A vitreous haemorrhage is a collection of blood within the eye, in the space between the retina and the lens. Normally the vitreous cavity is filled with clear, transparent jelly. Light passes through the vitreous uninterrupted, and is focused on the retina. When bleeding occurs into the vitreous jelly, the light path is blocked and vision is impaired.
Fig 1. Normal retina
Fig 2. Retina obscured by blood due to Vitreous Haemorrhage
What causes a Vitreous Haemorrhage?
A vitreous haemorrhage is usually due to a blood vessel within the retina breaking, and bleeding into the vitreous cavity. Common causes of bleeding are a result of the development of fragile new blood vessels on the retina due to either diabetes or blockages in the retinal veins (Retinal Vein Occlusions).
Another common cause of vitreous haemorrhage is a “Posterior Vitreous Detachment”. This occurs as a result of age changes in the vitreous jelly and results in the jelly peeling off and separating from the retina. As the jelly separates, it can tear the retina or small blood vessels on the surface of the retina.
Other common causes of bleeding are retinal tears and detachments, penetrating or blunt injuries to the eye or inflammatory diseases of the eye
How does a Vitreous Haemorrhage affect vision?
A vitreous haemorrhage can be severe and result in legal blindness, or it may be mild and result only in annoying black floaters. The severity of visual loss is related to the density of the haemorrhage and the underlying cause for the bleeding.
It is important to understand that a vitreous haemorrhage itself usually does not damage the eye or permanently affect the vision. It is the underlying condition, eg diabetes, or vein occlusion which can permanently damage the vision.
What is the treatment for a Vitreous Haemorrhage?
The most important first step is to identify the cause of the vitreous haemorrhage and treat that.
If a vitreous haemorrhage is mild and not affecting your vision, no treatment is required. The floaters may be annoying, but if they are mild it is best to ignore them, and wait for them to decrease with time. In some people with mild haemorrhages, the blood may clear within a few weeks. In people with more severe haemorrhages, the blood may take many months to clear or may not clear at all.
If the blood is not clearing quickly enough, it can be removed surgically. However it is important to weigh up the risks versus benefits carefully, and only proceed if the blood is causing noticeable problems with your vision, or interfering with your day to day activities.
What is vitreous surgery like?
Modern surgery is now very successful in removing the blood and improving vision. The surgical procedure is called a Vitrectomy. This is performed using very fine microsurgical instruments which are inserted inside the eye to remove the vitreous jelly and the blood. The vitreous jelly is replaced with special balanced saline solution or a temporary gas bubble, and these are replaced by your body with it’s own fluids over the weeks after the surgery. The surgery takes approximately one hour, and is not painful. It is performed in a day surgery, and you do not need to stay in hospital over night.
What is the chance of my vision improving after surgery?
There is usually a greater than 90% chance that the vision will improve after surgery. The final amount of visual improvement after surgery depends entirely on the health of the underlying retina. Once the blood is removed, if the underlying retina is normal, the vision should return to the level it was before the bleeding occurred. If the retina has been damaged by diabetes, retinal detachment, macular degeneration or a retinal vein occlusion, the vision may not improve.
What will happen if I do not have the surgery?
If the blood is not removed, it will usually not damage the eye itself. There are exceptions however, where delaying surgery can be detrimental. For example diabetes in the eye can get worse and remain undetected and untreated behind the blood. A retinal detachment can develop and result in permanent visual impairment
What happens after the surgery?
Following surgery, the vision will be blurred for a few weeks due to mild swelling and the dilating eye drops. Some patients who have a gas bubble will see a black, wobbly, horizontal line which will slowly become lower and lower. This is the edge of the gas bubble, and is normal and will go away completely when the bubble is reabsorbed.
Immediately after the surgery, a patch will be placed on your eye with tape. This will be removed the morning after the surgery when you come to the office. After that, there is no need to wear a patch during the day. A protective shield is recommended for sleeping, for the first week after the surgery.
For the first one to two weeks following surgery you need to take it easy. Eye drops need to be used for one to two months following surgery. These should commence the day after surgery, after your have seen your surgeon.
New spectacles may need to be obtained three to four months following surgery.
What if I have a gas bubble?
Your surgeon will tell you if you have a gas bubble placed during surgery. If so, you will need to keep your face down for at least 50-55 minutes in the hour, the other 5-10 minutes may be used to perform normal duties. You need to sleep with your head face down as much as possible. The face down position can be maintained whilst sitting in a chair and keeping one’s head down.
It is extremely important that you do not fly in an airplane until the gas bubble as gone. Doing so will risk extreme increases in intraocular pressure.
By two weeks after the day of surgery, you do not need to be so strict with the face down positioning. It is very important not to sleep on your back, or lie on your back looking up for any extended periods, as in this position, the gas bubble will rub on your lens, which should be avoided.
What are the risks of surgery?
One should be aware that all surgery has risk and occasionally problems can arise following surgery. A cataract may develop earlier than would be expected during the normal aging process. Sometimes cataract surgery is combined with vitrectomy surgery if a cataract is already present at the time the epiretinal membrane is diagnosed. Cataract surgery is a very quick and successful surgery. Occasionally, the eye may develop increased pressure (glaucoma) and medication may be required to control this. Retinal tears or detachment of the retina may develop during surgery, or following surgery, and may require further surgery to correct these. Infection and haemorrhage are very rare risks which may occur with any surgery. Very rarely, if you have a severe infection or severe bleeding you can go blind in the eye. The chance of this occurring is much less than 1 %. If you notice pain or reduced vision following surgery, contact our consulting rooms on 3831 0101 as soon as possible. For after hours emergencies, please contact your surgeon’s mobile number or Princess Alexandra Hospital emergency department
There is a lot of information available on the internet. It is very important however to ensure that the information comes from a reputable source. Unfortunately there are websites with false or misleading information, or websites offering unproven or potentially dangerous treatments. It is strongly recommended to visit only reputable government or university websites.
The following websites are from the world’s leading hospitals or government sponsored reputable research institutions, and the information is of high quality.
The Mayo Clinic
The United States National Eye Institute