Keraring ICRS implantation

Intrastromal corneal ring segment (ICRS) implantation, according to the SA.ANA classification is associated with good refractive and visual outcomes one year after surgery, said Dr Inês Laíns of Portugal.

Dr Laíns discussed her analysis of the one-year visual and refractive outcomes of Keraring ICRS implantation. The procedure was performed using topical anaesthesia and the ring was placed in a tunnel created with a femtosecond laser. Placement of the ICRS was determined according to the SA.ANA classification, which was developed to standardise the choice of the basic types of implant combinations according to the characteristics of the ectasia and to enable meaningful comparisons.

Dr Laíns’ prospective study included 49 consecutive keratoconic eyes with a clinical indication for ICRS: contact lens intolerance, a clear central cornea and pachymetry > 400-450µm. Eyes with K-values >70 D were excluded.

ICRS implantation according to SA.ANA classification was associated with good refractive, visual and topographic at six and 12 months postoperatively. However, subgroup analysis revealed interesting data regarding the relationship between the flattest meridian and the coma axis. Eyes in which the flattest topographic axis was coincident with the coma axis experienced better results than those in which the flattest meridian was non-coincident, or ≥ 30º from the coma axis. Dr Laíns concluded that, “When selecting the implantation axis, it is important to consider not only the topography and cylinder, but also the coma axis and value.”