A Prospective, Randomized, Double-Masked Controlled Clinical Trial of Postoperative Pain after Transepithelial Photorefractive Keratectomy (Trans-PRK)

OBJECTIVE: To determine the effect of aqua astricta flushing on ocular pain after Trans-PRK. METHOD: Three hundred and seventy eyes from 185 myopic patients were prospectively recruited for the study. Patients underwent Trans-PRK in both eyes. Postsurgically, one eye from each patient was randomly assigned to the trial group, and refrigerated normal saline was used to rinse the eye. The contralateral eye was assigned to the control group, and room temperature normal saline was used to rinse the eye. The primary target was postoperative pain experienced at the end of surgery and on the first, second, and third days after surgery. Secondary targets were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refractive spherical equivalent (MRSE), and haze. RESULTS: Patient pain scores gradually decreased over time, and the difference between time points of all patients was statistically significant (P < 0.05). Postoperative pain was not affected by patient cooperation, education level, refractive SE, optical zone, corneal bed, or cutting depth (P > 0.05). The level of pain at the end of surgery was affected by intraoperative rinsing. The pain level of the aqua astricta group was lower than the normal temperature saline group, and the difference was statistically significant (P < 0.01). Pain scores on the first, second, and third days after surgery were not affected by intraoperative rinse (P > 0.05). CONCLUSION: Trans-PRK is an important means of corneal refractive surgery, but postoperative pain remains unavoidable. These findings suggest that the use of cooled fluid during surgery reduces postoperative pain at the end of surgery.