Study On Binocular Visual Function In Intermittent Exotropia Patients

Intermittent exotropia is the most common type of exotropia.The ability to control the binocular normotopia was gradually weakened in the vast majority of intermittent exotropia patients,and exotropia showed a continuous deteriorating trend.Its mechanism is not clear at present.In this study,the possible mechanism of intermittent exotropia was investigated by measuring the fusion range of the study object,converged fusion and diverged fusion,as well as near and distant stereoscopic vision.And the effects of intermittent exotropia on near and distant stereoscopic vision were investigated.Method:The pure intermittent exotropia patients were selected as intermittent exotropia group,who were not treated with any treatment,were able to cooperate well with the examination and the exclusion of other diseases in the Department of Ophthalmology.The normal children in the same period were selected as normal control group.The binocular fusion function and far and near stereo vision of the two groups were measured by using the synoptophore and phoropter.Result:1 The measurement results of synoptophore showed: The coincident point of intermittent exotropia group was significantly externally deviated compared with the normal control group.The difference was statistically significant(P<0.01).There was no statistical significance in diverged fusion between the intermittent exotropia group and the normal control group(P>0.05).The converged fusion in the intermittent exotropia group was significantly smaller than that of the normal control group.(P<0.01).2 The distant horizontal measurement results of axicon showed:1.There was no statistically significant in the distant horizontal discrete fusion between the intermittent exotropia groups and the normal control group.(P>0.05).(2)The distant horizontal diverged fusion in the intermittent exotropia group was significantly larger than that of the normal control group.The difference showed statistical significance between the two groups(P<0.01).(3)The distant horizontal converged fusion in the intermittent exotropia group was significantly lower than that of the normal control group.The difference showed statistical significance between the two groups(P<0.01).The near horizontal measurement results of axicon showed:(1)The fusion range of the intermittent exotropia group was less than that of the normal control group.The difference showed statistical significance between the two groups(P<0.05).(2)The near distance horizontal diverged fusion showed no significant difference between the intermittent exotropia group and the normal control group.The difference showed no statistical significance between the two groups(P>0.05).(3)The near distance horizontal converged fusion in the intermittent exotropia group was significantly smaller than that of the normal control group.The difference showed statistical significance between the two groups(P<0.01).3 Stereoscopic visual examination results: Random point diagram examination by synoptophore: The distant stereopsis in the intermittent exotropia group was significantly lower than that of the control group.The difference showed statistical significance between the two groups(P<0.01).Frisby stereoscopic vision examination card: The near stereoscopic vision in the intermittent exotropia group was significantly lower than that of the control group.The difference showed statistical significance between the two groups(P<0.01).Conclusion:1 Discrete fusion of hyperfunction may be one of the mechanisms of intermittent exotropia.2 Coincident point examination by synoptophore showed that the coincident point of intermittent exotropia patients was significantly externally deviated.3 The distant and near stereoscopic visions in the intermittent exotropia group were lower than those of normal control group,particularly evident in the distant stereoscopic vision.It was speculated that the stereoscopic visual impairment of intermittent exotropia might firstly occur in the distant stereoscopic vision.