The aim of this study was to evaluate the in vivo effects at 3 years of preservative-free tafluprost on corneal health. It was a prospective, masked, study on consecutive patients with a new prescription of preservative-free (PF) tafluprost (naïve-N or switched-S, 44 and 14 patients), and preserved (P) bimatoprost 0.003% or travoprost 0.004% (P-group, 35 patients). A complete ophthalmic examination and an in vivo corneal confocal microscopy evaluation were performed at baseline and every 6 months for 3 years. Ninety-three patients were enrolled, clinical parameters were similar in the groups at baseline, apart from intraocular pressure (IOP) which was lower in the S-group (p = 0.012). Both at baseline and over time, confocal microscopy parameters had different trends. At baseline, keratocyte activation was similar in the three groups (p = 0.43) but over the next months naïve patients treated with PF-tafluprost presented a significant (p = 0.004) reduction in keratocyte activation. Sub-basal nerves tended to increase in patients switched to PF-tafluprost (p = 0.07) while were stable in the other two groups (p = 0.11 in PF and 0.40 in P group). Grade of tortuosity was stable over time in the three groups. Beading-like formations were stable over time for the P- and the PF-group, while significantly increased in the S-group (p = 0.027). Endothelial density values were statistically different at baseline (p = 0.007), they decreased both in PF-group and in S-group (p = 0.048 and 0.001, respectively), while increased in P-group (p = 0.006). Our study is the first to show that a PF-tafluprost formulation does not significantly alter the corneal structures as examined by confocal microscopy after 36 months of topical daily therapy, while improving corneal alterations due to chronic preserved therapies.
University Eye Clinic, Università degli Studi di Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy. firstname.lastname@example.org.