Analysis Of ENG In Multiple System Atrophy

Background Multiple system atrophy (MSA) is an neurodegenerative disease of unknown aetiology, which affects extrapyramidal system, pyramidal system, cerebellum and autonomic nervous system. Based on its main clinical symptoms, MSA is divided into three subtypes:predominant parkinsonism(MSA-P), cerebellar ataxia(MSA-C) and autonomic dysfunction(MSA-A). The diversity of clinical manifestations of MSA brings great difficulty in making diagnosis. MSA may cause the change of eye movement function, such as scanning dysfunction, nystagmus, etc. Electronystagmography is a method to check the eye movement through the machine, then we can have a quantitative analysis on it. The change of eye movement caused by MSA can be recorded and analyzed to help in the diagnosis and assessment of MSA.Objective To record and analyze the eye movement function of the MSA patients though ENG and help in the diagnosis and assessment of MSA.Methods Select the MSA patients from Qilu hospital since June 2014 to April 2015. We have 15 cases(MSA-P 6 cases,MSA-C 8 cases). Choose 10 normal persons as control group.Then we give both two group the ENG test,which including spontaneous nystagmus,gaze,saccades,smooth pursuit and positioning downbeat nystagmus.Do statistics of the result and compare the two groups.Results 1.Spontaneous nystagmus:None of the patients was recorded with a spontaneous nystagmus in bright chamber.6/15 were recorded with consecutive square wave and 3/15 were recorded with several times of nystagmus.2.Gaze test:Only 1 patient was recorded with several times of nystagmus when gazing to the left(15d).3.Saccades test:The control group got smooth curve,without obvious overshoot or inadequate. Both MSA-P and MSA-C was recorded with consecutive overshoot or inadequate.The delayed time of MSA group was extended(P<0.05).4.Smooth pursuit:The control group got smooth curve(Ⅰ and Ⅱ type).MSA group was recorded with Ⅲ and Ⅳ type curve.Comparing with the control group, the gain value were reduced in MSA-P and MSA-C(P<0.05),while the difference of CP% had no statistical significance(P>0.05).5.Optokinetic nystagmus test:Comparing with control group,the gain value were reduced in both MSA-P and MSA-C(P<0.05).The differences of CP% had no statistical significance(P>0.05).Conclusions patients of multiple system atrophy can appear with different degree of abnormal oculomotor movements. Saccades function is weakened, appear with different degree of overshoot, inadequate and extended delayed time. Smooth pursuit function is decreased, shown as unsmooth curve and significantly reduced gain value. Optokinetic nystagmus is impaired, with significantly reduced gain value.Those abnormal oculomotor movements in MSA patients indicate that there are different degrees of damage in regions such as brainstem reticular formation, raphe nuclei, etc.