Vitreous Hemorrhage: Causes, Treatment, and Recovery
Understanding Vitreous Hemorrhage
The vitreous is a clear, gel-like substance that fills the back portion of the eye. It makes up the majority of the eye's total volume. This clear gel allows light to pass through the eye and reach the retina, which is the light-sensitive tissue at the back of the eye.
Blood can enter the vitreous cavity through three main pathways. Normal blood vessels on or near the retina can rupture when the vitreous gel pulls on them. Abnormal blood vessels that have grown in response to disease can break and bleed. Blood from nearby structures can also seep into the vitreous space.
In conditions like diabetic retinopathy, the retina does not receive enough oxygen. This triggers the release of vascular endothelial growth factor, or VEGF. VEGF is a protein that stimulates the growth of new blood vessels. These new vessels are fragile and lack the tight cell connections found in healthy vessels. They bleed easily and often without warning.
When blood enters the vitreous, it forms small clots. Over time, the body slowly absorbs the blood. A significant hemorrhage can take weeks or even months to clear on its own. During this time, the blood blocks or scatters light, reducing vision. The eye's natural clearing process produces very little inflammation, which helps limit additional damage to the retina.
Who Is Affected and Risk Factors
Vitreous hemorrhage affects roughly 7 out of every 100,000 people each year in the United States (AAO, 2023). It can happen at any age, though the causes tend to differ between younger and older adults. It is one of the most common reasons for sudden vision loss.
Proliferative diabetic retinopathy is the leading cause of vitreous hemorrhage in adults, accounting for 31.5 to 54 percent of all cases (Medscape, 2023). In this condition, chronic high blood sugar damages the retinal blood vessels. The eye responds by growing new, fragile blood vessels that are prone to bleeding. Poor blood sugar control significantly increases this risk.
As people age, the vitreous gel naturally shrinks and pulls away from the retina. This process is called posterior vitreous detachment, or PVD. It becomes more common after age 60. When the vitreous separates, it can tug on retinal blood vessels and cause them to bleed. PVD-related vitreous hemorrhage carries a high risk of a concurrent retinal tear or break (AAO, 2023).
Eye trauma is the leading cause of vitreous hemorrhage in people under 40. Males are at higher risk in this category. Other conditions that can cause vitreous hemorrhage include:
- Retinal vein occlusion (a blockage in the veins draining the retina)
- Sickle cell disease, particularly in Black populations
- Age-related macular degeneration with abnormal blood vessel growth
- High myopia (severe nearsightedness)
- Retinopathy of prematurity in infants
Several additional factors can increase the risk of vitreous hemorrhage or make bleeding worse. Previous cataract surgery can change the structure of the vitreous and increase the chance of PVD. Use of blood thinners or bleeding disorders may make existing bleeding more severe. Hypertension and atherosclerosis can weaken blood vessel walls over time.
Signs and Symptoms
The hallmark of vitreous hemorrhage is sudden, painless vision loss in one eye. The severity depends on how much blood enters the vitreous. A small amount of bleeding may cause a few new floaters or a slight haze. A large hemorrhage can reduce vision to the point where a person can only see light or hand motion.
Many people first notice new floaters that look like cobwebs, dark streaks, or tiny spots drifting across their field of vision. Some describe a reddish or brownish tint to their vision. Vision may be worse in the morning because blood settles over the macula during sleep. As the person sits upright during the day, blood may shift and vision may partially improve.
Flashes of light often accompany floaters when the vitreous is pulling on the retina. This combination can indicate a retinal tear or detachment. A shadow or curtain closing in from the side of the visual field is a warning sign of retinal detachment. See a retina specialist or go to the emergency room immediately if you notice a shadow or curtain effect, flashes of light, or a sudden flood of new floaters.
Diagnosis and Testing
A retina specialist will begin with a dilated eye exam to look for blood in the vitreous and assess the retina. The doctor uses a special microscope and lens to view the inside of the eye. In mild hemorrhages, the retina may still be visible. In dense hemorrhages, the blood blocks the view of the retina entirely.
When the hemorrhage is too dense to see through, a B-scan ultrasound is performed. This painless imaging test uses sound waves to create a picture of the structures inside the eye. It can reveal whether the retina is still attached, whether there is a retinal tear, and whether there are signs of a tumor or other abnormality. B-scan ultrasonography is a critical tool when the retina cannot be directly examined.
In cases of mild to moderate hemorrhage, advanced imaging can provide additional detail. Optical coherence tomography, or OCT, produces detailed cross-sectional images of the retina. Widefield imaging systems can capture photographs of the retina's periphery. These technologies help retina specialists identify the underlying cause and plan treatment.
If the cause of the hemorrhage is not immediately clear, the retina specialist may recommend blood tests. These can check for diabetes, blood clotting disorders, or sickle cell disease. A thorough medical history helps identify risk factors such as hypertension, use of blood thinners, or previous eye surgery.
Treatment Options
For mild hemorrhages without underlying retinal damage, a retina specialist may recommend watchful waiting. Small bleeds may resolve on their own over several weeks as the body absorbs the blood. The specialist will schedule regular follow-up exams to monitor clearing and check for retinal complications. Patients are typically asked to keep their head elevated to encourage blood to settle away from the central visual axis.
For vitreous hemorrhage caused by proliferative diabetic retinopathy, intravitreal anti-VEGF injections can be effective. These medications block vascular endothelial growth factor. Common options include Eylea (aflibercept), Lucentis (ranibizumab), and Avastin (bevacizumab), which is FDA-approved for cancer and used off-label for eye conditions.
The DRCR Retina Network Protocol AB study found that intravitreal aflibercept was comparable to surgery combined with laser treatment at 24 weeks for diabetic vitreous hemorrhage (DRCR Retina Network, 2021). Surgery led to faster initial visual recovery. Anti-VEGF injections are given directly into the eye and may be repeated every 4 to 8 weeks.
Pars plana vitrectomy is a surgery to remove the vitreous gel, along with the blood, from inside the eye. A retina specialist performs this procedure using tiny instruments inserted through small openings in the white of the eye. Modern small-gauge vitrectomy systems have reduced surgical trauma and shortened recovery time.
Vitrectomy is recommended when the hemorrhage does not clear on its own or when blood is too dense to allow examination of the retina. It is also needed when the hemorrhage is accompanied by retinal detachment. During surgery, the specialist can repair retinal tears, remove scar tissue, and apply laser treatment.
When a retinal tear or break is identified, laser photocoagulation (a thermal laser that seals the retina) or cryopexy (a freezing treatment) is used. These treatments prevent the tear from progressing to a retinal detachment. In diabetic cases, panretinal photocoagulation may be applied to reduce abnormal blood vessel growth. These treatments can be performed during vitrectomy or as standalone procedures.
What to Expect
Recovery depends on the cause and severity of the hemorrhage and the treatment approach. With observation alone, a mild hemorrhage may clear over several weeks to a few months. After vitrectomy, many patients notice significant improvement within the first few weeks. The DRCR Retina Network study found that vitrectomy provided faster early visual improvement compared to anti-VEGF injections alone (DRCR Retina Network, 2021).
After vitrectomy, a retina specialist may instruct the patient to maintain a specific head position for several days. This is needed if a gas bubble was placed inside the eye. Activity restrictions, including avoiding heavy lifting and strenuous exercise, are typically in place for a few weeks. Follow-up visits are scheduled frequently in the early recovery period.
For patients being treated with observation or anti-VEGF injections alone, regular monitoring appointments are essential. The specialist will check whether the blood is clearing and whether further treatment is needed.
If left untreated, persistent vitreous hemorrhage can lead to several complications. Ghost cell glaucoma can occur when old red blood cells clog the eye's drainage system and raise eye pressure. Iron released from blood cells can cause toxicity to retinal tissue over time. Recurrent hemorrhage is possible if the underlying cause is not treated. The most serious complication is retinal detachment, which requires urgent surgical repair.
Living with Vitreous Hemorrhage
Because diabetes is the most common cause of vitreous hemorrhage in adults, managing blood sugar is one of the most important steps for prevention. Working with a primary care doctor or endocrinologist to maintain good glycemic control, blood pressure, and cholesterol supports long-term eye health. Patients with sickle cell disease, retinal vein occlusion, or other contributing conditions should work with their medical teams as well.
Patients who have had one episode of vitreous hemorrhage are at increased risk for future episodes. Regular dilated eye exams with a retina specialist are important for early detection. Diabetic patients should follow recommended screening schedules, typically at least once per year or more often if diabetic retinopathy is present.
While recovering from vitreous hemorrhage, patients may need to make temporary adjustments. Driving may not be safe until vision has sufficiently recovered. Reading and close work may be difficult depending on the location and density of the hemorrhage. A retina specialist can provide guidance on when it is safe to resume specific activities.
When to See a Retina Specialist
Certain symptoms require immediate evaluation by a retina specialist or a visit to the emergency room. Do not delay if you experience any of the following:
- Sudden painless vision loss or a significant drop in vision
- A sudden increase in floaters, especially cobwebs, dark streaks, or shadows
- Flashes of light, particularly when accompanied by new floaters
- A shadow or curtain moving across your field of vision
- A red or brownish hue to your vision
People with diabetes should pay close attention to any sudden vision changes. They represent the largest group affected by vitreous hemorrhage. Those with a history of retinal tears, retinal detachment, sickle cell disease, or retinal vein occlusion should also seek prompt evaluation. If you take blood-thinning medications and experience a sudden change in vision, contact a retina specialist the same day.
Early diagnosis is critical because vitreous hemorrhage can mask serious underlying problems. These include retinal detachment or a retinal tear. A same-day or next-day evaluation allows for accurate diagnosis, appropriate imaging, and timely treatment. Delays in care can allow a treatable retinal tear to progress to a full retinal detachment, which is more difficult to repair and can lead to lasting vision loss.
Questions and Answers
Yes. Vitreous hemorrhage can recur, especially if the underlying cause is not fully treated. Patients with proliferative diabetic retinopathy may experience repeated episodes if abnormal blood vessels continue to grow. Treating the underlying condition with anti-VEGF injections, laser therapy, or surgery significantly reduces the chance of recurrence.
The timeline varies depending on the severity of the bleeding and the treatment approach. A mild hemorrhage managed with observation may take several weeks to a few months to clear. After vitrectomy surgery, many patients see meaningful improvement within the first few weeks. Final visual outcomes depend on whether the retina was damaged by the hemorrhage or its underlying cause.
Vitreous hemorrhage itself does not cause lasting vision loss in most cases, as the blood can be cleared naturally or surgically. However, the condition that caused the bleeding may damage the retina. A retinal detachment, severe diabetic retinopathy, or prolonged hemorrhage with iron toxicity can lead to significant vision problems. This is why prompt evaluation and treatment of the underlying cause are so important.
Physical activity guidelines depend on the severity of the hemorrhage and whether surgery has been performed. Strenuous exercise and heavy lifting are generally discouraged during active bleeding and early recovery after vitrectomy. Air travel is usually fine unless a gas bubble has been placed in the eye during surgery. A retina specialist can provide specific activity recommendations based on your condition.
Do not stop any medication without consulting both your retina specialist and your prescribing doctor. Blood thinners can make bleeding more prolonged, but they are often prescribed for serious conditions like heart disease or stroke prevention. Your retina specialist and primary care doctor or cardiologist should work together to balance your eye health with your overall medical needs.