Changes in Corneal Asphericity after MyoRing Implantation in Moderate and Severe Keratoconus

Abstract

PurposeTo evaluate the effect of MyoRing implantation on corneal asphericity in moderate and severe keratoconus (KCN).MethodsThis cross-sectional observational study comprised 32 eyes of 28 patients with KCN, who had femtosecond-assisted MyoRing corneal implantation. The primary outcome measures were preoperative and six-month postoperative corneal asphericity in 6-, 7-, 8-, 9-, and 10-mm optical zones in the superior, inferior, nasal, temporal, and central areas. The secondary outcome measures included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, thinnest location value, and keratometry readings.ResultsA significant improvement in the UDVA and CDVA was observed six months after the surgery (P < 0.001) with a significant reduction in the spherical (4.67 diopters (D)) and cylindrical (2.19 D) refractive errors. A significant reduction in the corneal asphericity in all the optical zones and in the superior, inferior, nasal, temporal, and central areas was noted (P < 0.001). The mean thickness at the thinnest location of the cornea decreased from 437.15 ± 30.69 to 422.81 ± 36.91 μm. A significant corneal flattening was seen. The K1, K2, and Km changes were 5.32 D, 7 D, and 6.17 D, respectively (P < 0.001).ConclusionMyoRing implantation is effective for improving corneal asphericity in patients with KCN. It allows successful corneal remodeling and provides a significant improvement in UDVA, CDVA, and refractive errors.

Femtosecond Laser and Mechanical Dissection for ICRS and MyoRing Implantation: A Meta-Analysis

“…12 We were able to consider further studies, which were published until April 2020. 9,21,[24][25][26] This metaanalysis demonstrated that all ICRS types and MyoRing showed an improvement in visual, keratometric, and refractive values during the 1-year observation period.…”

Seven-year follow-up of a novel 360-degree implant (annular intracorneal inlay) plus accelerated corneal cross-linking: A case study

“…1 This procedure provides significant biomechanical superiorities compared with ICR implants. 2 In addition, using the femtosecond laser-assisted technique in pocket creation contributes to further precision in creating stromal channels. 8 The combined technique of AICI implantation plus ACXL procedure appears an effective method in managing progressive KCN with notable improvements in CDVA, refractive errors, and topographic findings.…”

“…Previous reports that worked on a full-ring ICR implant as a sole treatment modality in managing KCN patients revealed significant improvements in long-term outcomes of the surgery. 2,4 In practice, a full-ring implant could act as an artificial limbus and reinforce the biomechanics of the ectatic cornea in KCN. 9 This effect is not achieved by segmented ICR implants.…”

“…It is demonstrated that postoperative outcomes could be enhanced by combining a complete full-ring ICR and CXL procedure. 2…”

“…Recent studies have shown the effectiveness of intrastromal corneal ring (ICR) implants and their combination with other treatment modalities in managing KCN patients. [1][2][3] Annular intracorneal inlay (AICI) is a novel continuous 360-degree ICR that could be effective as a sole treatment modality in progressive KCN. 4 The AICI is composed of Hexafocon A material that its biocompatibility was confirmed in an animal study on rabbits.…”