Posters

The influence of cone location on the efficacy of INTACS-SK

Poster Details

First Author: M.Marques PORTUGAL

Co Author(s):    P. Rodrigues   S. Alves   H. Nogueira              

Abstract Details

Purpose:

Keratoconus (KC) can be classified according to the morphology of the cone and the pattern of corneal topography. INTACS-SK are a treatment option for KC and its effectiveness is affected by the severity of the disease and the stage at which the patient is diagnosed and treated. Our purpose is to determine the influence of topographical cone location in the final result of INTACS-SK implantation in keratoconus patients.

Setting:

Instituto de Oftalmologia Dr. Gama Pinto

Methods:

Cases of successful INTACS SK implantation for keratoconus in 2016 and 2017 were studied in terms of pre and post-operative best corrected visual acuity (BCVA), spherical equivalente (SE), astigmatism and topographical elevation maps. 27 eyes from 25 patients were included in the study. INTACS-SK were implanted by the same surgical team following the manufacturer instructions and planning.

Results:

Pre-operatively, BCVA was 0.49±2.03. Topographically, 63% of the cases were classified as paracentral cones (more than 0.6mm from the center of the cornea) and 37% as central cones (less than or equal to 0.6mm from the center of the cornea). Postoperative values were significantly different from pre-operative values. The BCVA was 0.69±0.05 and 0.49±0.07 in the paracentral and central cone´s groups, respectively. When adjusted for pre-operative BCVA, there was a statistically significant difference (p < 0.05) in post-operative BCVA between the two groups using a cut-off value of cone location of 0.6mm from center of the cornea.

Conclusions:

The effectiveness of INTACS-SK depends on an appropriate evaluation of the KC and clear indication for treatment. Our results indicates that paracentral KC - namely those located more than 0.6mm from the center of the cornea - have better results in terms of BCVA. Our study suggests that central cones should be approached differently, either by improvement of surgical techniques ou by managing the patient´s expectations.

Financial Disclosure:

None