Intracorneal Ring Segments for Keratoconus Treatment
Authors: Vinciguerra, R., Fernández-Vega-Cueto, L., Poo-Lopez, A., Eliasy, A., Merayo-Lloves, J., Elsheikh, A., Madrid-Costa, D., Lisa, C., and Alfonso, J.F.
Journal: Journal of Refractive Surgery
Publication Date: Apr 2022
Implanted intracorneal ring segments (ICRS)
Summary:
Keratoconus is an eye condition that causes the cornea to thin and becomes irregularly shaped. One widely accepted treatment for keratoconus is intracorneal ring segments (ICRS) implantation. This technique improves the corneal shape and visual acuity, and it has an excellent safety profile. However, the exact mechanism that interrupts the disease progression has not been fully understood.
Our research aimed to understand the effect of ICRS implantation on the cornea's biomechanics by using an instrument called the Corvis ST. We found that the implantation of ICRS does not significantly change the corneal biomechanical measurements. This indicates that the cornea's behaviour under the air puff used in the examination is not affected by the placement of ICRS.
The study also revealed that the long-term stable visual and refractive outcomes previously reported were not related to an increase in corneal biomechanical properties, like the effect of corneal cross-linking. Instead, the stabilisation of the disease might be due to the redistribution of stresses and changes in the curvature pattern of the cornea.
One notable finding of our research was that all visual and refractive outcomes significantly improved by more than three lines after surgery. This means that our study evaluated corneal biomechanical parameters in a sample of patients who had successful ICRS implantation.
In conclusion, our study shows that ICRS implantation does not affect intraocular pressure (IOP) and corneal biomechanical measurements of the Corvis ST in the early follow-up period. This confirms the possibility of using the Corvis ST to assess long-term corneal biomechanical changes after ICRS implantation and to validate its use for IOP measurement.