Abstract
This abstract has been retracted. :
Purpose :
Dry age-related macular degeneration (AMD) is a complex ocular disorder that is thought to result in outer retinal hypoxia and can lead to the growth of choroidal neovascularization. Computational models of dry AMD demonstrate that the presence of drusen and distance between the choroid and retinal photoreceptors affect levels of retinal hypoxia; however, few studies have investigated normobaric hyperoxia treatment for dry AMD. We performed an exploratory study to evaluate the functional and anatomic effects of short-term normobaric hyperoxia in patients with dry AMD. We hypothesized that normobaric hyperoxia would be most effective in retinas with greater separation between the photoreceptors and choriocapillaris.
Methods :
Patients with dry AMD (23 eyes in 18 patients) were categorized based on the presence of: hard drusen (n = 10), drusenoid pigment epithelium detachments (PED) (n = 8) or geographic atrophy (GA) (n = 5). Macular OCT scans and ETDRS visual acuity measurements were obtained before and after 3-hour administration in a blinded fashion of either normobaric hyperoxia (40% FiO2) or normobaric normoxia (20% FiO2).
Results :
Three-hour normobaric hyperoxia treatment in dry AMD patients with drusenoid PED demonstrated significant decreases in foveal volume (-0.003 ± 0.005mm3, p = 0.02) and drusen height (-6.8 ± 7.6 µm, p = 0.002) as well as an increase in visual acuity (LogMAR: -0.06 ± 0.07, p = 0.02) relative to pre-O2 baseline using Two-tailed Student’s dependent samples t-test. These differences were also significant when compared to normobaric normoxia controls using Two-tailed Student’s independent samples t-test. There was a moderate positive correlation between change in drusen height and change in visual acuity in the 3-hour drusenoid PED condition (r2 = 0.42). In contrast, no significant differences in functional and anatomic measures tested were found after three-hour normobaric hyperoxia treatment in patients with hard drusen or geographic atrophy.
Conclusions :
These results support our hypothesis that retinas with larger drusen, resulting in greater separation between the choroid and photoreceptors, respond more to hyperoxia. These findings support the role of hypoxia in AMD and suggest that hyperoxia treatment should be investigated further in these patients.
This is a 2021 ARVO Annual Meeting abstract.