近视者持续近距离工作时的调节反应波动

目的 分析不同的屈光度组在持续的近距离工作中调节反应的波动,探讨近视者是否对模糊像有较高的感知阈值;分析持续高水平的调节反应可能是导致近视进展的诱因.方法 41位受试者分为3组,正视组14人,稳定性近视组13人,进展性近视组14人,运用开视野式红外验光仪测量受试者的基础调节反应,并在持续1 h规范近距离工作中,每30 s作调节反应的连续测量.记录个体的基础调节反应值和近距离工作中的调节反应波动曲线,比较不同屈光度组在持续近距离工作中的调节反应波动量.结果 不同屈光度组的调节反应在近距离工作前差异无统计学意义(P>0.05),不同屈光度组在持续近距离工作中的调节反应曲线均呈现出上升,平稳然后再下降的趋势,而进展性近视组在近距离工作的后阶段不能迅速回复到基准值,而是维持在较高的水平.正视组的调节反应对基准值的偏离为(0.0826±0.2410)D,近视稳定组和近视进展组在近距离工作中的调节反应对基准值的偏离分别为(0.1905±0.3619)D和(0.1336±0.3030)D.各组之间的偏离在统计学上无显著的差异,但稳定性近视和进展性近视组的调节反应对基准值的偏离有高于正视组的趋势.有8位受试者在持续近距离工作中出现了调节超前现象,其中近视者占了7位.结论 在持续近距离工作中,调节反应呈现出震荡波动,这在一定程度上能反应感知性焦深或模糊阈值的大小.近视者需要作出更大的波动来引导调节反应跨越其增大的焦深.(中华眼科杂志,2009,45:50-55)

Accommodation response fluctuation in myopia during sustained near work

Objective To analyze the difference of regressive curves during near work among different refractive groups. To analyze if myope have the higher detection threshold for blur image and to see if the high accommodative response is one of the induced factor for myopia progression. Method The accommodation response of emmetrope, stable myope and progressive myope were measured with the open field autorefractor by the 30 seconds interval during 1 hour near work. Drew the progressive curve and compare the fluctuation of accommodation response during the whole near work. Results There were no significant difference of accommodation response among three groups before near work (P>0.05). The fluctuation curve shew rise, calm and then decline trend while progressive myope kept sustaining at high accommodation response level during later period of near work. The discrepancy of stable myope and progressive myope during 1 hour are (0.1905±0.3619)D and (0.1336±0.3030)D respectively. Stable myope and progressive myope had the trend of high deviation than emmetropia. 8 subjects among 41 shew accommodation lead during near work while 7 are myopia. Conclusion Accommodation response shew fluctuation trend during sustained near work, the amplitude of fluctuation could reflect the defocus and the sensitivity threshold for blur image. The stable and progressive myope have the higher defocus so they need greater fluctuation to exceed the defocus. (Chin J Ophthalmol, 2009,45:50-55)