Overview of vitreous hemorrhage
The vitreous gel occupies approximately 2/3 of the total volume of the eye. Also, it is a transparent, semi-solid, or liquid substance that fills the space between the lens in the front of the eye and the lining of the retina at the back of the eye. Also, there are generally no blood vessels within the vitreous gel. The abnormal blood vessels turn to vitreous gel in a variety of eye diseases, usually diabetic retinopathy. There are many blood vessels around the vitreous gel. Avascular hemorrhage occurs when blood vessels break and bleed in or near the vitreous cavity.
The vitreous humour is a transparent jelly-like substance that makes up 80% of the volume of the eyeball. Supports the geographical shape of the eye, allowing light at the same time. It is made primarily with water but with some collagen and hyaluronic acid. The exterior is made of fine fibers that adhere to the retina in the back and the back of the lens in the front.
Symptoms of vitreous hemorrhage
Symptoms of vitreous hemorrhage vary but generally include painless arbitrary floaters and/or visual damage. Early or light bleeding can be described as floaters, cobwebs, shadows, or redness. More significant bleeding limits visual acuity and visual fields or causes scotoma. Patients often say that morning vision is worse because the macula is covered and blood pools at the back of the eye.
Patients should be asked about their history of trauma, eye surgery, diabetes, sickle cell anaemia, leukaemia, carotid artery disease, and high myopia.
A complete examination includes indirect ophthalmoscopy with scleral depression, gonioscopy to assess angle neovascularization, IOP, and B-scan ultrasound if complete posterior pole vision is blurred by blood. Dilated examination of the contralateral eye can help provide evidence for the aetiology of vitreous hemorrhages, such as proliferative diabetic retinopathy.
The presence of vitreous hemorrhage is not difficult to detect. In the flickering lamp, red blood cells appear at the back of the lens with a slit beam placed “off-axis” and a high-powered microscope. In involuntary bleeding, an examination of the retina can be performed and the location and origin of the vitreous hemorrhage can be determined.
Vitreous hemorrhage in the subhyaloid region is also known as preterite hemorrhage. This bleeding is usually boat-shaped because it becomes trapped in the potential space between the posterior thread and the inner limiting layer and settles as a hyphema. Scattered vitreous bleeding in the body of the vitreous does not have a definite boundary and ranges from a few different red blood cells to total posterior pole opacity.
Causes of vitreous hemorrhage
The most common causes are up to 90% of all cases of vitreous bleeding:
- Bleeding from new abnormal blood vessels that occur in advanced diabetic eye disease.
- Bleeding from tears in the retina caused by vitreous detachment.
- Eye injury (the most common cause in teens).
Bleeding inside the eye can come from:
Abnormal blood vessels grow in the back of the eye due to a lack of oxygen. These are brittle and bleed easily. Conditions in which it is presented:
- Diabetic eye disease (most common cause).
- Macular degeneration
- Retinal vein occlusion.
- Retinopathy with sickle cell anaemia.
- Damage to the back of the eye in most premature babies who receive oxygen in special baby care units.
Damaged normal blood vessels. These can be damaged by:
- Posterior vitreous detachment, which often causes a retinal tear.
- Retinal microaneurysm: inflammatory blood vessels in the retina, usually associated with high blood pressure, atherosclerosis, and smoking.
- A blunt injury, a sudden narrowing of the eye, for example, if hit with a squash ball.
- Penetrating wound – causes bleeding throughout the eye. Penetration injury occurs from high-speed injuries, such as grinding and hammering. They do not always cause severe eye pain.
- Subarachnoid haemorrhage, which increases pressure on the veins in the retina and causes them to bleed.
- Eye surgery, especially if it is done inside the eye.
Blood from the back of the retina reaches the eye. It is the most common cause of vitreous bleeding. The result can be:
- Tumours behind the eye (eye tumours are very rare. The most common type is ocular melanoma).
- The new blood vessels behind the retina are fragile.
Posterior vitreous detachment is usually experienced between the ages of 60 and 80. This is what happens to most of us between that age. This occurs when the vitreous is removed from the retina. This happens very suddenly as the vitreous diminishes with age. It usually has no symptoms. Sometimes posterior vitreous detachment causes retinal bleeding. Sometimes the retina tears when it separates in this case, the bleeding is greater.
Most people experience post-vitreous detachment in their 60s or older, and most people do not have significant vitreous bleeding when this occurs. However, noticeable floaters are very common and can probably be caused by light bleeding.
Vitreous hemorrhage risk factors
This problem is more common in people with medical conditions and injuries that can cause damage to the blood vessels of the eye, such as:
- Diabetic retinopathy
- Retinal tear or detachment
- Posterior vitreous detachment
- Trauma or injury to the eye
- Tumours or bleeding from another part of the body.
Diagnosis of vitreous hemorrhage
The doctor will ask about your symptoms and health history. A physical exam will be done. An eye exam will be done. A slit-lamp will be used to view the back of the eye to look for signs of bleeding. Some people may have an ultrasound instead.
It is possible to find the origin of the bleeding with a slit lamp, although if there is a lot of blood in the vitreous humour it will prevent clear vision, and therefore it is difficult to know what happened. In this case, you may have an ultrasound of the eye. Ultrasound can detect many causes of vitreous bleeding, including posterior vitreous detachment, retinal tears and detachments, tumours, and foreign objects.
Sometimes an angiogram is needed. This test shows the blood vessels in the back of the eye. Helps look for abnormal blood vessels like diabetes. Computed tomography (CT) of the eyes may be helpful if a penetrating injury is suspected.
Treatment of vitreous hemorrhage varies depending on the cause. Treatment objectives:
- Find the source of the bleeding.
- Stop the bleeding.
- Repair any damage to the retina before permanent vision loss.
- Restores normal vision.
Once the source of the bleeding is identified, treatment depends on the cause. It means laser treatment for bleeding vessels and other abnormal vessels and repair of tears in the retina. After this, it is a matter of waiting until the blood clears slowly. This can take several weeks.
You are advised to avoid strenuous activity for at least several days, as it is likely to cause clots and induce new bleeding. It is also recommended that you raise the head of the bed and lie down as this will allow the blood from the eye to drain out of the line of sight, at the base of the eye.
Laser photocoagulation is a common treatment for fragile abnormal vessels. Treating both will stop the bleeding and prevent further bleeding. Laser photocoagulation is also used to repair damage to the retina, including retinal detachments. Anti-VEGF injections are aimed at narrowing the new abnormal vessels that form in the eye. In addition to other treatments such as laser photocoagulation and vitrectomy, they are sometimes used in patients with diabetes to reduce bleeding. Cryotherapy is also used to treat retinal detachment.
What happens if a bleed is not treated?
A hemorrhage can be caused by proliferative retinopathy, a condition in which abnormal new blood vessels grow on the surface of the retina. This is called neovascularization. When left untreated, these new blood vessels grow and spread through the vitreous to the pupil area. This increases pressure on the optic nerve (pressure inside the eye). Damage to the optic nerve is irreversible and can lead to loss of vision. Vitreous hemorrhage bleeding is caused by scar tissue at the back of the eye. It can move the retina away from the back layer of the eye, without separating the retina and without requiring additional treatment to permanently damage vision.
Is vitreous hemorrhage painful?
This is one of the reasons that ophthalmologists are increasingly concerned with raising awareness about this disease. In many cases, a vitreous hemorrhage develops very quickly and painlessly, indicating a medical emergency.
Contact an ophthalmologist or the nearest emergency room immediately if you have symptoms of sudden floaters or cobwebs in the eyes or symptoms of vitreous bleeding, such as a red or shadow effect.
How long does it take for a vitreous hemorrhage to disappear?
How long it takes for bleeding symptoms to clear depends on the cause and severity of the bleeding. Once the source of the bleeding is found, treatment can be done. Minor vitreous hemorrhages can be treated with laser treatment, repairs bleeding vessels and tears in the retina. After the source of the bleeding has been repaired, it can take several weeks for the blood that has collected in the eye to clear.