Efficacy of Preservative-free Latanoprost in Normal-tension Glaucoma with Mild to Moderate Dry Eye

Purpose: To evaluate the efficacy and safety of preservative-free latanoprost in patients with normal-tension glaucoma who had mild to moderate dry eye after switching from preserved latanoprost. Methods: This retrospective study was conducted in patients with normal-tension glaucoma who had mild to moderate dry eye. All enrolled patients had used preserved latanoprost and switched to preservative-free Latanoprost. The study consisted of a baseline visit (treatment with preserved latanoprost) and four follow-up visits conducted after 1, 3, 6, and 12 months of treatment with preservative-free latanoprost. Intraocular pressure (IOP), mean deviation (MD), ocular surface disease index (OSDI), Shirmer's test score, tear break-up time (TBUT), corneo-conjunctival fluorescein staining, and adverse drug reactions were evaluated. Results: The mean IOP and MD values during treatment with preserved latanoprost were 14.1 +/- 2.6 mmHg and -2.68 +/- 0.11 dB, respectively. The mean IOP and MD values at 12 months after switching to preservative-free latanoprost were 13.9 +/- 1.9 mmHg and -2.66 +/- 0.12 dB, respectively. The OSDI, Shirmer's test score, BUT, and corneo-conjunctival fluorescein staining during treatment with preserved latanoprost were 53.15 +/- 8.86, 4.97 +/- 1.71 mm, 4.92 +/- 1.72 seconds, and 2.92 +/- 1.05, respectively. The OSDI, Shirmer's test score, TBUT, and corneo-conjunctival fluorescein staining at 12 months after switching to preservative-free latanoprost were 49.07 +/- 6.97, 5.51 +/- 1.48 mm, 5.49 +/- 1.46 seconds, and 2.47 +/- 1.09, respectively. There were no serious adverse drug reactions causing ocular damage. Conclusions: Preservative-free latanoprost was effective for improving objective and subjective symptoms compared to preserved latanoprost; it maintained a stable IOP and visual field value in patients with normal-tension glaucoma who had mild to moderate dry eye.