–100% | Flat on the vertex | ADM and tibialis anterior muscles | Yes | MEP amplitude, CMCT | 17 |
| Phasis (OTE Biomedica, Italy) and Neuro-MVP-4 (Neirosoft, Ivanovo, Russia) | No data available | During the first 3 days | At least 3 evoked responses | No data available | “projections of the motor zones of the cortex” (unclear) | APB | Yes | CMCT | 18 |
| Magstim Novametrix 200 magnetic stimulator | 9 cm diameter circular coil (Novametrix Inc) | Day 1 and after 1 year | 4 consecutive responses | Stimulation intensity was set at 100% of maximum stimulator output | “Standard” position | FDI | Yes | CMCT, latency and amplitude of MEPs | 9 |
| Magstim 200 magnetic stimulator | Circular coil of 9 cm in mean diameter | Days 1 and 14 | 4 consecutive responses | Stimulation intensity was 70% of maximal stimulator output or 100% if no response was obtained at 70% | Tangential plane above the vertex | FDI | Yes | CMCT, latency and amplitude of MEPs | 7 |
| Magstim 200 stimulator | Circular coil (outer diameter 12 cm) | Days 1–5 | 6 stimuli at the maximum stimulator output | 10% up to 100% of the stimulator output | Was centered over a point marked on the scalp at either C3 or C4 (International 10–20 System) with the handle pointing posterior | Thenar muscles | Yes | 1) The size (area of the rectified EMG signal) and latency of ‘contralateral’ and ‘ipsilateral’ MEPs elicited at the maximum stimulator output (100%). 2) The ratio between the size of ‘contralateral’ and ‘ipsilateral’ MEPs elicited in the same muscle | 10 |
| Magstim Novametrix 200 magnetic stimulator | 9 cm diameter coil, capable of generating a 2-T maximum field intensity (Novametrix Inc) | 3–7 days | 3 successive discharges with maximum output | 20% above-threshold and maximal stimulation output | Maximum stimulation band fitted tangential 3 to 4 cm lateral and posterior to the vertex to study the arm | APB | Yes | Amplitude and latency of the facilitated MEPs | 13 |
| Magstim 200 stimulator (Magstim Ltd, UK) | 12 cm diameter circular coil | Within 7 days | 3 stimulations | 100% output intensity | Above the vertex | FDI of both upper limbs | Yes | Amplitude and latency of the facilitated MEPs | 19 |
| Magstim 200 magnetic stimulator (Magstim, Whitland, South West Wales) | 9 cm mean diameter circular coil | Within 10 days and then at 40 days after stroke | At least two responses | 80%–100% (maximum output) | Placed in a tangential plane above the vertex | ADM, biceps brachii, vastus medialis, and tibialis anterior | Yes | CMCT and latencies of MEPs | 20 |
| Medicor Magstim 200 magnetic stimulator | 7 cm figure-of-eight coil for cortical stimulation | 4 days, 6 weeks, and after 3 months | At least three MEPs were recorded, and the shortest one was taken | Increasing intensity (stepwise 40–100% output) | No data available | ADM | Yes | CMCT and latencies of MEPs | 8 |
| Magstim Model 200 | 9 cm diameter coil (unclear – circular or figure-of-eight) | 1.78±0.98 (day 1) and 12.36±4.05 (day2) days after stroke onset | 2 MEP were recorded | The stimulus intensity was set at 100% power to all patients | Placed tangentially over the vertex | APB | Yes | Amplitude of MEP and CMCT | 21 |
| Magstim (Novametrix) apparatus | 1.5 Tesla circular coil (outer diameter 14 cm and inner diameter 4.5 cm) | 1, 3, 30 and 90 days after stroke | Unclear | No data available | Over the vertex | Hypothenar, biceps brachiallis, gastrocnemius and quadriceps | Yes | The shortest latency (or CMCT) and the highest amplitude of MMEPs in four responses | 22 |
| Magstim 200 stimulator | Circular coil with an outer diameter of 9 cm | Within the first week and 3 to 6 months after the event | At least 3 MEPs were recorded, and the one that had the shortest latency was taken | No data available | Over the vertex | Thenar and tibialis anterior muscles bilaterally using surface electrodes | No | Amplitude and latency of the facilitated MEPs | 14 |
| Magstim 200 stimulator | Figure-of-eight coil (no data regarding size) | Within 8 hours | 5 stimuli | Maximal magnetic stimulator outpot | Motor cortex (unclear precise location) | ADM bilaterally | Yes | Amplitude, latency and CMCT | 23 |
Abbreviations: CMCT=central motor conduction time; MEP=motor evoked potential; ADM=abductor digiti minimi; FDI=first dorsal interosseous; APB=abductor pollicis brevis, EMG=electromyography; ABP=abductor pollis brevis.