Correction of hyperopia and presbyopia by biocompatible filler injection

• Applicant: Dr. Christian Wertheimer
• Subject Area: Ophthalmology
• Term: from 2017 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 386697299

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.

• DFG Programme: Research Fellowships
• International Connection: USA
• Participating Institution: Klinikum der Universität München; Campus Innenstadt; Augenklinik
• Host: Professorin Dr. Irene Kochevar, Ph.D.