Wide-field angiography in retinal vein occlusions

Abstract

Background: Retinal vein occlusion (RVO) is the second most common retinal vascular disease after diabetic retinopathy. It can result in significant visual loss from complications like macula edema, retinal and iris neovascularization, and vitreous hemorrhage. Recently, ultra-widefield imaging (UWF) has been developed for posterior pole visualization and has shown to be useful in the evaluation and treatment of RVO.

Main text: Ultra-widefield imaging (UWF) imaging allows for visualization of the retina up to an angle of 200°. This is especially important in detecting peripheral retinal pathologies, especially in retinal conditions such as RVO, where the disease process affects the peripheral as well as central retina. In particular, retinal non-perfusion in RVO is a risk factor for neovascularization. Various techniques, such as ischemic index and stereographic projection, have been described to assess areas of ischemia on UWF images. Retinal non-perfusion has an impact on disease complications, such as macular edema, and retinal and iris neovascularization. Retinal non-perfusion also has implications on disease response, including visual acuity, reduction in retinal edema and treatment burden.

Conclusion: Ultra-widefield imaging (UWF) imaging plays an important role in the assessment and management of RVO, especially in measuring retinal non-perfusion in the peripheries.

Keywords: Fluorescein angiography; Ischemic index; Macular edema; Retinal vein occlusion; Ultrawidefield imaging.

Fig. 1

Ultrawidefield fundus photography of central retinal vein occlusion. The pathology extends beyond the region covered by standard fundus cameras. In particular, sclerosed vessels can be seen in the peripheral retina. Optic disc collaterals are seen

Fig. 2

Ultra-widefield image of a human retina in stereographic projection where both annotated ellipses comprise 110,288 pixels. The area shared by both ellipses A is 3.59 mm². The two ellipses labelled B and C have an area of 30.9 mm² and 17.2 mm² respectively (image courtesy of Jano Van Hemert)

Fig. 3

Ischemic central retinal vein occlusion. a Ultrawidefield fluorescein angiogram showing extensive areas of capillary non-perfusion throughout the posterior pole. b Grading diagram illustrating the regions of perfusion (orange) and ischemia (blue)

Fig. 4

Branch retinal vein occlusion. a Widefield fluorescein angiogram (FA) before treatment, showing a large area of non-perfusion superotemporally (blue). Regions of perfused retina are shaded orange. b Widefield FA performed after treatment. The area of retinal non-perfusion has reduced