联合应用正负柱镜检影法检测混合散光

The combination of positive cylinders with negative cylinders in the detection of mixed astigmatism

目的 研究联合正、负柱镜检影方法在发现混合散光中临床应用。方法 189例 (340只眼 )混合散光患者随机分为实验组和对照组 ,根据散光度数的大小分为 3个区间 (<3 0 0D、3 0 0～6 0 0D ,>6 0 0D)。其中散光度数 <3 0 0D的 15 6只眼 (试验组 76只眼 ,对照组 80只眼 ) ;3 0 0D～6 0 0D者 132只眼 (试验组 6 8只眼 ,对照组 6 4只眼 ) ;>6 0 0D者 5 3只眼 (试验组 2 9只眼 ,对照组 2 4只眼 )。患者均于睫状肌麻痹后 ,通过正、负柱镜片组合进行检影 ,并用常规的球镜检影法或柱镜检影法作为对照。根据中和影的形态均匀程度、轴位判断的准确性和难易程度、检影时间和镜片组合的数目作综合评价 ,将检影结果分为 3级 ,Ⅰ级 :中和影均匀 ,轴位容易判断 ,检影时间 <5min ,镜片组合的数目 1或 2片 ;Ⅱ级 :中和影欠均匀 ,轴位判断不困难 ,检影时间 5～ 10min ,镜片组合的数目 2或 3片 ;Ⅲ级 :中和影欠均匀 ,易受到干扰 ,轴位判断困难 ,检影时间 >10min ,镜片组合的数目 >3片。结果 散光度数 <3 0 0D时 ,试验组与对照组的检测结果差异无显著意义 (χ2 =0 0 94 ,P =0 75 9)。散光度数为在 3 0 0～ 6 0 0D时 ,试验组与对照组检测结果的差异有显著意义 (χ2 =5 5 4 6 ,P =0 0 19)。散光度数 >6 0 0D时 。

Objective To study clinical retinoscopy combined positive cylinders with negative cylinders in the detection of mixed astigmatisms. Method 189 cases (340 eyes) with mixed astigmatism were divided into three groups (<3.00 D; 3.00～6.00 D;>6.00 D). There are 156 eyes with mixed astigmatism less than 3.00 D (76 eyes in experiment group, 80 eyes in control group); 132 eyes with mixed astigmatism between 3.00 D to 6.00 D (68 eyes in experiment group, 64 eyes in control group) and 53 eyes with mixed astigmatism over 6.00 D (29 eyes in experiment group, 24 eyes in control group). They were examined with cycloplegic retinoscopy. Retinoscopy of combined positive cylinders with negative cylinders was applied in experiment group, while conventional retinoscopy was used in control group. According to the shape of neutralized image, the accuracy and facility of the axis judgement, operating time and the number of combined lens, the result of retinoscopy was classified into three grades. GradeⅠ: The shape of neutralized image is well distributed. The axis is easy to be evaluated precisely. Operating time is less than five minutes and only need one or two piece of lens. GradeⅡ: The shape of neutralized image is not so well distributed. The axis is not difficult to be evaluated. Operating time is from five to ten minutes and needs two or three piece of lens to combine with. Grade Ⅲ:The shape of neutralized image is not so well distributed and would be interfered by the combined lens or other factors easily. The axis is difficult to be evaluated precisely. Operating time is more than ten minutes and needs more than three piece of lens to combine with. Result In the group of mixed astigmatism less than 3.00 D, no significant difference was found between experiment group and control group.(χ 2=0.094, P =0.759). However, significant difference(χ 2=5.546, P =0.019) was found between the groups with mixed astigmatisms from 3.00 D to 6.00 D and very significant difference (χ 2=8.509, P =0.004) was found between the groups with mixed astigmatisms over 6.00 D. Conclusion Retinoscopy of combined positive cylinders with negative cylinders is an effective, convenient and precise method for detection higher degree mixed astigmatisms. It′s an additional assistance for the conventional retinoscopy.