Abstract
Purpose: :
To evaluate postoperative refractive outcomes in patients undergoing phacoemulsification with intraocular lens implantation (Phaco/IOL) after previous corneal refractive surgery.
Methods: :
Retrospective analysis of refractive outcomes for patients undergoing Phaco/IOL after previous corneal refractive surgery from 1997 through 2005, including photorefractive keratectomy (PRK), laser in situ keratomileusis (LASIK), automated lamellar keratoplasty (ALK), hexagonal keratotomy (Hex K) and radial keratotomy (RK). A variety of techniques were used to generate a keratometry (K) value for each IOL power calculation, including manual keratometry, refractive history, contact lens over–refraction, and Videokeratography. The method for choosing an appropriate K value evolved over time; from 1997 though 2002 a single K value was chosen from the available generated K values, while a "consensus K" was derived by averaging the available K values and eliminating outlying values for later cases. Three month postoperative spherical equivalent refractions were determined in all patients and compared to the predicted refractive outcomes provided by the Holladay IOL consultant program. Results were stratified according to year of cataract surgery and by previous refractive surgery technique.
Results: :
Sixty–five eyes from 55 patients were analyzed, including 2 in 1997, 4 in 1998, 1 in 1999, 4 in 2000, 7 in 2001, 8 in 2002, 4 in 2003, 14 in 2004, and 21 in 2005. Average absolute deviations from predicted refraction were 2.5D in 1997, 1.3D in 1998, 1.4D in 1999, 1.2D in 2000, 0.9D in 2001, 0.8D in 2002, 0.5D in 2003, 0.7D in 2004, and 0.8D in 2005. Average absolute deviation was 1.2D for 1997–2002 and 0.7D for 2003–2005 (p =0.04). LASIK was the most common previous refractive surgical procedure (37 eyes), followed by RK (23 eyes), ALK (3 eyes), Hex K (1 eye), and PRK (1 eye). Average absolute deviations from predicted refraction were 1.3D after Hex K, 1.0D after LASIK, 0.9D after ALK, 0.8D after RK, and 0.4D after PRK. There were no significant differences for any of these populations.
Conclusions: :
The number of post–refractive surgery patients requiring cataract extraction continues to increase. Utilizing the "consensus K" method has improved postoperative refractive outcomes in these patients. Previous refractive surgery type did not significantly influence postoperative refractive outcomes.
Keywords: refractive surgery: comparative studies • intraocular lens • refractive surgery: phakic IOL