Application Of Vestibular Evoked Myogenic Potentials In The Diagnosis And Treatment Of Unilateral Meniere’s Disease

Objectives To explore the clinical characteristics of vestibular evoked myogenic potential in unilateral Meniere’s patients.To explore the changes of myogenic potential induced by intratympanic injection(dexamethasone or gentamicin)in patients with Meniere’s disease.Methods 30 cases of unilateral Meniere’s disease and 16 healthy adults were underwent by cervical vestibular evoked myogenic potentials(cVEMP)and ocular vestibular evoked myogenic potentials(oVEMP).We analyzed and compared the parameters between the two groups.20 cases of accepted intratympanic injection dexamethasone.10 cases of accepted intratympanic injection gentamicin.We analyzed the changes of vestibular evoked myogenic potentials before and after injection.ResultsUnilateral Meniere’s disease affected ear compared with normal control group: The incidence of cVEMP was decreased(p=0.000),the threshold value was increased(p=0.000),the amplitude was decreased(p=0.000),the amplitude ratio was increased(p=0.000),and the asymmetry ratio was increased(p=0.000).The incidence of oVEMP was decreased(p=0.001),the threshold was increased(p=0.000),the latency of N1 was prolonged(p=0.000),the interval became short(p=0.001),and the amplitude wasdecreased(p=0.000).Unilateral Meniere’s disease affected ear compared with control ear:The incidence of cVEMP was decreased(p=0.000),The latency of P1 was prolonged(p=0.012),and the latency of N1 was prolonged(p=0.033).The incidence of oVEMP was decreased(p=0.032).Unilateral Meniere’s disease contorl ear compared with normal control group:The threshold value of c VEMP was increased(p=0.000),the amplitude was decreased(p=0.000),the amplitude ratio was increased(p=0.000),and the asymmetry ratio was increased(p=0.000).The threshold value of oVEMP was increased(p=0.000),the latency of N1 was prolonged(p=0.000),the interval became short(p=0.001),and the amplitude was decreased(p=0.000).After treatment compared with before treatment:The dexamethasone group: The threshold value of cVEMP was decreased(p=0.007),the amplitude was increased(p=0.012),the amplitude ratio was decreased(p=0.041),and the asymmetry ratio was decreased(p=0.032).The threshold value of oVEMP was decreased(p=0.002),the amplitude was increased(p=0.003),the latency of N1 became short(p=0.004).The gentamicin group: The incidence of cVEMP and o VEMP were decreased,the threshold values were increased,but there were no significant differences compared with those before treatment.ConclusionCompared with healthy adults,the incidence and amplitude of VEMPs(cVEMP and oVEMP)in unilateral Meniere’s disease affected earwere decreased,and thethreshold value of VEMPs were increased.It is interesting that unilateral Meniere’s disease control ear compared with healthy adult group,the incidence,amplitude also decreased to a certain extent,and the threshold also increased.Those show that the control ear of unilateral Meniere’s disease also appeared decline in the function of saccule and utricle.The incidence and amplitude of cVEMP and oVEMP were increased and the thresholds were decreased after the intratympanic injection of dexamethasone.The results show that the intratympanic injection of dexamethasone can effectively relieve the hydrops of saccule and utricle and improve the symptoms of patients.The incidence of cVEMP and oVEMP were decreased and the threshold values were increased after the intratympanic injection of gentamicin.Those show that gentamicin treatment can effectively destroy the function of the saccule and utricle,so as to achieve the purpose of vertigo control.But because the number of cases is too small,we failed to find statistically significant results.