What is Vitreous Haemorrhage?
Vitreous haemorrhage refers to blood in the vitreous of the eye that can lead to loss of vision and in severe cases blindness.
What is Vitreous Humour?
Vitreous or vitreous humour is a clear gel-like substance, mainly composed of water, located between the crystalline lens and the retina (light receptive tissue) inside the eye. It fills the centre of the eye (interior of the eyeball) and occupies 2/3 of the volume of the eye giving it the round shape and provides a clear path for the light entering the eye to reach the retina. It is the viscous property of the vitreous that maintains the shape of the eye if compressed.
What are the Symptoms?
The symptoms of vitreous haemorrhage occur all of a sudden and are painless, varying from mild to severe. The most common symptoms are the appearance of floaters (small specks or clouds moving in the field of vision) and blurred vision. Patients often report the perception of shadows, cobwebs and also photophobia (light sensitivity). A mild vitreous haemorrhage is characterized by new multiple floaters; moderate vitreous haemorrhage by dark streaks; and severe vitreous haemorrhage by significant decrease in vision or even blindness.
In some patients, vision is found to be worse in the morning as blood pools at the back of the eye during the night.
What are the Causes of Vitreous Haemorrhage?
There are many causes for vitreous haemorrhage and the mechanisms mainly fall into three categories:
- Growth of abnormal blood vessels: Certain eye disorders like diabetic retinopathy, retinal vein occlusion, retinopathy of prematurity etc., cause the growth of abnormal blood vessels that are fragile, predisposing them to rupture and bleed into the vitreous cavity.
- Damage to normal blood vessels: Blood vessels in the retina can be damaged due to injury or trauma to the eye. Eye disorders such as retinal detachment and retinal vein occlusion can cause damage to the retinal blood vessels and may bleed into the vitreous cavity.
- Bleeding from adjacent parts of the eye: Blood from another source or haemorrhage in other parts of the eye or ocular tumours can cause blood to leak through the internal limiting membrane (layer that separates the retina from the vitreous) into the vitreous cavity.
How is Vitreous Haemorrhage Diagnosed?
Your doctor performs a complete eye examination to diagnose vitreous haemorrhage. Eye drops are instilled, and the pupils are dilated to view the retina and evaluate the cause of haemorrhage. In cases of severe haemorrhage, the doctor examines the eye with ultrasonography to visualize the retina when direct visualization is not possible due to large amounts of blood in the vitreous gel. The cause of haemorrhage may be determined by performing a test called angiography.
What are the Treatment Options For Vitreous Haemorrhage?
Treatment is not considered with mild haemorrhages as they tend to clot and resolve on their own in a few weeks or months. In severe cases, a surgical procedure called a vitrectomy is performed to remove the blood and improve vision and also treat the underlying cause of haemorrhage.