Contact correction of postkeratoplastic ametropia in patients after deep anterior lamellar keratoplasty

Purpose. To conduct a clinical and functional analysis of contact correction of postkeratoplastic ametropia with rigid gas-permeable scleral lenses (RGPSL) in patients after deep anterior lamellar keratoplasty.

Material and methods. Clinical and functional results of correction of postkeratoplastic ametropia with RGPSL were analyzed on the basis of a comprehensive examination of 35 eyes (35 patients) after deep anterior lamellar keratoplasty (DALK) performed for stage III keratoconus. The examination included patients who had low corrected visual acuity with spectacle correction and the corneal suture was removed 1 year or more after deep anterior lamellar keratoplasty. All patients underwent: autorefractokeratometry, visometry, biomicroscopy, computed keratotopography, aberrometry, endothelial cell density calculation, analysis of corneal graft biomechanical properties, optical coherence tomography of the corneal graft. The mean age of the patients was 29 ± 8 years. In all patients, RGPSL was selected on average 1.5 ± 0.85 years after DALK. All RGPSL were from OKVision (OKV-RGP Onefit Med, Canada). The follow-up period was 6 months.

Results. The uncorrected visual acuity was 1.0 ± 1.18 LogMAR, the best corrected visual acuity (BCVA) with glasses was 0.5 ± 0.8 LogMAR, the spherical refractive component was 2.44 ± 2.12 D, the cylindrical refractive component was -6,25 ± 1.24 D. The average value of BCVA in RGPSL increased to 0.72 ± 0.14 (p = 0.0054). The obtained result remained stable during 6 months of observation. In the analysis of corneal aberrations measured with the OPD-Scan II device before and after 6 months after wearing of RGPSL was noted a statistically significant decrease in total corneal aberrations, including higher-order ones. After 6 months of observation, according to Confoscan-4 data was noted the decrease in the density of corneal graft endothelial cells from 2526 ± 332 to 2510 ± 302 cells/mm² (p = 0.0326) and it corresponded to physiological losses.

Conclusions. Clinical and functional analysis of the correction of postkeratoplastic ametropia with rigid gas-permeable scleral lenses during 6 months of follow-up showed high optical efficiency and safety of their use during the entire observation period.

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