Alternative Surgical Techniques: Bowman’s Layer Transplantation and Stromal Regenerating Techniques

Keratoconus is a corneal ectatic disease characterized by progressive central or paracentral protrusion and thinning of the cornea leading to myopia and irregular astigmatism. In advanced, progressive cases when other treatments have failed or are contraindicated, Bowman’s layer transplantation can reshape corneal curvature by a flattening effect, stabilizing the cornea long term to prevent further visual loss and avoid or delay corneal transplantation. Stromal regeneration through implantation of decellularized human stromal laminas, with or without cell therapy, could be an encouraging new approach to restore corneal thickness, shape, and transparency in advanced keratoconus. Laser crescent keratectomy may be an alternative approach to intrastromal corneal ring segments to reshape corneal curvature, decreasing high-order aberrations, refractive error, and anterior chamber depth.