摘要
目的 :评价激光性角膜原位板层磨镶术 (laserinsitukeratomileusis,LASIK)对视盘及视神经的早期影响。方法 :对拟行LASIK手术的 32只近视散光眼于术前进行视网膜断层扫描仪 (HRT)检查 ,并分别于术后第 10天、第 2个月进行随访。对所测数据进行统计学处理和相关性分析。结果 :手术前视网膜神经纤维层厚度 (RNFL)和视网膜神经纤维层截断面积分别为 (0 .2 8± 0 .11)mm2 和 (1.41± 0 .39)mm2 ,术后第 10天时为 (0 .2 4± 0 .10 )mm2 和 (1.2 1± 0 .49)mm2 ,手术前后比较 ,数值减少 ,差异有显著性 (P <0 .0 5 )。术后第 2个月时分别为 (0 .2 6± 0 .12 )mm2 和 (1.2 8± 0 .49)mm2 ,与手术前比较 ,两者无明显差异 (P >0 .0 5 )。视乳头杯 /盘比显示 ,第 10天及第 2个月与术前的数值比较 ,虽有差异但不具有统计学意义 (P >0 .0 5 )。同时显示视网膜神经纤维变薄与年龄和屈光度成正相关。结论 :LASIK手术早期可能会对视盘和视神经层有影响 ,但存在恢复趋势 。
Objective:Laser-assisted in situ keratomileusis(LASIK) has become widely used to correct myopia. One of the safety concerns about LASIK is its effect on the posterior segment of the eye. This study evaluates the effects of LASIK on retinal nerve fiber layer thickness and the optic disc.Methods:Thirty-two consecutive eyes,which met the inclusion criteria for undergoing LASIK,were enrolled in this prospective study. Patients were eligible for inclusion if they had a best corrected visual acuity of 20/20,normal intraocular pressure(IOP)(<21 mmHg),and a healthy looking optic disc. All LASIK surgery was performed by the same surgeon using NIDEK EC-5000 excimer laser(NIDEK,Gamagori,Japan). Keratectomies were performed using the chiron automated corneal shaper microkeratome. Confocal scanning laser ophthalmoscopy(heidelberg retina tomograph,HRT) examination was performed pre-operatively and at 10 days and 2 months postoperatively. Three images were obtained and the mean tomographic HRT parameters(Mean retinal nerve fiber layer thickness,cross-sectional area and cup-disc ratio,etc.) values were compared by paired t test.Results:The mean age of the patients was (27.29±8.95)years. The mean attempted correction was (9.39±3.24)D and the mean astigmatic error was (1.25±0.85)D. The average retinal fiber layer(RNFL) thickness and cross-sectional area were (0.28±0.11)mm 2 and (1.41±0.39)mm 2 before surgery,respectively,and (0.24±0.10)mm 2 and (1.21±0.49)mm 2 at 10 days after surgery,with a decrease of 13% in RNFL(P<0.001) and 14% in the cross-sectional area(P<0.05). This was significantly less(P<0.05) at 10 days postoperatively compared to the pre-operative measurement. However,the decrease was not statistically significant between pre-operative examination and postoperative examination at 2 months. RNFL thickness and cross-sectional area were (0.26±0.12)mm 2 and (1.28±0.49)mm 2 at 2 months(P>0.05). There is no marked change in the cup-disc ratio,which was 0.15±0.13 pre-operatively and 0.16±0.16 at 10 days(P>0.05) and 0.14±0.12 at 2 months(P>0.05). A statistically significant passive association was found between retinal nerve fiber layer thickness and pre-operative refraction(r=-0.59,P<0.05). There was also a significant correlation between retinal nerve fiber layer thickness and age(r=-0.37,P<0.05),but no significant correlation between retinal nerve fiber layer thickness and the duration of surgery.Conclusion:The study supported the hypothesis that there is thinning in the nerve fiber layerdue to increased pressure during LASIK but the changes appear to be temporary. The possible causes for those changes are direct irradiation,acoustic shock waves and increased IOP,etc. Further investigation is needed.
出处
《眼视光学杂志》
2002年第3期145-147,共3页
Chinese Journal of Optometry & Ophthalmology
