Retinal vein occlusion (RVO) is a condition affecting the blood vessels in your eye’s retina, the light-sensitive tissue at the back of the eye. It occurs when a vein in the retina becomes blocked, leading to impaired blood flow and potential vision problems. This guide will help you understand RVO, its types, symptoms, causes, diagnosis, treatment options, and living with the condition.
Types of Retinal Vein Occlusion
There are two main types of RVO:
1. Central Retinal Vein Occlusion (CRVO): This occurs when the main vein draining blood from the retina (central retinal vein) becomes blocked.
2. Branch Retinal Vein Occlusion (BRVO): This happens when one of the smaller branch veins in the retina becomes occluded.
A less common type is Hemiretinal Vein Occlusion (HRVO), which affects half of the retina.
Symptoms
RVO often presents as a sudden, painless loss of vision in one eye. Other symptoms may include:
· Blurry or distorted vision
· Dark areas or blind spots in your vision
· Floaters (dark spots or squiggles in your vision)
· In severe cases, eye pain or redness
It’s important to note that symptoms can vary depending on the severity and location of the blockage.
Causes and Risk Factors
RVO is typically caused by a blood clot forming in the retinal vein, often at a point where an artery crosses over it. Several factors can increase your risk of developing RVO:
· Age (most common in people over 65)
· High blood pressure
· High cholesterol
· Diabetes
· Glaucoma
· Smoking
· Blood clotting disorders
· Cardiovascular diseases
In younger patients, conditions such as hypercoagulability (increased tendency for blood clotting) and vasculitis (inflammation of blood vessels) can be important risk factors.
Diagnosis
If you experience sudden vision changes, it’s crucial to see an eye specialist (ophthalmologist) immediately. The diagnostic process for RVO typically involves:
1. Comprehensive Eye Examination: Your doctor will dilate your pupils and examine your retina using an ophthalmoscope.
2. Optical Coherence Tomography (OCT): This non-invasive imaging test provides detailed cross-sectional images of your retina, helping to detect macular oedema (swelling) and other complications.
3. Fluorescein Angiography: A special dye is injected into your arm, which then travels to the blood vessels in your eye. Photos are taken to reveal any blocked or leaking blood vessels.
4. Visual Acuity and Visual Field Tests: These assess how well you can see at various distances and check for any blind spots in your vision.
5. Tonometry: This test measures the pressure inside your eye, as elevated pressure can be a risk factor for RVO.
Your doctor may also recommend blood tests to check for underlying conditions that could increase your risk of RVO.
Treatment Options
While there’s no cure for RVO, several treatments can help manage complications and preserve vision. The choice of treatment depends on the type and severity of your RVO, as well as any complications:
1. Anti-VEGF Injections
Anti-vascular endothelial growth factor (anti-VEGF) drugs are often the first-line treatment for RVO, especially when macular oedema is present. These medications are injected into the eye to reduce swelling and prevent the growth of abnormal blood vessels. Common anti-VEGF drugs include:
· Aflibercept
· Ranibizumab
· Bevacizumab
You may need multiple injections over a period of months or years for optimal effect.
2. Intravitreal Corticosteroid Injections
Steroid injections into the eye can help reduce inflammation and macular oedema. These may be used in combination with or as an alternative to anti-VEGF treatments.
3. Laser Therapy
Two types of laser treatments may be used:
· Focal Laser Photocoagulation: This targets specific leaking blood vessels near the macula to reduce swelling.
· Panretinal Photocoagulation (PRP): Used in more severe cases, PRP creates tiny burns on the retina to prevent the growth of abnormal blood vessels and reduce the risk of complications.
4. Vitrectomy Surgery
In cases of severe bleeding or retinal detachment, a surgical procedure called vitrectomy may be necessary to remove blood from the eye and repair any retinal damage.
New treatments for retinal vein occlusion (RVO)
There are several new treatments for retinal vein occlusion (RVO) being developed and recently approved:
1. Vabysmo (faricimab): This drug was recently approved by the FDA and European Commission for treating macular oedema due to RVO. Vabysmo has shown
sustained vision improvements and retinal drying for up to 72 weeks in clinical trials1.
2. Tarcocimab (KSI-301): This novel antibody biopolymer conjugate is being evaluated in the phase 3 BEACON trial for macular oedema secondary to RVO. It has met its primary endpoint of non-inferior visual acuity gains with fewer doses compared to standard treatments.
3. Near-infrared light therapy: A clinical trial called NIRVO is investigating the use of near-infrared light for treating macular oedema from RVO. This non-invasive approach aims to stimulate cellular metabolism and repair.
These new treatments offer potential advantages such as longer-lasting effects, reduced treatment frequency, and non-invasive options. Ongoing research continues to explore innovative approaches to improve outcomes for patients with RVO.
Living with Retinal Vein Occlusion
Living with RVO can be challenging, but there are strategies to help you maintain your quality of life:
1. Regular Monitoring: Attend all follow-up appointments with your eye specialist to monitor your condition and adjust treatment as needed.
2. Manage Underlying Conditions: Control risk factors such as high blood pressure, diabetes, and high cholesterol through medication and lifestyle changes.
3. Use Low Vision Aids: Magnifiers, large-print books, and screen reader software can help you with daily tasks if you experience vision loss.
4. Optimize Lighting: Ensure your home has good, uniform lighting to enhance visual clarity and reduce eye strain.
5. Leverage Technology: Use devices with text-to-speech functionality and consider specialized appliances like talking microwaves or scales.
6. Workplace Accommodations: Discuss your condition with your employer to arrange any necessary adjustments to your work environment or schedule.
7. Join Support Groups: Connecting with others who have similar experiences can provide emotional support and practical tips for managing RVO.
Prognosis
The outlook for RVO varies depending on the type, severity, and how quickly treatment is initiated. Many patients maintain good vision with proper management, while others may experience some degree of permanent vision loss. About 60% of patients with RVO maintain visual acuity of 20/50 or better.
Prevention
While not all cases of RVO can be prevented, you can reduce your risk by:
· Controlling high blood pressure, diabetes, and high cholesterol
· Quitting smoking
· Maintaining a healthy weight
· Exercising regularly
· Having regular eye exams, especially if you have risk factors for RVO
Conclusion
Retinal vein occlusion is a serious eye condition that requires prompt medical attention. With early diagnosis and appropriate treatment, many patients can maintain good vision and quality of life. If you experience sudden changes in your vision, seek immediate medical care. Remember, your eye health is an important part of your overall well-being, and taking proactive steps to manage RVO can make a significant difference in your long-term outcomes.