Multiple System Atrophy And The Characteristics Of External Anal Sphinter Electromyography

【background】:Multiple system atrophy(MSA),a progressive neurodegenrative disease of undetermined etiology,occurs sporadically and causes parkinsonism and cerebellar,autonomic,urinary,and pyramidal dysfunction in many combinations.It has been described in three different ways:olivoponto-cerebellar atrophy(OPCA), striatonigral degeneration(SND,and the Shy-Drager syndrome.(SDS).In recent years glialcytoplasmic inclusions have been described in oligodendrocytes that are present in the brains of all patients with MSA of what ever domination.The parkinsonian features include bradykinesia with rigidity,postural instability, hypokinetic speech,and often tremor,usually with a poor or unsustained response to chronic levodopa therapy.The cerebellar dysfunction consists of ataxia of gait,limb movements and speech,and disorders of extra-ocular movements Autonomic insufficiency results in orthostatic hypotension,often with an inadequate heart rate response to standing,male erectile dysfunction(MED),constipation,and decreased sweating Urinary symptoms include urgency,frequency,nocturia,incomplete bladder emptying,and incontinence.MSA is short of typical characteristics in the beginning of the disease,correlated symptoms appear slowly.And we know this syndrome not enough,it is easily to confuse it with orthostatic hypotension,syncope,Parkinson disease and progressive supranuclear palsy.So it is difficult to diagnose MSA especially early diagnosis.Since 1978.It is reported that more than 500(External anal sphinter electromyography,EAS-EMG) consequences of cases.there is a abnormality exceeded 70%.Those results may reflect a trend for increased motor unit potential(MUP) amplitude duration,number of active MUPs,and the presence of spontaneous potential.【objective】:To evaluate data of anal sphincter EMG in multiple system atrophy(MSA),to analy the characteristics of EAS-EMG,to investigate the value of EAS-EMG in the diagnosis of MSA.【Method】:we collect clinical features,physical examination and EAS-EMG values of all MSA and PD patients in SIR RUN RUN SHAW HOSPITAL from February 2007 to February 2008.【Result】:We collected 20 MSA patients.18(90%) has positive result(neurogenic change).【Conclusion】:EAS-EMG should be abnormal in some exent in 90%of all MSA patients,Electroneurophysiology examination is helpful to diagnosis for MSA and eapically improve the accarucy of diagnosis for this disease.