There were 140 eyes in this study that showed a statistical difference in pain scores 24 hours after surgery.3 That difference went away 48 hours after surgery. The eyes which received the diclofenac had less pain than those which received the placebo.3
In a study comparing diclofenac 0.1 percent and ketorolac 0.5 percent (Acular, Allergan), Hong et al found both were effective in reducing post-operative pain. He also found no significant difference between the two NSAIDS.4
PRK treatment options
PRK can go by many different names, including advanced surface ablation (ASA), laser epithelial keratomileusis (LASEK), epi-LASIK, and others. These are various means of removing the epithelium in hopes of improved healing time and reduced postoperative pain.
Einollahi et al found events with mechanical removal of epithelium, rather than using alcohol, and no difference in pain. Chayet and Schanzlin found less postoperative pain with PRK than epi-LASIK (epithelium removed with an epitome).5,6 There does not appear to be a difference in postoperative pain based on how the epithelium is removed—but pain is improved when it is completely removed.7
A bandage contact lens has been significant in lowering postoperative pain following PRK.8 The lens is applied immediately after the procedure and should not be removed until the epithelium is healed.
In a 2014 study, patients having PRK were randomly assigned postoperatively to a senofilcon A (Acuvue Oasys, Johnson & Johnson Vision Care), balafilcon A (PureVision, Bausch + Lomb), or lotrafilcon A (Air Optix, Alcon) bandage contact lens in each eye.9 The senofilcon A lens caused the least pain.
In two separate studies, Air Optix Night & Day (Alcon) yielded less postoperative pain when compared to CooperVision Proclear, a phosphorylcholine contact lens,10 and less postoperative pain when compared to Acuvue Oasys in a 2005 study of 100 eyes.11 These studies were conducted by the United States Army and Navy, respectively—who originally performed only PRK on their patients.
Related: Why I recommend PRK
Oral analgesics are often prescribed postoperatively for PRK patients with variable success. Ibuprofen and acetaminophen have been used independently and in combination. Time-release oral diclofenac (Voltaren-XR, Novartis) has been shown to be superior in a study of 33 PRK patients.12 Opioids of varying strength and combination are often used during the healing of the corneal epithelium, but their effect on the patient’s mental status and alertness may be as significant as their effect on corneal pain.