Central corneal regularization (CCR): an alternative approach in keratoconus treatment

Abstract

BackgroundTo evaluate the safety and efficacy of an approach that combines corneal customized transepithelial therapeutic ablation to treat irregular corneal optics and accelerated corneal collagen cross-linking (CXL) to strengthen the corneal tissue and stop the progression of keratoconus. The transepithelial therapeutic ablation applied a novel concept named central corneal regularization (CCR) which could correct the corneal morphological irregularities and the eye’s spherocylindrical refractive error with minimal stromal tissue removal.MethodsRetrospective study. Eyes that underwent CCR combined with CXL were evaluated preoperatively and up to 12 months postoperatively for visual acuity, subjective refraction, corneal haze, pachymetry and maximum keratometry (Kmax).ResultsTwenty four eyes of 24 patients with a mean age of 28.92 ± 9.88 years were treated. The mean spherical equivalent (SE) refractive error changed from − 0.74 ± 1.17 D preoperatively to − 1.05 ± 1.52 D at 12 months postoperatively. The mean uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) improved. No eye lost lines of CDVA, 21 had a mean improvement of 3.21 lines. The mean cylinder error and Kmax value dropped from − 3.06 ± 1.83 D and 51.38 ± 3.29 D to − 1.04 ± 0.80 D and 48.70 ± 2.58 D, respectively. The mean haze score at 3, 6 and 12 months was 0.56, 0.19 and 0.06, respectively.ConclusionsCCR combined with CXL offers promising results as a safe and effective treatment in keratoconic patients.

Topography-Guided Trans-Epithelial No-Touch Photorefractive Keratectomy for High Irregular Astigmatism After Penetrating Keratoplasty: A Prospective 12-Months Follow-Up

“…Thereby, granting a constant radial slope to minimize and homogenize the risk of regression in radial direction induced by epithelial regrowth, the observed stability in our cohort may be more solid compared to other PRK techniques. 35 However, a longer follow-up time could report a certain amount of regression in our cohort.…”

Chemically-Boosted Corneal Cross-Linking for the Treatment of Keratoconus through a Riboflavin 0.25% Optimized Solution with High Superoxide Anion Release

“…This preliminary study presents some limitations, such as a low number of eyes and short postoperative follow-up time, so we hope that future studies with larger study cohorts will confirm these preliminary findings since every step forward we take in improving the safety and efficacy of our procedures is positive. After further studies, a possible new scenario of application of this solution could be in CXL plus treatments with sequential and simultaneous Customized Trans-Epithelial No-touch (cTen ® ) photo-ablation, corneal shape remodeling for the reduction of total high order aberrations through a specific customized interactive iVis Technologies proprietary software (CIPTA ® ) [ 61 ].…”

Advances in the diagnosis and treatment of keratoconus

“…Similarly, a protocol in the name of "Central Corneal Regularization (CCR)" on the iVis Suite customized excimer laser ablation treatment platform (iVis Technologies S. r. l., Taranto, Italy) was tried with keratoconus patients (Amsler-Krumeich stage I-II) and was shown to improve both uncorrected and corrected visual acuity. 71,72 A subsequent comparative study also showed that the combination of the CCR/PRK approach with C-CXL results in a more effective reduction in higher-order aberrations and Kmax than what can be achieved with C-CXL alone. 73 Kanellopoulos AJ modified the Athens protocol by incorporating topographically guided varied pattern C-CXL into the protocol thereby reducing the amount of tissue that has to be removed by PRK.…”