|
| No. | Reference | No. of samples | IONM modalities used | Stimulation parameters | Muscles used to monitor MEP | Improvement criteria | Results |
|
| 1 | Barley et al. (2010) | One (15 months old boy) | TcMEP and SSEP | C1.-C2 scalp electrode positioning, current stimulation (145 mA to 187 mA for the left extremities and 175 mA to 200 mA for the right extremities) | Bilateral quadriceps femoris, tibialis anterior, gastrocnemius, sphincter, abductor pollicis brevis, abductor hallucis | Not mentioned | TcMEP response of the left APB had increment in amplitude. The patient had observable left upper extremity improvement |
|
| 2 | Voulgaris et al. (2010) | 25 (2 had no IONM results) | TcMEP, EMG | C1–C2 with multipulse current stimulation, 0 mA to 200 mA, stimulus duration 0.2 ms to 0.5 ms | Not mentioned | >50% MEP amplitude improvement | 17 patients with >50% improvement had better VAS score improvement |
|
| 3 | Rodrigues et al. (2011) | One (case report) | SSEP, MEP, and free-running EMG | C3-C4 stimulation | Not mentioned muscles’ names specifically but monitoring covered L3-S2 myotomes | Not mentioned | MEP improved as much as 30%, and patient had returned to sports |
|
| 4 | Raynor et al. (2013) | 386 patients had IOM signal improvement out of 12375 patients that had spinal surgeries over 25 years | DNEP, TcMEP, spontaneous EMG, triggered EMG, dermatomal SSEP | C3-C4 TcMEP scalp electrode stimulation montage | Upper extremity TcMEP was recorded from the deltoid, flexor/extensor carpi radialis, and/or abductor digiti minimi/abductor pollicis brevis. Lower extremity TcMEP was recorded from the anterior tibialis, medial gastrocnemius, and/or extensor hallucis longus | Not mentioned | The results did not mention specifically TcMEP improvement, but out of the modalities used, 88.7% patients had IOM signal improvement but one patient out of this percentage had permanent neurological deficit |
|
| 5 | Visser et al. (2014) | 74 patients | TcMEP | Cz–Fz with monophasic stimulation and C3–C4 with biphasic stimulation | For the lower limbs: the quadriceps muscle (L2-L4), the tibialis anterior muscle (L4-L5), the hamstrings (L5-S1), or the gastrocnemius muscle (S1-S2). For cervical: the bilateral trapezoid muscle (C2-C4), the biceps (C5-C6), and the triceps muscle (C7-C8) of the arm; the extensor muscles of the forearm (C6-C7); or the abductor digitus V muscle (C6-C8) | >200% of amplitude increment | There is a correlation between the duration of symptom onset and the MEP improvement. MEP improvement can be accurate if the symptom onset duration is less than half a year |
|
| 6 | Wang et al. (2016) | 59 patients that had cervical myelopathy underwent laminoplasty or laminectomy | MEP and SSEP | Not mentioned | Not mentioned | Not mentioned | Patients that had MEP signal improvement had a significant mJOA improvement rate. MEP amplitude was found to be a more accurate parameter compared to MEP latency in predicting surgery outcome |
|
| 7 | Dhall et al. (2017) | 32 | EMG, MEP, SSEP (not used for the study) | 100 V–1000 V constant voltage stimulation, C1–C2 anodal stimulation, double train with a total of 9 pulses, 50 ms pulse width, 1.7 ms interstimulus, 13.1 ms ISI | Not mentioned | Comparison with the AIS grade and BASIC score of MRI images | MEP outcome (present) highly correlated with the better AIS grade and BASIC grade |
|
| 8 | Piasecki et al. (2018) | 18 | MEP, SSEP (not used for the study) | 50 V–150 V C1–C2 biphasic stimulation, 5 to 7 train pulses, 500 Hz, 1 ms interstimulus pulse | 1 upper limb muscle (control), bilateral tibialis anterior/bilateral abductor hallucis | >20% of AUC MEP, >50% of ZCQ score | The MEP improvement was related to the early follow-up functional outcome |
|
| 9 | Wi et al. (2019) | 29 patients had improvement of IONM signals out of 317 cases | MEP and SSEP | Not mentioned | Upper extremity TcMEP was recorded from the deltoid, triceps, and thenar muscles. Lower extremity TcMEP was recorded from the anterior tibialis and abductor halluces | Comparison with MISS, SF-36, JOA, NDI, and Oswestry Disability Index | The patients with MEP improvement had a better MISS improvement rate while the patients with SSEP improvement only had a better SF-36 improvement rate |
|
| 10 | He et al. (2020) | One (case report) | MEP and free-running EMG | Not mentioned | Bilateral iliopsoas, rectus femoris, tibialis anterior, and medial gastrocnemius | Not mentioned | MEP improvement aligned with the patient’s relieved symptoms |
|
