早发性近视和迟发性近视张力性调节的比较

Measuring tonic accommodation in early onset myopia and late onset myopia

目的:通过一种测量张力性调节的方法,了解迟发性近视、早发性近视和正视眼的张力性调节表现。探讨张力性调节与近视的相互关系。方法:志愿参加本实验者54例,正视组18例,屈光度(-0.25～+0.50)D之间,早发性近视组18例,平均为(-6.50±2.40)D,迟发性近视组18例,平均为(-3.00±1.75)D。在完全黑暗的环境下,用偏振光游标式调节检测仪对受试者进行张力性调节的测量,比较迟发性近视、早发性近视和正视眼的张力性调节的差异。结果:在缺乏任何视觉刺激的状态下,调节处于一定的静息状态,所有受试者张力性调节的平均值为(0.90±0.76)D。其中正视组的张力性调节平均为(0.80±0.64)D,早发性近视组的张力性调节为(1.32±0.80)D,迟发性近视组的张力性调节平均为(0.62±0.46)D。早发性近视的张力性调节高于正视组和迟发性近视组的张力性调节,差异有非常显著性(P<0.001);正视组和迟发性近视组的张力性调节,差异无显著性(P>0.05)。结论:早发性近视者有较强睫状肌的基础张力水平,易导致牵拉眼球而使近视进展。

AIM： To present a technique for measuring tonic accommodation in late onset myopia, early onset myopia and emmatropia and to investigate the relationship between tonic accommodation and myopia. METHODS： Fifty-four volunteers were enrolled in this study： 18 emmetropia （ - 0. 25 ± 0. 50 D）, 18 early onset myopia [mean RE （ - 6. 50 ± 2.40）D] and 18 late onset myopia [mean RE （ - 3. 00 ± 1.75）D] . Tonic accommodation was measured under dark field conditions using a Polarized Vernier Optometer. RESULTS： Eyes were dark adapted in a resting position in the absence of visual stimulation and showed a mean value of （0. 90 ± 0. 76） D for tonic accommodation. Tonic accommodation for early onset myopia was significantly higher than that for emmatropia and late onset myopia, tonic accommodation was no significantly between late onset myopia and emmatropia. CONCLUSION： Early onset myopia has a greater amount of the oliary muscle tonic level that induces stretch and causes the eyes to become myopia.