The field of
refractive surgery has improved tremendously over the past decades with the advent presbyopia correcting intraocular lenses,
phakic intraocular lenses, and improved laser ablation profiles. For younger patients in need of laser vision correction,
femtosecond laser technology has increased the percentage of people that can have LASIK because of its predictable thin flap creation.
There are, however, several patients who because of thin corneas or activity levels would perform better with surface ablation. While many surgeons changed from PRK to LASEK and then to Epi-LASIK, most studies have shown no direct improvement to the patient in terms of pain control, healing time, or postoperative vision. With the discovery of MMC to reduce haze formation, most surgeons discard of the flap whether removed via Epi-LASIK device or alcohol, essentially bringing us back to PRK.
This begs the question: how can we improve our PRK?
Established surgeons know that PRK has always performed as well as LASIK in the long-term results but are reluctant to perform it secondary to patient discomfort and prolonged blurred vision. Several people have discussed their pearls for improving these factors. Dr. Marguerite McDonald has long advocated the use of oral steroids in her surface ablation patients. She and others may also utilize topical NSAIDs, vitamin C, oral neurontin, or oral narcotics for their patients. One thing that has been used less in recent years, however, is the use of chilled BSS or refrigerated contact lenses.
Several studies (Kitazawa Y, Maekawa E, Sasaki S, Tokoro T, Mochizuki M, Ito S. J Cataract Refract Surg. 1999 Oct;25(10):1349-55. Cooling effect on excimer laser photorefractive keratectomy) (Stein HA, Salim AG, Stein RM, Cheskes A. Corneal cooling and rehydration during photorefractive keratectomy to reduce postoperative corneal haze. J Refract Surg. 1999 Mar-Apr;15(2 Suppl):S232-3) have demonstrated that the use of chilled BSS can decrease post-operative corneal haze, but many surgeons feel it also improves patient comfort.
“I use chilled BSS prior to removal of the epithelium after applying alcohol and then again at the end of the treatment. In addition to cooling the keratocytes and preventing haze, I find it has an analgesic quality that allows my patients to feel comfortable for several hours after treatment,” states Dr. Ajit Nemi, a Atlanta-based refractive surgeon.
Whether cooling the surface temperature of the cornea via chilled BSS or contact lenses, it appears that this modality can offer a significant benefit for all patients undergoing surface ablation.