Effect of cycloplegic eye drops on pain after photorefractive keratectomy and corneal collagen cross-linking

Abstract

Purpose The aim of this study was to evaluate the effectiveness of topical cycloplegic eye drops (cyclopentolate) on relieving ocular pain and discomfort after photorefractive keratectomy (PRK) and corneal collagen cross-linking (CXL).Patients and methods This is a randomized controlled double-blind study that included 30 patients eligible for bilateral PRK or CXL. After removal of the corneal epithelium and completion of the procedure, a plano bandage soft contact lens was placed. Postoperative medications were topical prednisolone, moxifloxacin, and tear substitute, each four times/day for both eyes. For each patient, one eye had the cycloplegic drops and the other eye had placebo drops. All the patients were asked to complete three types of pain rating questionnaires: visual analog scale (VAS), verbal rating scale (VRS), and Mac-Gill pain questionnaire (PRI) at each time of postoperative follow-up.Results VAS, VRS, and PRI mean scores at the first postoperative hour did not show any significant difference between cycloplegic and control eyes (P>0.50). However, the cycloplegic eyes had significantly lower mean VAS and PRI scores at 24 and 48 h, postoperatively (P<0.001 and 0.01, respectively). In the first postoperative day, 13.3% of the control eyes had mild pain, 66.7% had moderate pain, and 20% had severe pain, whereas 30.0% of the cycloplegic eyes had mild pain and 70% had moderate pain (0% had severe pain) on the VRS. All cycloplegic eyes had photophobia and blurring of vision during the first three postoperative days, which rapidly improved after cessation of the cycloplegic drops.Conclusion Cycloplegic eye drops (cyclopentolate) were safe and effective in reducing pain and ocular discomfort after removal of the corneal epithelium in PRK and CXL with tolerable side effects, which rapidly improved after cessation of the drops.