- Occur either in the level of subhyaloid space between posterior vitreous face and retina or under internal limiting membrane.
- Localized vitreous gel detachment may occur.
- Horizontal blood level or boat-shaped hemorrhage is usually apparent, which obscures the underlying retina.
- Fluorescein angiography demonstrates blockage of underlying details in areas of hemorrhages.
- Underlying causes include retinal tear, bleeding from neovascularization, rupture of the internal limiting membrane, hypertensive retinopathy, posterior vitreous detachment, and vascular occlusion.