Journal of Ophthalmic and Vision Research

Published date: May 19 2025

Journal Title: Journal of Ophthalmic and Vision Research

Issue title: ‎Volume 20 - 2025

Pages: 1 - 9

DOI: 10.18502/jovr.v20.15354

Diba Idanidibaidani@gmail.comSchool of Medicine, Shahid Beheshti University of Medical Sciences, Tehran

Seyed Mohammadjavad Mashhadimohammadjavadmashhadi021@gmail.comOphthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran

Hamze Babaeihamzebabaei11@gmail.comOphthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran

Farideh Sharifipoursharifipourf@yahoo.comOphthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran

Ramin Nouriniaramin.retin@gmail.comOphthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran

Bahareh Kheiribahareh.kheiri@gmail.comDepartment of Epidemiology and Biostatistics, Schulich School of Medicine & Dentistry, Western University, Ontario

Arezoo MiraftabiEye Research Center, Five Senses Health Institute, Moheb Kowsar Hospital, School of Medicine, Iran University of Medical Sciences, Tehran

Purpose: To evaluate vascular changes on optical coherence tomography angiography (OCTA) in patients with diabetic macular ischemia (DMI) after systemic normobaric oxygen (NBO) therapy.
Methods: This before–after interventional study included 26 eyes of 26 patients with DMI. Macular OCTA was performed before and after 1 hour of 100% NBO therapy at a flow of 10 L/min delivered by face mask. As primary outcomes, changes in OCTA metrics were evaluated using the paired t-test. Subgroup analyses were performed based on gender. The secondary outcomes included identifying parameters correlated with best-corrected visual acuity (BCVA) and factors associated with improvement in OCTA parameters.
Results: The patients included 15 males and 11 females aged 59.48 ± 9.67 years. Overall, no significant change was observed in retinal thickness; however, there was a significant decrease in retinal thickness among females and a significant increase among males (P < 0.001). The foveal avascular zone (FAZ) decreased significantly from 0.38 ± 0.14 to 0.34 ± 0.12 mm2 (P = 0.035). Superficial capillary plexus vessel density (SCP-VD) and deep capillary plexus vessel density (DCP-VD) at fovea increased from 13.5 ± 6.37 to 14.98 ± 6.33% (P = 0.059) and from 24.61 ± 6.75 to 26.59 ± 6.16% (P = 0.022), respectively. In males, BCVA correlated significantly with baseline DCP parameters but corresponded with none of the SCP parameters. In females, BCVA significantly correlated with pre-O2 DCP-VD of the perifoveal inferior quadrant. Finally, regression analysis did not show any parameter that could predict a favorable response.
Conclusion: Using OCTA, we observed a decrease in FAZ and an increase in DCP-VD at fovea after short-term NBO therapy for patients with DMI.

Keywords: Diabetic Macular Ischemia, Foveal Avascular Zone, Optical Coherence Tomography Angiography, Oxygen Therapy

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