Investigation Of Multiofcal Visual Evoked Potential In Preoperative And Postoperative Exotropia

Objective:To study the characteristic change of multifocal VEP in Postoperative children with shuq and the relationship between the characteristic change of multifocal VEP and the change of stereoscopic vision to provide the theory of the exotropic operation opportunity and the new therapeutic evaluation.Methods:The multifocal pattern VEP of both eyes of 80 exotropias,including20 normal visual exotropias、60 exotropic amblyopes(20 lingter-amblyopes 、20mid-amblyopes、20 weight-amblyopes) and alll subjects were recorded by Roland Retiscan Multiofcal Visual Evoked response imaging system made by Germany Roland company. The latencies and amplitudes of P waves were analysed.Changes in different retinal area between pre-operation and 1 month 、3months and 6 months.Result:1 、 The amplitudes denstiy and the lantencies of P waves at six eccentricities.In the normal visual exotropias group,there were no significant differences after surgery.The amplitudes denstiy in the exotropic lingt-amblyopes group and exotropic mid-amblyopes group were improved at the first 、second、third eccentricity,while in the exotropic weight-amblyopes group there were different at six eccentricities after surgery.2、The latencies and amplitudes denstiy of P waves in upper and lower retinal hemifields.In the normal visual exotropias group, the latencies and amplitudes denstiy of P waves in upper and lower hemifields were no differences after surgery. while The amplitudes denstiy of the exotropic lingt-amblyopes group and exotropic mid-amblyopes group were markedly improved and the latencies were shorted compared with the group which had a surgery.3、The latencies and amplitudes denstiy of P waves in nasal and temporal retinal hemifieldsCompared with the pre-operational group, the normal visual external obliquepostoperative group’s latencies and amplitudes denstiy of P waves in nasal and temporal retinal hemifields were no differences, while in the exotropic amblyopes external oblique postoperative groups,the amplitudes denstiy were improved and the latencies were cut down.The nasal retinal hemifields,latencies are improved more than temporal retinal hemifields in exotropic lingter-amblyopes,while the increase of latencies between the nasal side and the temporal retinal hemifields is no difference in mid-amblyopes and weight-amblyopes.4、The comparisonon binocularvision after surgeryand before surgery:Three-degree visual function and nearstereoacuity of patients improved differently after surgery(P<0.05).There was no significant difference between 1month 、3months and 6 months in the group of the weight-amblyopes(P>0.05).the relationship between the characteristic change of multifocal VEP has significant relationship with the change of stereoscopic vision.Conclusion:1、In the exotropic amblyopes,compared with the temporal retinal hemifieldsthe contaminate in the nasal retinal hemifields were more serious at the visual transmission iter.2、The nasal retinal hemifields,latencies are improved more than temporal retinal hemifields in exotropic lingter-amblyopes,while the increase of latencies between the nasal side and the temporal retinal hemifields is no difference in mid-amblyopes and weight-amblyopes.The nasal retinal hemifields,latencies are improved more than temporal retinal hemifields in exotropic lingter-amblyopes,while the increase of latencies between the nasal side and the temporal retinal hemifields is no difference in mid-amblyopes and weight-amblyopes.3、To provide the new clincal theory ofthe therapeutic evaluation.