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Evaluation of Capillary and Other Vessel Contribution to Macular Perfusion Density Measured with Optical Coherence Tomography Angiography
Published on: February 18, 2022
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Optical Coherence Tomography Angiography Vessel Density Changes after Acute Intraocular Pressure Elevation
Qi Zhang1, Jost B Jonas1,2, Qian Wang3
1Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China.
Scientific Reports
|April 18, 2018
Summary
Acute intraocular pressure (IOP) elevation did not significantly alter retinal vessel density in the optic nerve head (ONH) or macula. Optical coherence tomography angiography (OCTA) showed stable vasculature, suggesting IOP-related autoregulation of retinal blood flow.
Area of Science:
- Ophthalmology
- Retinal Imaging
- Intraocular Pressure Research
Background:
- Elevated intraocular pressure (IOP) is a risk factor for optic nerve damage.
- Understanding the immediate effects of IOP changes on retinal vasculature is crucial for early detection and management of glaucoma.
- Optical coherence tomography angiography (OCTA) allows for non-invasive visualization of retinal microvasculature.
Purpose of the Study:
- To investigate acute changes in retinal vessel density in the optic nerve head (ONH) and macula following a controlled elevation of IOP.
- To assess the impact of a moderate IOP increase on the papillary and macular vascular networks using OCTA.
Main Methods:
- Prospective observational study involving 40 eyes with qualified OCTA images.
- Intraocular pressure (IOP) was elevated using a 2-hour dark room prone provocative test (DRPPT).
- Retinal vessel density in the ONH and macula was measured by OCTA at baseline and post-DRPPT.
Main Results:
- A mean IOP rise of 9.6 mmHg was observed after DRPPT.
- No significant changes in retinal vessel density were found in the ONH (papillary region) or macula (superficial, deep, outer retinal layers) after IOP elevation (P > 0.05).
- Similar results were observed in a subgroup with IOP rise ≥10 mmHg (mean increase 15.0 mmHg).
Conclusions:
- Acute IOP elevation of 10-15 mmHg for two hours does not significantly alter retinal vessel density in the ONH and macula.
- These findings support the concept of IOP-related autoregulation maintaining retinal blood flow during moderate IOP increases.
- OCTA demonstrates the stability of retinal vasculature under acute IOP challenges.
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