There are three main causes of vitreous haemorrhage:
- Damage to normal blood vessels
- Retinal blood vessels that are damaged through injury or trauma can cause a vitreous haemorrhage. Some eye problems can also cause damage to the blood vessels of the retina, such as retinal tears. A retinal vein occlusion can also cause vitreous haemorrhage, as it blocks the veins that feed the retina, which may then bleed into the vitreous ‘gel’.
- Growth of abnormal blood vessels
Some eye conditions can cause the growth of abnormal blood vessels that bleed into the vitreous ‘gel’ of the eye. The later stages of diabetic retinopathy, some retinal vein occlusions, and occasionally wet AMD can cause abnormal, delicate blood vessels to grow and bleed into the vitreous cavity.
Bleeding from other parts of the eye
Occasionally, blood from another source can cause a vitreous haemorrhage. While it is very rare, a haemorrhage in another part of the eye, or even a tumour, can cause blood to leak through into the vitreous ‘gel’.