Surgery for Obstructive Sleep Apnea Could Reduce Glaucoma Risk

Oxidative stress in patients with obstructive sleep apnea can cause vascular dysregulation and endothelial dysfunction, leading to ocular manifestations including papilledema and normal-tension glaucoma. Fortunately, a preliminary study shows that upper airway surgery may help improve ocular blood flow in these patients, helping to prevent subsequent damage to the optic nerve and macula. This image from the study shows a color-coded composite map, created with laser speckle flowgraphy, describing a quantitative index of blood flow velocity to the optic nerve head.  Photo: Lin PW, et al. Nat Sci Sleep. 2025;17:1249-58. Click image to enlarge. It’s known that obstructive sleep apnea/hypopnea syndrome (OSA) can compromise oxygenation of the optic nerve and potentially lead to glaucomatous optic neuropathy, but what about patients who receive treatment? To investigate, a recent study in Taiwan analyzed optic nerve head microcirculation in patients before and after upper airway surgery, finding that most experienced significant improvement in both OSA severity and ocular blood flow at three months post-op. Its results were published recently in Nature and Science of Sleep.The prospective single-blind study included 29 patients (20 to 70 years old) diagnosed with moderate to severe OSA. The cohort included 25 males and four females, with a mean age of 36.1 years. Before and three months after upper airway surgery, participants underwent overnight polysomnography to measure the apnea-hypopnea index and ophthalmological assessments, including laser speckle flowgraphy (LSFG), to assess microcirculation of the optic nerve head. LSFG measurements were summarized as mean blur rate in all areas, in the big vessel area and in the tissue area of the optic nerve head.The surgery showed high efficacy in reducing the severity of OSA. Several metrics demonstrated significant improvements after surgery: the apnea-hypopnea index score decreased from 47.3 to 28.0, and there was a marked reduction in scores of the Epworth Sleepiness Scale, which lowered from 10.4 to 8.0, suggesting that participants experienced reduced daytime sleepiness following surgery. Mean oxygen saturation levels also rose from 93.7 before surgery to 94.6 at three months post-op.Notably, the LSFG analysis revealed significant improvements in ocular blood flow parameters. After surgery, the mean blur rate in the total area increased from 24.5 to 26.8, and in large vessel areas, this value rose from 52.9 to 58.0. Mean blur rate also improved in tissue areas, from 14.2 to 15.1.Based on these findings, the researchers surmised that “treatment of OSA to increase oxygen supply during sleep can reduce oxidative stress, vascular inflammation, endothelial damage and sympathetic activation, which could be the possible mechanism for improving ocular blood flow and avoiding subsequent damage to optic nerve and macular function.” It would be beneficial to confirm these findings in a future study with a larger sample size, they suggested, as well as to evaluate the longer-term impact of OSA surgery on optic nerve head microcirculation beyond three months.Click here for the journal source. Lin PW, Chiu LW, Chang CT, Lin HC. Alterations on microcirculation of optic nerve head before and after OSA surgery. Nat Sci Sleep. 2025;17:1249-58.