PRÉCIS:Optometrists employing OCT as a routine clinical tool have a higher chance of referring patients for specialist glaucoma management than those without OCT. OBJECTIVE:Timely detection of glaucoma is key to preventing or delaying vision loss. This study aimed to assess whether the routine use of optical coherence tomography (OCT) by optometrists for the detection of glaucomatous changes in the optic nerve and retina increased glaucoma referrals to ophthalmologists. DESIGN:This study was a retrospective review of routinely collected electronic medical records of patients from a chain of 331 optometry practices in Australia. PARTICIPANTS:Electronic medical records were reviewed for every patient aged 18-99 years who attended an included practice between January 1 and July 31, 2019. METHODS:Odds of referral for glaucoma assessment were compared between practices performing OCT routinely on all patients (OCT practices, n=175) and without OCT (non-OCT practices, n=20). A subset of referrals were assessed by ophthalmologists to determine the false positive referral rate. MAIN OUTCOME MEASURES:The primary outcome measure of this study was referral to an ophthalmologist for glaucoma assessment. A secondary outcome was the rate of false positive referrals, analyzed in a subset of patients referred for glaucoma assessment. RESULTS:Records from 994,461 patients (59% female) were included, and 10,475 (1.1%) were referred for glaucoma assessment. Most referrals were associated with normal intraocular pressure (non-OCT practices: n=496, 66%; OCT practices: n=6,603, 68%). Referral for glaucoma was higher in OCT practices (n=9,719, 1.1%) compared with non-OCT practices (n=756, 0.8%, age-adjusted, gender-adjusted, and location-adjusted odds ratio 1.39, 95% confidence interval 1.10-1.76). Of 318 referred patients (3%, all from OCT practices) for whom ophthalmologist feedback was available, 68 (21%) were considered not to have glaucoma. CONCLUSIONS:The routine use of OCT in optometric practice may lead to more timely glaucoma detection and prevention of avoidable vision loss.

Age-related macular degeneration (AMD) is a leading cause of vision loss, the treatment of which may require monthly intravitreal injections. This is a burden on patients and health services, and new delivery modalities that reduce injection frequency are required. To that end, we investigated the suitability of a novel reverse thermoresponsive polymer (RTP) as an ocular drug-delivery vehicle. In this work, we detail the structure and synthesis of a novel RTP, and determine drug release curves for two drugs commonly used in the treatment of AMD, bevacizumab and aflibercept. Biocompatibility of the RTP was assessed in vitro in human and rat cell lines and in vivo following intravitreal injection in rats. Bevacizumab demonstrated a more appropriate release profile than aflibercept, with 67% released within 14 days and 78% released in total over a 183-day period. No toxic effects of RTP were seen in human or rat cells in up to 14 days of co-culture with RTP. Following intravitreal injection, intraocular pressure was unaffected by the presence of RTP and no changes in retinal function or structure were observed at 1 week or 1 month post-injection. RTP injection did not cause inflammation, gliosis or apoptosis in the retina. This work demonstrates the potential suitability of the novel RTP as a sustained-release vehicle for ocular drug delivery for anti-neovascular therapies. Optimization of polymer chemistry for optimal drug loading and release is needed.

Die Tatsache einer möglichen Visus- und Gesichtsfelderholung beim Glaukom ist ein bekanntes, wenn auch bisher wenig erforschtes Phänomen.

Purpose. To use a novel image analysis approach to consider how oxygen saturation changes as a function of vessel width and distance from the nerve and between superior and inferior retinal hemifields.Methods. Ten images were acquired from one eye of 17 participants (mean [standard deviation] age, 28 [4] years; range, 22-38 years) using the Oxymap T1 retinal oximeter. Every pixel identified by the detection algorithm was extracted, and frequency histograms of retinal vessel oxygen saturation were plotted for each vessel diameter (70-170 mu m). Histograms were fitted with two Gaussian models to identify peak arteriole and venule oxygen saturation. Mean (+/- standard error of the mean) arteriole and venule oxygen saturation at each vessel width were calculated. Data were also analyzed in (1) annuli of 100 mu m centered on the optic nerve or (2) upper and lower hemifields demarcated by the center of the optic nerve.Results. Venous oxygen saturation was higher in smaller vessels than in larger vessels. Arterial oxygen saturation remained relatively constant with vessel width. Oxygen saturation was lower in veins nearer the optic nerve. The upper retinal hemisphere showed higher venous oxygen saturation compared with the lower hemifield.Conclusions. The current objective analysis approach provides a more complete picture of retinal oxygen saturation at the posterior pole as a function of vessel width and retinal location.

Purpose To use a novel image analysis approach to consider how oxygen saturation changes as a function of vessel width and distance from the nerve and between superior and inferior retinal hemifields. Methods Ten images were acquired from one eye of 17 participants (mean [standard deviation] age, 28 [4] years; range, 22–38 years) using the Oxymap T1 retinal oximeter. Every pixel identified by the detection algorithm was extracted, and frequency histograms of retinal vessel oxygen saturation were plotted for each vessel diameter (70–170 μm). Histograms were fitted with two Gaussian models to identify peak arteriole and venule oxygen saturation. Mean (±standard error of the mean) arteriole and venule oxygen saturation at each vessel width were calculated. Data were also analyzed in (1) annuli of 100 μm centered on the optic nerve or (2) upper and lower hemifields demarcated by the center of the optic nerve. Results Venous oxygen saturation was higher in smaller vessels than in larger vessels. Arterial oxygen saturation remained relatively constant with vessel width. Oxygen saturation was lower in veins nearer the optic nerve. The upper retinal hemisphere showed higher venous oxygen saturation compared with the lower hemifield. Conclusions The current objective analysis approach provides a more complete picture of retinal oxygen saturation at the posterior pole as a function of vessel width and retinal location.