Ahmed M Bata1, Klemens Fondi1, Stephan Szegedi1, Gerold C Aschinger2, Anton Hommer1,3, Doreen Schmidl1, Jacqueline Chua4,5, René M Werkmeister2, Gerhard Garhöfer1, Leopold Schmetterer1,2,4,5,6. 1. Department of Clinical Pharmacology, Medical University of Vienna, Austria. 2. Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria. 3. Department of Ophthalmology, Sanatorium Hera, Vienna, Austria. 4. Singapore Eye Research Institute, Singapore National Eye Centre, Singapore. 5. Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore. 6. Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.
Abstract
Purpose: To investigate the age-dependence of total retinal blood flow and total retinal oxygen extraction in healthy subjects and determine their possible correlations with structural optical coherence tomography (OCT) parameters. Methods: This observational cross-sectional study consisted of 68 healthy subjects (mean ± SD age, 45.6 ± 16.3 years; 47% female). Total retinal oxygen extraction was calculated based on measurement of total retinal blood flow using bi-directional Doppler OCT and measurement of oxygen saturation using spectroscopic reflectometry. Retinal nerve fiber layer thickness was measured using OCT, and the total number of retinal ganglion cells was estimated based on a previous published model. Correlation of these parameters with age was studied and the association between structural OCT parameters and hemodynamic vascular parameters was calculated. Results: Both structural and vascular parameters showed a significant decline with increasing age. The correlation coefficients were between r = -0.25 and r = -0.41. Furthermore, structural and vascular parameters were significantly correlated with each other. The strongest association was found between the level of total retinal oxygen extraction and the number of retinal ganglion cells (r = 0.75, P < 0.001). Conclusions: We showed that there was an age-related decline of retinal oxygen extraction. Levels of retinal oxygen extraction are correlated to retinal nerve fiber layer thickness and number of retinal ganglion cells. Our data partially explain the wide inter-individual variability in retinal blood flow values in healthy subjects. Longitudinal studies are required to study the time course of vascular and neuronal loss in humans.
Purpose: To investigate the age-dependence of total retinal blood flow and total retinal oxygen extraction in healthy subjects and determine their possible correlations with structural optical coherence tomography (OCT) parameters. Methods: This observational cross-sectional study consisted of 68 healthy subjects (mean ± SD age, 45.6 ± 16.3 years; 47% female). Total retinal oxygen extraction was calculated based on measurement of total retinal blood flow using bi-directional Doppler OCT and measurement of oxygen saturation using spectroscopic reflectometry. Retinal nerve fiber layer thickness was measured using OCT, and the total number of retinal ganglion cells was estimated based on a previous published model. Correlation of these parameters with age was studied and the association between structural OCT parameters and hemodynamic vascular parameters was calculated. Results: Both structural and vascular parameters showed a significant decline with increasing age. The correlation coefficients were between r = -0.25 and r = -0.41. Furthermore, structural and vascular parameters were significantly correlated with each other. The strongest association was found between the level of total retinal oxygen extraction and the number of retinal ganglion cells (r = 0.75, P < 0.001). Conclusions: We showed that there was an age-related decline of retinal oxygen extraction. Levels of retinal oxygen extraction are correlated to retinal nerve fiber layer thickness and number of retinal ganglion cells. Our data partially explain the wide inter-individual variability in retinal blood flow values in healthy subjects. Longitudinal studies are required to study the time course of vascular and neuronal loss in humans.
Authors: Kristine A Tsantilas; Whitney M Cleghorn; Celia M Bisbach; Jeremy A Whitson; Daniel T Hass; Brian M Robbings; Martin Sadilek; Jonathan D Linton; Austin M Rountree; Ana P Valencia; Mariya T Sweetwyne; Matthew D Campbell; Huiliang Zhang; Connor S R Jankowski; Ian R Sweet; David J Marcinek; Peter S Rabinovitch; James B Hurley Journal: Invest Ophthalmol Vis Sci Date: 2021-11-01 Impact factor: 4.925
Authors: Gerhard Garhöfer; Ahmed M Bata; Alina Popa-Cherecheanu; Anton Hommer; Clemens Vass; Hemma Resch; Doreen Schmidl; René M Werkmeister; Leopold Schmetterer Journal: Int J Mol Sci Date: 2022-09-05 Impact factor: 6.208
Authors: Stephan Szegedi; Peter Dal-Bianco; Elisabeth Stögmann; Tatjana Traub-Weidinger; Michael Rainer; Andreas Masching; Doreen Schmidl; René M Werkmeister; Jacqueline Chua; Leopold Schmetterer; Gerhard Garhöfer Journal: Acta Ophthalmol Date: 2020-03-25 Impact factor: 3.761
Authors: Stephan Szegedi; Nikolaus Hommer; Martin Kallab; Stefan Puchner; Doreen Schmidl; René M Werkmeister; Gerhard Garhöfer; Leopold Schmetterer Journal: Transl Vis Sci Technol Date: 2020-06-25 Impact factor: 3.283
Authors: Mozhgan Sharifizad; Doreen Schmidl; René M Werkmeister; Harald Zeisler; Reinhard Told; Julia Binder; Lorenz Küssel; Gerhard Garhöfer; Leopold Schmetterer Journal: Acta Ophthalmol Date: 2020-12-16 Impact factor: 3.761