Research Of The Cortical Multi-point Recorded Somatosensory Evoked Potentials In The Patients With Focal Dystonia

Objective:Research the cortical multi-point recorded somatosensory evoked potentials in thetype of focal dystonia by analyzing the central component values to suggest the possiblepathogenesis of focal dystonia and provide the objective indicators for early diagnosisand screening.Methods:1.Spasmodic torticollis: Cortical multi-point recorded median somatosensoryevoked potentials were investigated in30patients affected by spasmodic torticollis and30controls.30controls were researched in two paradigms, respectively, for group I(17healthy volunteers were recorded in the head to the left deviation on state of30degrees and13healthy volunteers were recorded in the head to the right deviationonstate of30degree, matching with the patients) and group Ⅱ (30healthy volunteers withthe head in the normal position).The interpeakampitude of N20/P25, P22/N30werecompared between both sides.2. Blepharospasm: Cortical multi-point recorded trigeminal nerve somatosensoryevoked potentials were investigated in24patients with blepharospasm and19controls.The interpeak lantency of N13-P19, P19-N30, N13’-P19’, P19’-N30’ andinterpeak amplitude of N13/P19, P19/N30, N13’/P19’, P19’/N30’were compared withthe controls.Results:1.Spasmodic torticollis:(1)Routine median somatosensory evoked potentials: The interpeak amplitude ofcortical componet N20/P25of the control Ⅰand controlⅡin bilateral side had nosignificant differences (P>0.05). The interpeak amplitude of cortical componet N20/P25 in bilateral side of patients had no significant differences (P>0.05). The interpeakamplitude of cortical componet N20/P25in bilateral side of patients and control I hadno significant differences (P>0.05).(2)Cortical multi-point recorded median somatosensory evoked potentials: Theinterpeak amplitude of cortical componet P22/N30of thecontrolⅠand controlⅡinbilateral side had no significant differences (P>0.05).The interpeak amplitude of corticalcomponet P22/N30in contralateral side of patients was significantly higher than inipsilareral side(P<0.05).The interpeak amplitude of cortical componet P22/N30incontralateral side of patients was higher than in contralateral side of control I(P<0.05).The interpeak amplitude of cortical componet P22/N30in ipsilateral side of patients andcontrol I had no differences(P>0.05).2. Blepharospasm:(1)Routine trigeminal nerve somatosensory evoked potentials: The interpeaklatency of cortical componet N13-P19, P19-N30in the controls and patients had nosignificant differences(P>0.05).The interpeak ampitude of cortical componet N13/P19and P19/N30in the patients were significantly higher than in controls (P<0.05).(2)Cortical multi-point recorded trigeminal nerve somatosensory evokedpotentials: The interpeak latency of cortical componet N13’-P19’, P19’-N30’ in thecontrols and patients had no significant differences (P>0.05).The interpeak ampitude ofcortical componet N13’-P19’and N19’/N30’ in the patients were significantly higherthan in controls (P<0.05).Conclusions:1.There is increasing excitement in supplementary motor cortex of thecontralateral to head deviation in the patients with spasmodic torticollis.2.There are increasing excitement in pons, thalamus-basal gangalia,bilateralprimary sensory cortex and supplementary motor cortex of the patients withblepharospasm.3.Cortical multi-point recorded somatosensory evoked potentials contribute to thestudy of diagnosis and pathogenesis in patients with focal dystonia.