Observation Of Stereopsis In Intermittent Exotropia After Surgical Correction Background

Intermittent exotropia is the most common type of strabismus in the clinical work which accounting for 80% in exotropia. At present, the main therapy is surgical correction, evaluation of stereopsis in intermittent exotropia patients after surgery is very important. Most scholars believe that after surgical correction, the stereo visual function in patients with intermittent exotropia were improved greatly. Holmes observed the near stereoacuity in intermittent exotropia of untreated children and found that the near stereoacuity was not decreased in the initial 1-2years, so they believed that the surgical treatment can’t prevent the decrease of near stereoacuity in intermittent exotropia patients. While Yildirim found that in those who have good near steroacuity pre- and after surgical correction, surgical treatmeant can improve Distance stereoacuity after surgical treatment to orthotope.Objective:Compare the stereopsis before and after sugery in those who have intermittent exotropia and correct to orthotope. The near stereopsis and distant steropsis were observed after corrected to orthotope by operation.Methods:retrospective research. In order to investigate the changes of stereopsis before and after operation in intermittent exotropia patients, 100 cases of patients with intermittent exotropia were collected from October 2013 to January 2015 in Hebei Eye Hospital, the near stereopsis and distant stereopsis were recorded and analysed. Near stereopsis examed with Yan Shao-ming stereopsis test charts, distant stereopsis were examed with synoptophore, the near and distant stereopsis were record before surgery, and in 1 week, 1month, 3 months, 6 months after surgery. SPSS 17.0 were applied to analyse the data, and P < 0.05 was determined the difference has statistical significance.Results:Before surgery, there were 20 patients have no near steropsis, 80 patients have near steropsis, among those who have near stereopsis, 58 patients have periphery stereopsis, 19 patients has macular stereopsis, 3 patients have central stereopsis. 75 cases have no distant stereopsis, 25 cases have distant stereopsis.1 weeks after surgery,there were 16 cases have no near stereopsis, 84 cases have near stereopsis, among those who have stereopsis, 39 cases has periphery stereopsis,32 cases were macular stereopsis,13 cases have central stereopsis. 1 months after surgery, there were 10 cases have no near stereopsis, 90 cases have near stereopsis, among which 26 cases has periphery stereopsis,38 cases were macular stereopsis, 26 cases have central stereopsis. 3 months after surgery,there were 8 cases have no near stereopsis, 92 cases have near stereopsis, among which 23 cases has periphery stereopsis,39 cases were macular stereopsis,30 cases have central stereopsis. 6 months after surgery,there were 7 cases have no near stereopsis, 93 cases have near stereopsis, among which 17 cases has periphery stereopsis, 40 cases were macular stereopsis,36 cases have central stereopsis.Compared with pre-surgery, there was a significant difference(P=0.03) in 1 week after surgery, and was significant difference(P=0.00) in 1 month, 3 months and 6 months too.Compared 1 weeks with 1 months after surgery, there was a significant difference(P<0.05), while there was no significant difference between 1 months, 3 months, 6 months after surgery(P>0.005).There were 72 cases have no distant stereopsis and 28 cases have distant stereopsis 1 week after surgery. 1 months later, there were 62(62%) cases have no distant stereopsis and 38 cases have distant stereopsis. 3 months later, there were 52(62%) cases have no distant stereopsis and 48 cases have distant stereopsis. 6 months later, there were 46(62%) cases have no distant stereopsis and 54 cases have distant stereopsis.Compared with pre-surgery, there was no significant difference in 1 week after surgery, while there was significant difference in 1 month, 3 months, 6 months after surgery(P<0.05); there was no significant difference(P<0.05) between 1 months and 3 months after surgery. and there there was no significant difference(P<0.05) between 3 months and 6 months after surgery. But there was significant difference between 1 months and 6 months after surgery.Conclusions:1 In intermittent exotropia patients, the near and distant stereopsis can manifest abnormal, as to near steropsis, peripheral stereovision was most common.2 After sugery in intermittent exotropia patients, the recovery of distant stereopsis takes long time. It begin to recovery in 1 months after surgery, and even after 6 months still to progress.3 After sugery in intermittent exotropia, the near stereopsis recovery earlier, It reaches peak in l months after surgery, after that, it tends to stabilize.Successful surgical treatment of intermittent exotropia can maintain or improve the patients’ binocular function. Those who can’t obtain full recovery, Visual function training should be performed to promote visual function recovery and improved, improve the recovery of stereopsis, prevent the regression of eye position.