In recent years, cornea specialists have established corneal collagen crosslinking (CXL) as a safe and effective treatment for keratoconus and ectasia patients, but less is known about variants and combination procedures. A new study an Egyptian research team published in Cornea shows the impact of CXL Plus for the correction of the myopic and astigmatic components of keratoconus. CXL Plus combines epithelium-off CXL with topography-guided photorefractive keratectomy (PRK) or intracorneal ring segment implantation, in the same session or sequentially. This particular study combined CXL with topo-guided PRK. The study pointed to various complications and found that CXL Plus reduced the myopic component more than the astigmatic component of keratoconus.
The study, which included 79 eyes of 46 patients, shows CXL Plus can be effective in improving the refractive status in eyes with keratoconus, although a small risk of early postoperative complications was noted. Corneal haze was recorded in 19 eyes (24.1%), one eye developed primary herpes simplex keratitis and one had a persistent epithelial defect. Central corneal stromal opacities were recorded in two eyes (2.5%). Keratoconus progression was seen in five eyes (6.3%), all of which underwent a conventional 30-minute epithelium-off CXL procedure. The most common adverse events were vision-sparing complications related to the epithelium removal: 57 (72.2%) had early postoperative pain, photophobia, lacrimation or foreign body sensation. Epithelial healing was delayed in 11 eyes (13.9%).
The study also noted worse postoperative visual outcomes than baseline in three eyes, two of which were complicated by delayed epithelial healing that led to central corneal opacities, and the third due to a persistent epithelial defect that also led to central corneal opacity.
The authors conclude that, due to these various complications and high rate of postoperative keratoconus progression, “CXL Plus cannot be regarded as a completely safe procedure.”
|Iqbal M, Elmassry A, Tawfik A. Evaluation of the effectiveness of cross-linking combined with photorefractive keratectomy for treatment of Keratoconus. Cornea. 2018;37(9):1143-50.|