Intrastromal Corneal Ring Segment Implantation by Femtosecond Laser for Keratoconus Correction

Outcome Analysis of Intracorneal Ring Segments for the Treatment of Keratoconus Based on Visual, Refractive, and Aberrometric Impairment

“…[19][20][21] Most of the published studies analyzing the effectiveness of ICRS implantation for the treatment of keratoconus agree that there is a significant flattening of the central cornea after the procedure. [4][5][6][7][8][22][23][24][25] Our results confirm that finding, as we found a statistically significant reduction in the keratometry readings in all grades of keratoconus. We observed that the largest reduction in mean keratometry was found in those cases with the most severe disease.…”

“…These results are consistent with those found in the literature, as most of the studies that have been carried out reported a gain of lines in UDVA. 6,7,10,21,27,28 We observed that the most significant increase in the UDVA was found in patients classified as grade plus, where more than 77% gained 1 or more lines of UDVA. Furthermore, in this group of patients we observed the least number of eyes losing 1 or more lines of UDVA (Tables 6 and 7).…”

“…In the femtosecond laser-assisted surgical procedure the suction ring was applied, and then the disposable glass lens of the laser system was applied first in order to applanate the cornea, fixate the eye, and help maintain a precise distance from the laser head to the focal point. 7 Then, a continuous circular stromal tunnel was created at approximately 80% of corneal depth. The 60-kHz IntraLase femtosecond system was always used (IntraLase Corp, Irvine, California, USA).…”

“…1 A variety of options have been described for the management of this pathologic condition, such as rigid gas-permeable contact lenses, 2 corneal collagen cross-linking, 3 intracorneal ring segment implantation, [4][5][6][7][8][9][10][11] or keratoplasty. 12 In a number of studies intracorneal ring segments (ICRS) have been demonstrated to be effective in improving visual acuity and reducing the refractive error and the mean keratometry in selected cases of keratoconic eyes.…”

“…[4][5][6][7][8][9][10][11] Such a positive therapeutic effect is considered to be based on the induction of a remodeling of the corneal anterior and posterior surface's topography, which improves the optical quality of the cornea and reduces the optical aberrations, with consequent improvement in best-corrected visual acuity. [4][5][6][7][8][9][10][11] Although in the healthy cornea, the sectorial arcuate addition to the corneal local volume caused by these implants at the corneal midperiphery induces a flattening of the central cornea in an arc-shortening effect, with the consequence of a decrease in myopic spherical equivalent attributable to the overall reduction in the optical power of the cornea, 13 such corneal modeling effect may be different in structurally abnormal corneas such as in keratoconus. 14 Even though the effectiveness of ICRS in the correction of keratoconus has been the subject of a number of studies and investigations, most reported evidence is based on the study of limited case series and may reflect only the experience of 1 surgeon or a limited and specific study group.…”