PURPOSE: This study examined the effects of normobaric oxygen in patients diagnosed with either a Central Retinal Vein Occlusion (CRVO) or Branched Retinal Vein Occlusion (BRVO) who had previously undergone treatment via Anti-VEGF or PRP treatment. The investigation looked into the changes in Macular Thickness (MT) and Visual Acuity (VA). METHODS: This pilot study analyzed patient data from Beth Israel Deaconess Medical Center (Boston, MA) that had been diagnosed with Retinal Vein Occlusions. The patients were brought in and given 3 hours of normobaric oxygen via an oxygen concentrator with imaging and vision checked both before and after the therapy. RESULTS: Eighty-eight percent of our patients in this pilot study saw a decrease in macular thickness after 3-hour oxygen therapy. The mean change in Maximal Macular Thickness was a decrease of 7.1% which was statistically significant when compared to healthy eyes (p<0.001). Additionally, 44% of patients saw an increase in visual acuity, the primary measure of vision. Visual acuity showed a statistically significant change when compared to changes in healthy eyes (p=0.015). No statistical significance was found in the testing of contrast sensitivity nor intraocular pressure. CONCLUSION: Our study showed improvement in central macular thickness and quality of life for individuals using noninvasive normobaric hyperoxia as a treatment for retinal vein occlusions. However, further research is needed to improve the impact of the study and a full randomized control trial should be implemented to further understand the potential impacts of a noninvasive normobaric hyperoxia treatment as a means to alleviate symptoms in retinal vein occlusions. In addition, in the future oxygen supplementation in conjunction with periodic injections of Anti- VEGF could be investigated as a treatment regimen with potential benefits beyond individual therapy. / 2020-06-17T00:00:00Z

2021 / Background: Radiation retinopathy is a progressive ocular disease that is a common complication following exposure to ionizing radiation. Despite current treatments, some patients continue to lose vision due to retinal ischemia and retinal edema, necessitating further investigation into therapeutical alternatives. Pilot studies of supplemental oxygen and hyperoxia therapy have recently demonstrated improved outcomes in vision and reduction of symptoms in ocular disorders involving diseases of the retinal vasculature such as diabetic retinopathy and retinal vein occlusion. Hyperbaric oxygen therapy (HBOT) has been reported to improve complications associated with radiation retinopathy, but HBOT poses challenges regarding affordability and availability of hyperbaric chambers. Normobaric hyperoxia (NBH) therapy presents a more cost-effective and accessible alternative that has been successfully shown to ameliorate edema and improve visual outcomes in retinopathies with similar clinical presentations as radiation retinopathy and thus may be an effective treatment for complications due to radiation retinopathy. Objective: In this case study, we investigated whether administration of NBH could reduce retinal edema and improve visual acuity in a patient with retinal edema and vision loss associated with radiation retinopathy. Methods: Three patients with radiation retinopathy were initially screened for NBH treatment. Of those, one patient proceeded with treatment and completed two 3-hour NBH sessions and one 3-hour normobaric normoxia (NBN) session which served as a control. Before and after each session, best corrected distance visual acuity (VA) was assessed using Early Treatment Diabetic Retinopathy Study testing, and retinal thickness was imaged using optical coherence tomography. Retinal thickness measurements were taken at five points along the area of edema and average differences and percent changes in thickness were calculated. A student’s one-tailed t-test was used to analyze statistical significance. Results: Retinal thickness in the area of edema was reduced by an average of 27±7.14 µm with an average percent change in thickness of 4.35±1.01%, and VA improved from 20/63-2 (LogMAR=0.54) to 20/63+1 (0.48) after the first NBH trial. After the second NBH trial, retinal thickness in the area of edema was reduced by an average of 20.2±2.59 µm with an average percent change in thickness of 4.42±0.58%, and VA was improved from 20/50 (0.4) to 20/32-1 (0.22). Following the NBN control session, retinal thickness was reduced by an average of 5.8±0.84 µm and had a percent change of 1.71±0.23% with relatively little change in VA. Retinal thickness was found to be significantly reduced following each NBH trial when compared to NBN measurements (p = 0.001 and 0.0002). Conclusion: In a patient with radiation retinopathy, NBH treatment demonstrated improved outcomes in VA and reduction of retinal edema. Addition of NBH therapy to existing disease management plans may expand the treatment repertoire for patients suffering from radiation retinopathy and lend further support for the use of NBH therapy as a treatment option for additional ophthalmic disorders.

PURPOSE: Age-related macular degeneration (AMD) is a complex, progressive ocular disorder that results in outer retinal ischemia and severe vision loss. Dry AMD, the most common form of AMD, is characterized by the build-up of extracellular drusen deposits, dysfunction of the outer retinal layers and degeneration of photoreceptors. This study aimed to examine the anatomic and physiologic effects of short-term normobaric hyperoxia in patients at different stages of dry AMD. METHODS: Twenty-two eyes from 16 patients diagnosed with dry AMD (11 females, 5 males) were used in this study. Eyes were categorized as having either small drusen or drusenoid pigment epithelial detachments (DPEDs) through optical coherence tomography (OCT) imaging. Eyes associated with small drusen received 3-hours of 40% fraction of inspired oxygen (FiO2) normobaric hyperoxia (NBH), whereas eyes associated with DPEDs received either 3-hour NBH or 3-hours of 20% FiO2 normobaric normoxia (NBN). Visual acuity and OCT images of the macula were taken before and after oxygen treatment. Anatomic outcomes consisted of foveal thickness, foveal volume, macular volume and maximum drusen height; visual acuity was the functional outcome. The relationship between maximum drusen height and visual acuity was then examined to determine if these outcomes were associated. RESULTS: Eyes associated with DPED treated with 3-hour NBH had the largest decreases in foveal thickness, foveal volume, macular volume and maximum drusen height. The macular layers were then divided into inner and outer layers. The outer layers, comprised of Bruch’s membrane, drusen and the retinal pigment epithelium, had significant decreases in anatomic outcomes, whereas the inner layers showed no changes. DPED patients treated with 3-hour NBH also had the largest increase in visual acuity following treatment. There was a significant negative correlation between baseline drusen height and baseline visual acuity. For patients with small drusen treated with 3-hour NBH, there were no significant changes to anatomic or functional outcomes. CONCLUSION: The current study demonstrates the efficacy of short-term administration of normobaric hyperoxia in high-risk dry AMD patients with associated DPEDs. Normobaric hyperoxia appears to be a novel and promising treatment that requires further investigation.