Table XXIIIs.

Perineal motor evoked potentials in parkinsonisms.

Reference	Objective	No. of patients	Stimulation site	Recording site	Electrode type	Results	Evidence
Pellegrinetti et al., 2003	To determine the diagnostic value of pMEPs in MSA	13	Motor cortex; LS roots	BC	Needle	↑ CCT: 15%; ↑ Lat of cortical and peripheral responses: 8%	Class 2
Winge et al., 2010	To determine the diagnostic value of pMEPs in the differential diagnosis of parkinsonisms	14 MSA; 8 PSP; 6 IPD	Motor cortex; LS roots	EAS		N.D. between groups	Class 2

Abbreviations: pMEPs=perineal motor evoked potentials; MSA=multiple system atrophy; PSP=progressive supranuclear palsy; IPD=idiopathic Parkinson’s disease; LS=lumbosacral; BC=bulbocavernosus muscle; EAS=external anal sphincter muscle; CCT=central conduction time; Lat=latency; N.D.=not significantly different.