Optical coherence tomography angiography in retinal vein occlusions

Area of Science:

• Ophthalmology
• Vascular Biology
• Medical Imaging

Background:

• Retinal vein occlusion (RVO) is a significant cause of vision loss.
• Understanding vascular changes in RVO is crucial for diagnosis and treatment.
• Optical coherence tomography angiography (OCTA) offers detailed visualization of retinal vasculature.

Purpose of the Study:

• To quantify vascular density in different retinal layers and the choriocapillaris in eyes affected by RVO.
• To compare vascular density between RVO-affected eyes, fellow unaffected eyes, and healthy controls.

Main Methods:

• Optical coherence tomography angiography (OCTA) was used to image retinal vasculature.
• A study group of 48 patients with unilateral RVO and a control group of 17 healthy individuals were examined.
• Vascular density, retinal thickness, choroidal thickness, and foveal avascular zone were analyzed.

Main Results:

• Eyes with RVO showed significantly lower vascular density in superficial and deep retinal layers compared to fellow eyes and controls.
• Choriocapillaris density was reduced, while foveal retinal thickness, subfoveal choroidal thickness, and foveal avascular zone were increased in RVO eyes.
• OCTA identified ischemia in 9 out of 14 RVO eyes also assessed by fluorescein angiography.

Conclusions:

• Unaffected eyes of patients with unilateral RVO exhibit vascular abnormalities in retinal layers compared to healthy individuals.
• OCTA is a valuable tool for detecting subtle vascular changes in RVO.
• These findings highlight the widespread vascular impact of RVO beyond the directly affected eye.