Slade Stephen G
Slade & Baker Vision Center, Houston, TX 77027, USA.
Curr Opin Ophthalmol. 2007 Jul;18(4):314-7. doi: 10.1097/ICU.0b013e3281bd88a0.
With a growing body of work that examines the biomechanical response of the cornea following flap creation, a case has developed for creation of flaps that take advantage of the inherent strength of the stromal layers of the cornea. These flaps are thinner (+/-100 microm) and the diameter is based on the maximum ablation zone of the excimer laser. The critical component in this approach is the use of the IntraLase Femtosecond Laser (IntraLase, Irvine, California, USA) as it is the only keratome currently capable of achieving a customized flap.
Concern over the thickness of the corneal flap has led to a resurgence of surface ablation in order to preserve as much corneal tissue as possible. Although surface ablation does offer a higher degree of safety versus laser in situ keratomileusis (LASIK), it does not achieve the same visual results during early postoperative recovery or a high degree of patient satisfaction. New biomechanical studies comparing corneal response to various types of laser refractive procedures demonstrate that corneal flaps created with a femtosecond laser are the most stable.
This review is intended to summarize the primary advantages of a customized corneal flap in LASIK, as well as to review the biomechanics that support this approach.
随着越来越多的研究探讨了角膜瓣制作后角膜的生物力学反应,一种利用角膜基质层固有强度制作角膜瓣的方法应运而生。这些角膜瓣更薄(±100微米),直径基于准分子激光的最大消融区。这种方法的关键组成部分是使用IntraLase飞秒激光(美国加利福尼亚州欧文市的IntraLase公司生产),因为它是目前唯一能够制作定制角膜瓣的角膜刀。
对角膜瓣厚度的担忧导致表面消融术再次兴起,以便尽可能保留更多的角膜组织。虽然与准分子原位角膜磨镶术(LASIK)相比,表面消融术确实具有更高的安全性,但在术后早期恢复过程中,它无法达到相同的视觉效果,患者满意度也不高。新的生物力学研究比较了角膜对各种类型激光屈光手术的反应,结果表明,用飞秒激光制作的角膜瓣最稳定。
本综述旨在总结LASIK中定制角膜瓣的主要优点,并回顾支持这种方法的生物力学原理。