Against presbyopia
A group of researchers from the Polytechnic University of Valencia, the University of Valencia and the Aiken Ophthalmology Clinic have developed and evaluated in their laboratories a new implant for the correction of presbyopia – age-related hyperopia. As a result of five years of work, they created the first fully transparent trifocal intra-corneal lens, which will give farsighted people the opportunity to clearly see objects located at different distances: far, medium (computer, mobile devices) and close, without using glasses or contact lenses. According to the authors, the intracorneal implant is fully compatible with laser refractive surgery in patients with nearsightedness and farsightedness, as well as with possible subsequent cataract interventions. In addition, it will not interfere with subsequent retinal examination and even surgical interventions because of its transparency.
The implant consists of a diffraction lens made of biocompatible material. Its thickness is less than 5 microns, so it can be installed in the cornea in a cavity created by a femtosecond laser, without the risk of affecting its structure. There is a microperforation in the lens, which provides the transport of the necessary substances to nourish the cornea. This reduces the risk of rejection after the implant is inserted into the patient's cornea.
In addition, some parameters of the new intracorneal lens can be adapted to the individual characteristics of patients.
Currently, the correction of age-related hyperopia is carried out with the help of glasses, bifocal and progressive contact lenses. There are also surgical methods – multifocal intraocular lenses installed instead of a lens, and intracorneal implants. In the latter case, two types are available: fine-aperture and refractive inserts. The first type expands the depth of focus with which vision is achieved at an average distance, but their light efficiency is low because they are partially opaque. The second type gives clear vision at close and long distances, but insufficient on average, for example, when working with a computer.
The new fully transparent trifocal implant overcomes the disadvantages of its analogues. It was tested using software and then in an artificial eye using an adaptive visual simulator based on optics.
The next step will be to start testing on patients in a non–invasive way - using the aforementioned visual simulator.
Article by W.D.Furlan et al. A new trifocal corneal inlay for presbyopia is published in the journal Scientific Reports.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on the materials of the Universitat Politècnica de València: Against presbyopia.