Correction of hyperopia and presbyopia by biocompatible filler injection

主题领域：视个人眼睛的解剖结构而定，有不同的屈光不正会限制视力。有31.8%的人患有远视。此外，随着年龄的增长，人体晶状体的调节功能也逐渐丧失。症状通常出现在40岁左右。远视的受累患者继而成为老花眼，在远处既看不见近处也看不见远处。手术远视和老花矫正的现状：矫正远视的手术方法多种多样。不幸的是，这些有相当大的缺点，除了期望的矫正球面等量远视。激光方法只能用于低远视，并伴有频繁的退行、矫正手术/激光手术和干扰光现象，如光晕/眩光和其他高阶像差。人工晶状体导致适应性丧失，由于小远视患者前房狭窄，人工晶状体仅适用于少数患者。目前的角膜植入物只被批准用于低屈光不正或老花眼治疗，而且还会产生像差，从而降低对比灵敏度。目的：通过生物相容性的“角膜填充物”实现对高度屈光不正的远视和老花的稳定矫正。方法：将生物相容性透明粘性填充物注射到一个或多个角膜袋中进行角膜重塑。口袋应该用激光切割。然后用纳米注射器将填充物注入角膜袋。这是通过一个精确切割的角膜隧道来完成的，它通过角膜的形态和形状（类似于白内障的透明角膜隧道）来密封自己。由此产生的角膜前表面变陡和/或后表面变平导致屈光能力的增加，用于矫正远视和老花眼的屈光。一个椭圆形的切割口袋可用于校正散光。通过添加或去除填充材料，折射可以根据需要进行微调。该项目的重要方面将是系统研究屈光矫正的生物力学稳定性和填充材料的生物相容性。

Subject area:Depending on the individual anatomical structure of the eye, there are different refractive errors that can restrict vision. Hyperopia affects 31.8% of the population. In addition the human lens loses its accommodative function with increasing age. Symptoms usual occur around the age of forty. The affected hyperopic patient is then presbyopic and can not see either near or far in the distance.Current state of surgical hyperopia and presbyopia correction:There are various surgical approaches to correct hyperopia. Unfortunately, these have considerable disadvantages in addition to the desired correction of the spherical equivalent of the hyperopia. The laser methods can only be used for low hyperopia and are accompanied by frequent regression, corrective surgical/laser procedures and disturbing light phenomena such as halos/glares and other higher order aberrations. The intraocular lenses lead to a loss of accommodation, the additive implantable lenses are available to only a few patients due to the narrow anterior chamber conditions in small hyperopic eyes. The current corneal implants are only approved for low refractive errors or for presbyopia therapy and also produce aberrations and thus a reduction in contrast sensitivity.Aim:The aim of this work is to achieve a stable hyperopia and presbyopia correction of higher refractive errors through biocompatible "corneal fillers".Methodology:A biocompatible transparent viscous filler is to be injected into one or more corneal pockets for corneal re-shaping. The pocket should be cut with the Femtolaser. The filler is then injected into the corneal pocket with a nano-injector. This is to be done by means of a precisely cut corneal tunnel, which seals itself by the corneal morphology and its shape (analougous to cataract clear corneal tunnels). The resulting steepening of the corneal front surface and / or flattening of its posterior surface cause an increase in the refractive power to be used for the correction of refraction in hyperopia and presbyopia. An oval cutted pocket can be used for the correction of astigmatism. By adding or removing filler material, the refraction can be fine-tuned as required.Important aspects of the project will be systematic studies on the biomechanical stability of the refraction correction and the biocompatibility of filler materials.