A Technique Of Multiple Corneal Allogenic Ring Segments (Cairs) Preparation From A Single Corneal Graft: A Case Series

To describe a novel technique for preparing multiple Corneal Allogenic Ring Segments (CAIRS) from a single corneal graft using femtosecond laser (FSL) technology.

Hospital Foundation Adolphe de Rothschild- Noémie de Rothschild institute.

Case series of  10 eyes from 10 patients with keratoconus underwent FS-assisted CAIRS implantation from 4 donor corneas. A preoperative and postoperative examination was done at 1 day, 1 week, and 1 month. Anterior segment OCT and corneal tomography with aberrometric and pachymetric analysis were done at each visit. Visual, refractive and topographic parameters were extracted. The thickness and width of implanted CAIRS were analyzed.

Patients were classified according to keratoconus severity: Group A (maximal keratometry Kmax < 75D) and Group B (Kmax > 75D). At 1 month postoperatively, both groups A and B showed a significant decrease in mean keratometry by 4.78 ± 1.57D and 12.87 ± 4.62D, respectively. Total and higher-order aberrations decreased by 5.66 ± 4.55 and 0.65 ± 1.54 in Group A and by 9.45 ± 9.15 and 0.49 ± 1.39 in Group B, respectively. Corrected distance visual acuity (CDVA) improved by 4.8 ± 1.7 lines in Group A. Visual improvement was not significant in Group B. One eye in group B exhibited acute rejection and required explantation.

multiple FS-assisted CAIRS using a single corneal graft maximizes the utilization of viable corneal tissue. CAIRS is an effective and biocompatible therapeutic alternative, particularly in cases of moderate to advanced keratoconus with Kmax <75D.