ABSTRACT
AIM: To discuss and evaluate how different types of strabismus impact on the recovery of distance and near stereoacuity after strabismus surgery. METHODS:We selected 72 cases of strabismus who were treated in our hospital. They were divided into four groups: Group 1 as constant non - accommodative esotropia;Group 2 as intermittent exotropia; Group 3 as constant exotropia; Group 4 as exotropia V sign with inferior oblique hyperfunction. The distance stereoacuity were examined by synoptophore and the near stereoacuity was examined by Shaoming Yan's stereogram. Above examination data was collected and recorded before surgery,7d,1,3,and 6mo after surgery. RESULTS: The 72 patients' distance and near stereoacuity were significantly improved after their surgery, compared with their previous binocular vision. The improvement showed statistical significant(P<0.05). The recovery of Group 2's distance and near stereoacuity had been proved superior to that of Group 1, Group 3, and Group 4. The changes in the distance and near stereoacuity of Group 2 were statistically significant (P<0 05). There were no statistically significant changes in the distance and near stereoacuity of Group 1, Group 3, and Group 4 after the surgeries(P>0.05). The damage of distance stereoacuity (0 cases) was more severe than the damage of near stereoacuity (19 cases, 26%). After the surgeries, near stereoacuity's (51 cases, 71%) recovery was significantly superior to the distance stereoacuity's recovery(17 cases,24%). At 1mo after the surgeries,the improvement of distance and near stereoacuity was most obvious. CONCLUSION:Postoperative recovery of distance and near stereoacuity varies as per strabismus type. Intermittent exotropia's patients show the best recovery of distance and near stereoacuity after the surgeries. The clinical results on the recovery of distance and near stereoacuity after surgery for constant non -accommodative esotropia, constant exotropia and exotropia V sign with inferior oblique hyperfunction are consistent. As the distance stereoacuity of the patients with strabismus has more severe damage,the recovery of near stereoacuity is superior to that of distance stereoacuity.
ABSTRACT
AIM: To explore the long-term efficacy of Q-factor guided laser epithelial keratomleusis ( LASEK ) for myopia and astigmatism with positive Q-factor. METHODS: There were 158 eyes which were myopia and astigmatism with positive Q- factor taken in two groups randomly: 86 eyes accepted Q - factor guided LASEK as observation group and 72 eyes accepted routine LASEK as control group. The difference between the two groups about all data was similar. The uncorrected visual acuity ( UCVA ) and the best corrected visual acuity ( BCVA ) as well as diopter, ocular tension, corneal topography, Keratometry value K, aspherical factor Q, Higher-order aberrations ( HOA ) , corneal thickness by ultrasound and, contrast sensitivity ( CS ) , Haze were examined and compared before and after surgery. All the cased were followed up for 14d, 1, 3, 6, 12mo. And there were no statistical difference among the data before surgery. RESULTS: After 12mo there were no statistical difference between the two groups about UCVA and BCVA. But the safety index of observation group was 1.10, that of control group was 1. 07. The validity index of observation group was 1. 06, that of control group was 0.99. The HOA of observation group was 0. 45±0. 17μm, and that of control group was 0. 72±0.25μm, there was statistically significant difference (t=-8. 193,P=0. 000). Q factor of observation group was 0. 41±0. 17, that of control group was 0. 77±0. 22, there was significant difference (t=11. 377,P = 0. 028). The contrast sensitivity of 3mo post surgery of patients in the observation group returned to the level of before surgery. But in the control group the contrast sensitivity of the patients did not returned until 6mo. CONCLUSION:Q-factor guided LASEK for myopia and astigmatism with positive Q-factor is stable, safe and effective. The operation allow for reducing the high order aberrations, maintaining the most asphericity of cornea, saving more in corneal tissue, which cause faster recovery of contrast sensitivity, less haze and better visual quality.