Sequential Intracorneal Ring Segment Implantation and Corneal Transepithelial Collagen Cross-Linking in Keratoconus.

PURPOSE: To assess the clinical outcomes after sequential surgical implantation of intracorneal ring segments and transepithelial corneal collagen cross-linking (TE-CXL) in keratoconic eyes.

METHODS

In this consecutive randomized study, 40 eyes of 29 patients with progressive mild to moderate keratoconus were included and were randomly divided into two groups. Group 1 included 20 eyes that underwent Keraring implantation, and group 2 included 20 eyes that underwent Keraring insertion followed by TE-CXL 1 month later. In both groups, channel creation was performed manually. Visual, refractive, and topographic outcomes were measured preoperatively and 1, 3, and 6 months postoperatively.

RESULTS

There was statistically significant improvement in both groups regarding uncorrected distance visual acuity (P < 0.001) and corrected distance visual acuity (P < 0.001), with a significant reduction in the refractive error and keratometric values (P < 0.001). There was no statistically significant difference between both groups regarding changes in uncorrected distance visual acuity, corrected distance visual acuity, and refractive error (P > 0.05). However, group 2 revealed a more statistically significant reduction in spherical refraction after 3 months (P = 0.04) and highly significant improvement after 6 months (P = 0.004).

CONCLUSIONS

Intracorneal ring segment implantation is an effective procedure for visual and refractive improvement in keratoconic eyes. The addition of TE-CXL to the procedure compensates for residual superficial irregularities, disrupts the progression of the disease, and provides greater improvements in spherical values. The process is simply a deep stretch with superficial lamellar stiffness.