Objective: To investigate the role of ICRS in halting keratoconus progression in a large sample of patients. Methods: A retrospective, non-comparative, interventional study based on the review of medical records of patients diagnosed with keratoconus who underwent Ferrara corneal ring segment implantation. A retrospective chart analysis study of 123 operated eyes with follow-up ranging from 3 to 16 years (mean 5.3 ± 3.6 years) was performed. This study was carried out at Ocular Surgery Unit, São Paulo, Brazil. All topographic data were obtained from Pentacam (Oculus, Arlington, USA). The same surgeon performed all surgeries, and the Ferrara ICRS nomogram was used for ICRS selection in all cases. Results: Corrected distance visual acuity, keratometry, and topographic astigmatism improved in most cases, with statistical significance. In 42 eyes (53.8%), there was an increase in K1 or K2, and in 36 (46.2%), there was a reduction or maintenance in K1. Considering a difference higher than 1 D, between 3-month post-surgery and final visit (group 3), 32 eyes (41%) showed an increase, and 46 eyes (59%) ended equal or below this value. Conclusion: The implantation of ICRS showed improvement in visual and keratometric indexes. The majority of patients did not increase more than one diopter in keratometric values after ICRS implantation. ICRS may be effective for slowing disease progression, especially in older patients.

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Objectives: To report the evaluation of keratoconus progression after Ferrara intrastromal corneal ring segment implantation. Materials and Methods:In this retrospective study, we evaluated progression in eyes with keratoconus after intrastromal corneal ring segments implant. It was considered progression when the increase of the maximum keratometry was greater than 1 diopter (D) when comparing the first postoperative exam (6 months), and the last exam.Results: There was no progression after the surgery. when comparing the mean maximum keratometry pre-op (46.75D) and the pos op data (46.01D), with statistically significant (p-value: 0.047). An increase of less than 1 D in these patients was also observed.In a descriptive analysis, 41 eyes were studied: 8 eyes had an increase greater than 1 D, 19 eyes had an increase equal or less than 1 D and 14 eyes maintained the initial D or had decreased within the years. Analyzing patients ≤ 21 years, the variation of maximum keratometry between 6 months postoperatively was higher in this group (1.82 D ± 3.11) than in the group with more than 21 years (0.5 D ± 1.27). This data was not statistically significant (p = 0.148). Conclusion:This study showed an evolution of maximum keratometry in the postoperative period of the intrastromal ring surgery.However, this increase in the stipulated time of the study was less than 1 D in the majority of patients.

In this report, we discuss a case of a high myopic patient who underwent mechanical LASIK surgery in 2008 that respected the Randleman criteria for ectasia risk but incurred in a percentual thickness alteration (PTA) over 40%. The patient underwent reoperation in 2016 to correct the residual refractive error with wavefront-guided photorefractive keratectomy. At the time of the first surgery, the concept of PTA did not exist. Currently, a PTA that exceeds 35%–40% correlates with an increased risk of ectasia. We reviewed the literature focusing on the differences between the current rationale for post-LASIK enhancement and the selected strategy at the first reintervention. The purpose of this provocative case report is to emphasize the importance of personalized surgery in reoperations, always aiming for the welfare and best vision for the patient.

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