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Updated: May 14, 2026
Retinal Vascular Reactivity as Assessed by Optical Coherence Tomography Angiography
Published on: March 26, 2020
Retinal oxygen metabolism and ocular blood flow in patients with diabetic retinopathy of varying severity
Ahmed M Abu El-Asrar1,2, Abeer A Alhazzani1, Abdulrahman F AlBloushi1
1Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
Purpose:
To investigate blood flow velocity and pulse waveform parameters in the optic nerve head (ONH) and choroid and retinal oxygen metabolism in patients with diabetic retinopathy of varying severity.
Methods:
Retrospective study of 72 patients was analysed. Eyes were categorized according to diabetic retinopathy (DR) severity into mild to moderate non-proliferative diabetic retinopathy (NPDR), severe NPDR and proliferative diabetic retinopathy (PDR). Retinal oximetry and laser speckle flowgraphy measurements were performed.
Results:
Oxygen saturation in retinal arterioles was significantly higher in the PDR group compared to mild to moderate NPDR and severe NPDR groups (p = 0.006 for both comparisons). Oxygen saturation in retinal venules was significantly higher in the PDR group compared to mild to moderate NPDR (p = 0.016) and severe NPDR (p = 0.021) groups. In the ONH, mean blur rate (MBR)-vessel, representing blood flow velocity in the retinal vessels, and MBR-tissue, representing ONH blood flow velocity, were significantly lower in the PDR and severe NPDR groups compared to the mild to moderate NPDR group (p = 0.001; p = 0.041; p = 0.024; p = 0.028, respectively). Among the analysed pulse waveform parameters, flow acceleration index was significantly lower in the PDR group compared to the mild to moderate NPDR group (p = 0.006).
Conclusions:
Our results revealed a link between decreasing retinal and ONH blood flow velocities and increasing retinal arteriolar and venular oxygen saturation with increasing severity of DR.
