1992年Schachar提出巩膜扩张术逆转老视的方法后，其术后调节力增加范围从+1.00～+10.00D的效果报道引起了许多研究者的关注和质疑。Mathews［27］应用动态红外验光仪客观检测了巩膜扩张术前、术后的调节力。该研究对象为：四位接受巩膜扩张术的老视受试者，年龄50～58岁，其中两位记录了术前、术后检测资料，一位记录了术前检测资料，一位记录了术后检测资料；三位年青人作为对照组。研究结果表明，巩膜扩张术不能逆转老视的调节力。Mathews认为，有关部分术后有近阅读改善和无需配戴阅读眼镜能阅读比术前小的字母的报道，要考虑焦深、模糊辨认、记忆以及多焦点效应等因素的影响。若排除上述影响因素之后，经仔细的心理物理学检查仍然表明有近阅读改善现象，则还需进一步研究除外调节力恢复的其他机制。
3 总结和展望
综上所述，Schachar调节假说虽已有一定的实验证据和临床经验，但当前众多研究依然支持Helmholtz调节理论，Schachar调节假说在许多方面尚缺乏足够的客观证据。作为每个人一生中必将经历且将伴随半生的老视，目前主要仍用单光眼镜、双光眼镜和渐变多焦点眼镜来弥补调节力的不足，而多焦点接触镜、多焦点角膜屈光手术及多焦点人工晶状体也渐将成为老视的选择。唯有真正明确调节和老视的机制，才有可能产生新的逆转老视的有效方法。近年来注入式人工晶状体动物实验研究的快速进展有可能为阐明老视机制和老视治疗带来新的突破，但目前仍需克服多聚体注入物的生物相容性、囊袋内多聚体的渗漏性和囊膜下混浊等诸多难题。可以预见，关于老视机制及其治疗的研究将是二十一世纪极具挑战性和最急迫解决的研究课题和前沿领域。
作者简介：倪海龙(1974-)，男，温州乐清人，现为温州医学院眼视光学院硕士研究生。
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