Objective To analyze the changes in the amplitude of accommodation and the accommodative convergence (AC) /accommodation(A) ratio in the early stages after laser in situ keratomileusis (LASIK) in the patients with high myopia.
Methods Fifty one high myopic patients, dividing into 2 groups according to their habitual correction (Group-G wearing glasses in 52 eyes and Group-C wearing contact lenses in 50 eyes), were treated by LASIK. Refraction measured with MPMVA, amplitude of accommodation measured with push-up test , their phoria on near (40cm) and distance (6m) with Von Graefe were measured three times (before surgery，1 month and 6 months after surgery)and accommodation stimulus ratio(AC/A) was determined through phoria values’ calculation. The soft ware SPSS 13.0 was used in statistic analysis.
Results The amplitude of accommodation of postoperative 1 month were significantly smaller than that of preoperative in glasses groups and in contact lens groups（P<0.05）. There was no significant difference of accommodative amplitude postoperative 6 months , comparing preoperative values in two groups (P>0.05). We found no significant difference of the accommodative amplitude before surgery and, postoperative 1 and 6 months between two groups (P>0.05). At 1 month postoperatively, amplitude of accommodation was significant smaller than preoperative values in wearing glasses Group-G（P＜0.05）. However, there was no significant difference at 6 months after surgery (P> 0. 05). In Group-C: there was no significant difference of the calculative AC/A ratio before surgery and, postoperative 1 and 6 months (P> 0. 05).
Conclusion The changing trends of postoperativeaccommodativeamplitude are quite same in these two groups and regain their preoperative level of wearing glasses at 6 months after surgery.For the patients who weared glasses or contact lens for a long time, amplitude of accommodation and the calculative AC/A ratio before surgery and postoperative are not affected by myopic refractive surgery. |
