Sequential intracorneal ring segment implantation followed by transepithelial phototherapeutic keratectomy and corneal cross-linking.

PURPOSE: To evaluate the safety and visual outcomes of intrastromal corneal ring segment (ICRS) implantation followed by transepithelial phototherapeutic keratectomy (te-PTK) and corneal cross-linking (CXL) in patients with mild keratoconus. METHODS: Patients with mild keratoconus and contact lens intolerance who underwent sequential ICRS implantation followed by phototherapeutic keratectomy and corneal CXL between April 2015 and July 2018 were retrospectively included in the study. Refractive and visual outcomes, satisfaction questionnaire and complications were recorded at the last follow-up (mean 9.5 months postoperatively). RESULTS: Twenty eyes of 17 patients were enrolled, including 5 women and 15 men. The mean time between the two procedures was 16 months. Based on values before the first procedure and 9.5 months after the second procedure, significant improvements were noted in uncorrected distance visual acuity (UDVA) (0.80±0.35 logMAR vs. 0.46±0.38 logMAR), corrected distance visual acuity (CDVA) (0.38±0.23 logMAR vs. 0.13±0.16 logMAR), maximal K (56.11±4 diopters [D] vs. 50.6±3.56 D), mean K (51.87±3.43 D vs. 48.45±2.91 D), cylinder (7.99±3.94 D vs. 4.23±3.49 D), and spherical equivalent (-3.84±3.36 D vs. -0.99±2.15 D) (P<0.01). Among the outcomes, we noted 5 (25%) superficial corneal scarring (haze); 75% of eyes gained>=1 logMAR line of CDVA. In all, 94.5% of patients reported that they were satisfied with their outcomes. CONCLUSION: Combining ICRS implantation followed by te-PTK and corneal CXL appears to be a safe and effective approach for improving visual outcomes and quality of life in keratoconus patients.

Long-term outcomes and causes of intrastromal corneal ring segment explantation in a tertiary eye hospital.

PURPOSE: To evaluate the causes and long-term outcomes after intrastromal corneal ring segment (ICRS) explantation in the King Khaled Eye Specialist Hospital. METHODS: This was retrospective cohort study. Two groups were analyzed: Group one, ICRS surgery done in our hospital (n = 41) and group two, surgery done outside but removed in our hospital (n = 29). Causes and postoperative management after ICRS removal were analyzed. For statistical analysis, groups were analyzed into two subgroups of causes of ICRS removal: Visual disturbance versus extrusion/infection/neovascularization (NV) subgroups; and two subgroups of postoperative treatment: Corneal transplant (CT) versus Contact lens (CL)/eyeglasses subgroups. RESULTS: The most common cause of ICRS removal in group one was visual disturbance (45.2%) while in group two was extrusion (41.2%). CL is the preferable management after explantation. 76% of ICRS removal occurred during the first 4 years. In group 1, there was significant worse preimplantation visual acuity (P = 0.02) in CT subgroup versus CL/eyeglasses. CT subgroup had lower pachymetry of 437.4 µm (P = 0.04) and higher myopia of 8.05 (P = 0.03) than CL/eyeglasses subgroup. For group two, there was a significant improvement in uncorrected visual acuity in visual disturbances subgroup after explantation (P = 0.004). After explantation, visual disturbances subgroup had higher myopia -4.4 than extrusion subgroup -1.15 (P = 0.004). CONCLUSION: Seventy-six percent of ICRS removal occurred during the first 4 years. High myopia and pachymetry lower than 437 um were associated with visual disturbances and further management with corneal transplantation. High myopia was also associated with visual disturbances in surgeries done outside our hospital.