P202: Comparing objective measures of neurodegeneration in multiple sclerosis (MS)

The Use of Motor-Evoked Potentials in Clinical Trials in Multiple Sclerosis

“…Reduced MEP amplitude is correlated with EDSS and, independently of its pathogenesis (conduction block or axonal loss), should be considered an early marker of the dysfunction of the motor pathways in patients with MS. 22 In a prospective study including 89 patients with MS, a multivariate analysis including multimodal EPs and OCT measurements (retinal nerve fiber layer and ganglion cell layer) found the MEP amplitude of the upper limbs to be the strongest measure correlating with EDSS, and the receiver operating characteristics curve analysis showed an accuracy and discriminating power of 0.8 for detecting progression, as measured by the EDSS .4. 23 There also exists a correlation between MEPs, brain, and spinal MRI and EDSS, and a model for explaining disability in MS revealed that MEPs provide additional information to MRI. 24 In a prospective study of 60 patients with MS, the best correlations among all atrophy measurements by MRI and EP variables were for the MEP amplitude of the lower limbs with the volume of T1 lesions and the following MRI measurements of atrophy: white matter volume and gray matter volume.…”

“…43 Motor-evoked potentials, particularly the MEP amplitude ratio, have never been used as a measure in clinical trials for neuroprotective agents, although they seem to be a very promising tool to measure the neuroprotective and remyelinating effect of drugs because of their highest correlation to EDSS among EP measurements and other measurements of neurodegeneration in MS (OCT and atrophy in MRI). 23,25 Ceiling effects in patients with progressive MS may prevent the use of EPs, especially SEPs from and MEPs to the lower limbs. For this reason, MEPs to the upper extremities are recommended to monitor progressive disease.…”

“…In a prospective study including 89 patients with MS, a multivariate analysis including multimodal EPs and OCT measurements (retinal nerve fiber layer and ganglion cell layer) found the MEP amplitude of the upper limbs to be the strongest measure correlating with EDSS, and the receiver operating characteristics curve analysis showed an accuracy and discriminating power of 0.8 for detecting progression, as measured by the EDSS >4. 23…”

“…Motor-evoked potentials, particularly the MEP amplitude ratio, have never been used as a measure in clinical trials for neuroprotective agents, although they seem to be a very promising tool to measure the neuroprotective and remyelinating effect of drugs because of their highest correlation to EDSS among EP measurements and other measurements of neurodegeneration in MS (OCT and atrophy in MRI). 23,25…”

Evoked potentials are of little use in the diagnosis or monitoring of MS: No

“…In a prospective study including 89 MS patients, a multivariate analysis including multimodal EP and OCT measures (RNFL and GCL), the MEP amplitude of the upper limbs was the strongest measure correlating with EDSS in the multivariate analysis, and receiver operating characteristics (ROC) curve analysis showed an accuracy and discriminating power of 0.8 for detecting progression to EDSS >4. 7 Given the good correlations of EPs in detecting disease progression, EPs may be used to monitor the effects of drugs acting on nerve conduction and on neural protection and regeneration. In fact, several recent clinical trials designed to find neuroprotective effects in MS used EPs as objective tools to measure the therapeutic effects.…”