Keraring segments work by remodelling the cornea through the addition technique. The rings' mechanisms of action help in corneal topographical regularization and refractive correction preserving the natural corneal prolate profile. They reduce optical aberrations, improve visual acuity and tolerance to contact lenses. The displacement of the corneal apex to the pupillary centre helps in the stabilization of corneal ectasia thus delaying or preventing corneal transplantation.

Keraring implantation is a simple procedure with a short learning curve, performed under topical anesthesia in an outpatient setting. Because it is a minimally invasive surgical technique, it allows the patient to quickly resume normal activities. Keraring patients report high levels of satisfaction, with positive impacts on their quality of life. Topographic and refractive changes start immediately after implantation and stabilise after 3 months on average.

Keraring AS is the first and only intrastromal ring segment with progressive thickness. It allows for even greater treatment customization options when planning to achieve optimal visual and refractive outcomes for each individual case. It is available in 150^o, 160^o, 180^o, and 330^o arc length, 5mm diameter and the following progressive thicknesses (clockwise and counter-clockwise): 250μm to 350μm, 200μm to 300μm and 150μm to 250μm. The indications for using the Keraring AS are keratoconus, ectasia after LASIK, and irregular astigmatism after transplantation with asymmetric topographical features.

The Keraring Implantation set of surgical instruments are specially designed for intrastromal corneal ring segments implantation. These surgical instruments have been specifically developed for manual and femtosecond laser-assisted techniques. Individual instruments and sets are both available, as well as a sterilization case.