先天性白内障形觉剥夺时间对眼主要屈光参数的影响

目的评价先天性白内障形觉剥夺时间对眼屈光系统主要参数的影响。方法选取单眼先天性白内障患者48例,年龄(6个月～35岁);术前综合验光仪进行主觉验光,对不能配合主觉验光者进行检影验光,按形觉剥夺时间分为0-4a组(13眼)、4-8a组(18眼)、>8a组(17眼),测量双眼眼轴长度、角膜曲率。最佳矫正视力低于正常视力,或者两眼最佳矫正视力相差两行及其以上者为弱视。结果先天性白内障患者形觉剥夺时间在0-4a组、4-8a组,眼轴长度在双眼之间差异均无统计学意义(P=0.563、0.547);剥夺时间与双眼眼轴长度差值(0.92±0.41)mm、(1.64±1.49)mm并无明显相关性(P=0.703、0.890);各形觉剥夺时间段,双眼角膜曲率差异均无统计学意义(均为P>0.05)。在形觉剥夺时间大于8a组:双眼眼轴长度之间差异有统计学意义(P<0.01);且眼轴长度差值(3.05±1.88)mm与形觉剥夺时间正相关(r=0.816,P<0.01);但是角膜曲率在两眼之间差异均无统计学意义(均为P>0.05)。42例患者双眼等效球镜屈光度绝对值差值(3.66±3.00)D与眼轴长度绝对值差值(2.23±1.46)mm呈正相关(r=0.782,P<0.01)。结论先天性白内障在形觉剥夺初期,并不对眼轴长度产生明显影响,早期的形觉剥夺主要是形成形觉剥夺性弱视;单眼先天性白内障引起的屈光参差,主要由眼轴延长引起。

Effect of form deprivation time on main refractive parameter in congenital cataract

Objective To evaluate the effect of form deprivation time on the main refractive parameter in congenital cataract.Methods Forty-eight congenital cataract patients(48 eyes) aged from 6 months to thirty-five years were chosen,the subjective refraction was determined,and the retinoscopy was performed in patients,who unable to receive the subjective refraction examination.Based on form deprivation time,the patients were divided into from 0 year to 4 years group(13 eyes),from 4 years to 8 years group(18 eyes) and more than 8 years group(17 eyes),the binocular axis length and corneal curvature were measured.The amblyopia was defined as the best corrected visual acuity below normal vision,or the difference of binocular best corrected visual acuity equal to or more than two lines.Results In from 0 year to 4 years group and from 4 years to 8 years group,the difference between binocular axial length was not significant(P= 0.547,0.563),and the deprivation time was not related with the difference in binocular axial length,which were(0.92±0.41)mm and(1.64±1.49)mm(P=0.890,0.703);The difference of binocular corneal curvature had also no significant difference in all deprivation time points(all P>0.05).In more than 8 years group,there was significant difference in difference of binocular axis length(P<0.01),and the deprivation time was related with the difference in binocular axial length,which was(3.05±1.88)mm(r=0.816,P<0.01),but there was no statistical difference in difference of binocular corneal curvature(all P>0.05).The absolute value of binocular spherical equivalence difference(3.66±3.00)D was positive related with the absolute value of axial length difference(2.23±1.46)mm in 42 eyes(r=0.782,P<0.01).Conclusion The deprivation form at early stage in congenital cataract patients has no effect on axial length,and its main effect is forming the amblyopia.The anisometropia in single eye with congenital cataract is mainly caused by prolonged ocular axis.