Epi-Bowman Blunt Keratectomy Versus Diluted EtOH Epithelial Removal in Myopic Photorefractive Keratectomy: A Prospective Contralateral Eye Study

Purpose: To compare the outcomes and complications of Epi-Bowman blunt keratectomy (EBK) using a blunt epikeratome (Epi-Clear, Orca Surgical, Israel), with alcohol delamination of the corneal epithelium during photorefractive keratectomy (PRK) in contralateral eyes. Methods: This prospective, randomized contralateral eye study included 44 eyes of 22 patients undergoing PRK for bilateral myopia or myopic astigmatism. In each patient, epithelial delimitation was performed using an Epi-Clear epikeratome EBK (EBK group) on 1 eye and diluted ethanol (EtOH) on the fellow eye (EtOH group). Postoperative pain, epithelial healing, epithelial profile, and visual outcome were compared between the 2 groups. Results: The mean postoperative pain scores were 0.37 ± 0.25 for the EBK group and 0.82 ± 0.22 for the EtOH group (P = 0.043). The mean epithelial defect size at day 3 postoperatively was 1.61 ± 1.46 and 2.25 ± 1.69 mm2, respectively (P = 0.034). The postoperative 3-month remaining mean spherical equivalent was 0.04 ± 0.49 diopters for the EBK group and 0.21 ± 0.26 D for the EtOH group (P = 0.520). There was no significant difference in UCVA and BCVA between the groups. Conclusions: Our data suggest that this novel EBK device and technique may minimize postoperative pain, accelerate re-epithelialization, and offer earlier visual recovery, compared with EtOH when used for myopic PRK. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved

Holographically written reflective polarisation filter in single-mode optical fibres

A new type of internally written grating filter is proposed and demonstrated in single-mode optical fibers. A photoinduced rocking birefringence is created by polarization interference between two counterpropagating and orthogonal linear-polarization modes at 514.5 nm. This birefringent grating has the correct submicrometer pitch for efficient phase-matched reflection of a linearly polarized mode into the orthogonally polarized counter-propagating mode. The phenomenon represents a new form of holography in which the image (the orthogonal counterpropagating mode) is reconstructed by scattering off a hologram consisting of a periodic birefringence

Holographically written reflective polarisation filter : a new optical fibre grating device

A novel grating device, consisting of a holographically induced birefringence that rocks periodically at half the optical wavelength, is proposed; and its first realisation in photosensitive single-mode fibre reported

Recent Innovations in Collagen Corneal Cross-linking; a Mini Review

The introduction of corneal cross-linking (CXL) with ultraviolet-A (UVA) and Riboflavin photosensitizer (Vit B2) from Seiler et al., revolutionized the treatment of Keratoconus and other corneal ectatic diseases. Today, the commonly known epithelium off Dresden protocol is in clinical use for the last 15 years with great success and regarded by many as the golden standard