Visual outcome and corneal aberrometry after implantation of intracorneal ring segments (INTACS) for keratoconus

Abstract

Abstract Purpose: To analyze corneal aberrometry and visual outcome after implantation of intracorneal ring segments (INTACS) in keratoconus patients. Methods: Corneal aberration was measured in 15 keratoconus eyes pre and post implantation of INTACS. Root Mean Square values (RMS), (Total, RMS for corneal astigmatism and RMS for coma) where recorded for 5, 6 and 7 pupil diameters, and where divided into two groups due to their previous levels of coma and total RMS. Comatic aberration was divided in vertical (Z3‐1) an horizontal (Z3+1) Zernicke Coeficcients. All data was recorded pre‐op and three months after surgery. Best corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), spherical equivalent and astigmatism where also analyzed. Results: We found statistically significant decrease in spherical equivalent (p<0,01) and increase of UCVA (p<0,01). Significant increase (p=0,04) in coma and total RMS in patients with lower previous values for 5 and 6mm and significant decrease in patients with higher previous values for 7mm (p=0,03) Conclusions: INTACS implantation for keratoconus reduces the mean spherical refractive error, increases UCVA and improves keratoconus aberrations for 7mm pupil diameter in patients with previous high levels of coma and total RMS.