Medina A
Massachusetts Institute Of Technology EE Research Laboratory, Cambridge, MA, USA.
Eye (Lond). 2017 Nov;31(11):1621-1627. doi: 10.1038/eye.2017.123. Epub 2017 Jun 16.
PurposeThe eyeball and, in particular, the cornea deform in vitro by the application of a distending force like other visco-elastic tissue. If the force is large enough, the cornea strains beyond the elastic range, and a permanent deformation occurs. Such permanent strain is referred to as 'plastic' strain. The phenomenon, however, has never been observed or produced on living tissue. This report seeks to demonstrate that the central radius of a patient's cornea can be altered in a controlled manner designed to correct refractive errors.MethodsTo plastically deform the living cornea, we applied a vacuum to the cornea of eight rabbits and five human eyes with a novel device. This device consists of a chamber of 11 mm in diameter. The chamber is radially divided into four interconnected sub-chambers.ResultsHere we show that a strain can be achieved in vivo with a force produced by the application of the specially designed chamber where air is evacuated. An anatomical modification of the cornea of humans and rabbits was achieved. The deformation of the cornea was plastic, and therefore permanent.ConclusionsThe method described here-Pneumatic Keratology- can be used to alter the cornea by non-invasive means. A vacuum chamber with radial openings alters the collagen fibers in the stroma and flattens the cornea. A flatter cornea corrects or reduces myopia.
目的
与其他粘弹性组织一样，眼球尤其是角膜在体外受到扩张力作用时会发生变形。如果力足够大，角膜应变会超出弹性范围，从而发生永久性变形。这种永久性应变被称为“塑性”应变。然而，这种现象从未在活体组织上被观察到或产生过。本报告旨在证明，可以通过一种旨在矫正屈光不正的可控方式改变患者角膜的中央半径。
方法
为使活体角膜发生塑性变形，我们使用一种新型装置对8只兔子和5只人眼的角膜施加真空。该装置由一个直径11毫米的腔室组成。腔室沿径向分为四个相互连通的子腔室。
结果
我们在此表明，通过应用专门设计的抽空空气的腔室产生的力，可以在体内实现应变。实现了对人和兔子角膜的解剖学改变。角膜的变形是塑性的，因此是永久性的。
结论
这里描述的方法——气动角膜塑形术——可用于通过非侵入性手段改变角膜。带有径向开口的真空腔室可改变基质中的胶原纤维并使角膜变平。更扁平的角膜可矫正或减轻近视。
