Abstract
Purpose: :
To evaluate the intra-operative, early postoperative, and long-term complications encountered with combined topography-guided photorefractive keratectomy (PRK) and riboflavin/ultraviolet A corneal collagen cross-linking (CXL) (the Athens Protocol).
Methods: :
412 keratoconus (KCN) cases that had undergone the Athens Protocol (combined topography-guided PRK and CXL) were evaluated over a follow-up time of 6 to 48 months. All cases were evaluated for uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), refractive error, keratometry (K), corneal topography (T), pachymetry (P), endothelial cell count (ECC), epithelial stability, and corneal clarity.
Results: :
The complications encountered were delayed epithelial healing, postoperative pain, epithelial scarring, transient stromal haze, and progression of ectasia. Epithelial healing occurred in 75% of the cases by day 4, 15% by day 5, and 10% by day 10. No significant pain on postoperative day 1 was reported in 45% of the cases, moderate pain in 25%, and severe pain in 30%. Salzmann-like epithelial scarring, seen in 25% of the cases, persisted for an average of one month. The epithelial scar resolved with lubrication (30%), lubrication and bandage contact lens (BCL) (25%), autologous serum administration in addition to lubrication and BCL (25%), or surgical removal (20%). At 6 months post-procedure, 12 of the 412 cases had persistent subepithelial corneal scarring, but none that necessitated penetrating keratoplasty. Transient stromal haze was noted in 15% of the cases, which resolved by month 6 in 95% of these cases (8 of 412 cases showed stromal haze past month 6). Seven of 412 cases showed signs of ectatic progression, for which 2 required penetrating keratoplasty, 4 required repeat CXL, and 1 elected no treatment. One case with ectatic progression had undergone pregnancy out of 7 total pregnancies of the 412 cases.
Conclusions: :
The long-term effects of combined topography-guided PRK and CXL demonstrate this treatment to be safe and effective in preventing ectasia in eyes with KCN. The most significant complications were delayed epithelial healing and epithelial scarring that were managed with various methods.
Keywords: refractive surgery • keratoconus • cornea: clinical science