Collagen copolymer toric phakic intraocular lens for residual myopic astigmatism after intrastromal corneal ring segment implantation and corneal collagen crosslinking in a 3-stage procedure for keratoconus

Abstract

Purpose: To evaluate staged combined treatment for keratoconus with intrastromal corneal ring segment (ICRS) implantation followed by corneal collagen crosslinking (CXL) with riboflavin-ultraviolet-A (UVA) and then toric implantable collagen copolymer phakic intraocular lens (pIOL) implantation.

Setting: Large private ophthalmic hospital system.

Design: Case series.

Methods: Eyes with progressive keratoconus had ICRS implantation, then CXL, and then pIOL implantation (minimum 6 months between procedures).

Results: The study enrolled 14 eyes (9 patients). After the combined treatments, the mean decimal uncorrected distance visual acuity (UDVA) and mean decimal corrected distance visual acuity (CDVA) were significantly improved from 0.01 and 0.14, respectively, preoperatively to 0.44 and 0.57, respectively (P<.0001). The mean manifest refraction spherical equivalent decreased from -16.40 diopters (D) ± 3.56 (SD) (range -11.50 to -22.50 D) to -0.80 ± 1.02 D (range -2.00 to +2.00 D) after the combined treatments (P<.0001). The mean refractive astigmatism decreased from -4.73 ± 1.32 D (range -3.00 to -7.00 D) to -0.96 ± 0.35 D (range -0.50 to -1.50 D) (P<.0001). The mean steep and mean flat keratometry values reduced from 60.57 D and 56.16 D, respectively, to 54.48 D and 53.57 D (P<.0001), respectively. No intraoperative or postoperative complications occurred.

Conclusions: A combined 3-stage-approach keratoconus treatment comprising ICRS implantation followed by CXL and then toric pIOL implantation was effective in improving functional vision and reducing disease progression. Longer term studies are required for further evaluation and comparison with other methods.