Retinal Vascular Disease

Retinal vascular diseases are conditions affecting the blood vessels that supply the retina, the light-sensitive tissue at the back of the eye. These include retinal vein occlusion, retinal artery occlusion, and related conditions. They can cause sudden or gradual vision loss and often indicate underlying cardiovascular risk factors.

Types of Retinal Vascular Disease

Retinal Vein Occlusion (RVO)

Central Retinal Vein Occlusion (CRVO):

• Blockage of main vein draining the retina
• Sudden painless vision loss
• Extensive retinal hemorrhages
• Can be mild (non-ischemic) or severe (ischemic)

Branch Retinal Vein Occlusion (BRVO):

• Blockage of a branch vein
• Often at arteriovenous crossing
• Affects part of the visual field
• Most common type of RVO

Retinal Artery Occlusion (RAO)

Central Retinal Artery Occlusion (CRAO):

• Blockage of main artery supplying retina
• Medical emergency—equivalent to an eye stroke
• Sudden, severe, painless vision loss
• Limited time window for treatment

Branch Retinal Artery Occlusion (BRAO):

• Blockage of branch artery
• Affects portion of vision
• May be less severe than CRAO

Ocular Ischemic Syndrome

• Chronic reduced blood flow to eye
• Usually from carotid artery disease
• Can cause progressive vision loss

Symptoms

Retinal Vein Occlusion

• Sudden or gradually worsening blurred vision
• Usually painless
• May notice missing areas of vision (BRVO)
• Floaters
• Vision may fluctuate

Retinal Artery Occlusion

• Sudden, severe, painless vision loss
• May be preceded by transient vision loss episodes (amaurosis fugax)
• Usually in one eye
• Vision often reduced to counting fingers or less

Risk Factors

Common to Both Vein and Artery Occlusions

• Hypertension (most important)
• Diabetes
• High cholesterol
• Smoking
• Cardiovascular disease
• Age over 50

Specific to Vein Occlusions

• Glaucoma
• Blood disorders (hypercoagulability)
• Oral contraceptives

Specific to Artery Occlusions

• Carotid artery disease
• Heart valve disease or atrial fibrillation
• Giant cell arteritis (especially in elderly)
• Systemic infections such as HIV retinopathy

How Retinal Vascular Disease Is Diagnosed

Eye Examination

• Visual acuity testing
• Pupil examination (afferent defect in CRAO)
• Dilated fundus examination
  • Retinal hemorrhages (RVO)
  • Pale retina with cherry-red spot (CRAO)
  • Emboli visible in some cases

Imaging

Optical Coherence Tomography (OCT):

• Detects macular edema
• Monitors treatment response

Fluorescein Angiography:

• Shows blood flow patterns
• Identifies areas of poor circulation
• Guides treatment

OCT Angiography:

• Non-invasive blood flow imaging

Systemic Evaluation

After diagnosis, evaluation for systemic risk factors:

• Blood pressure measurement
• Blood glucose and HbA1c
• Cholesterol panel
• Carotid ultrasound (especially for artery occlusion)
• Cardiac evaluation if indicated
• ESR and CRP if giant cell arteritis suspected
• Infectious disease workup when indicated (e.g., malaria retinopathy)

Treatment

Retinal Vein Occlusion

For macular edema (main cause of vision loss):

Anti-VEGF injections:

• Aflibercept (Eylea), ranibizumab (Lucentis), bevacizumab (Avastin)
• Reduces swelling, improves vision
• Given monthly initially, then as needed
• Most effective treatment

Steroid injections:

• Dexamethasone implant (Ozurdex)
• Triamcinolone
• For patients not responding to anti-VEGF

Laser treatment:

• For abnormal new blood vessel growth
• Less commonly used now for macular edema

Retinal Artery Occlusion

CRAO—Emergency priorities:

• Treat as an ocular stroke and seek immediate emergency evaluation
• Urgent ophthalmology and stroke-team assessment
• Thrombolytics may be considered only in select cases at experienced centers within strict time windows
• No conservative bedside maneuver has shown consistent visual benefit

Critical: Systemic workup:

• Stroke prevention is paramount
• Carotid imaging
• Cardiac evaluation
• Giant cell arteritis workup if over 50
• Blood thinners if indicated

Managing Underlying Conditions

• Blood pressure control
• Diabetes management
• Cholesterol treatment
• Smoking cessation
• Treatment of carotid disease if present

Prognosis

Retinal Vein Occlusion

• Variable depending on severity
• Non-ischemic CRVO: ~50% regain good vision
• Ischemic CRVO: poor visual prognosis
• BRVO: generally better outcomes than CRVO
• Macular edema is main cause of vision loss—treatable

Retinal Artery Occlusion

• Generally poor visual outcomes for CRAO
• Only 10-15% recover significant vision
• BRAO has better prognosis
• Systemic stroke risk is significant—prevention is crucial

Complications

• Macular edema (swelling affecting central vision)
• Neovascularization (abnormal new blood vessel growth)
• Neovascular glaucoma (in ischemic CRVO)
• Vitreous hemorrhage
• Stroke or heart attack (related systemic disease)

Prevention

• Control blood pressure
• Manage diabetes
• Treat high cholesterol
• Don't smoke
• Regular eye exams
• Regular medical checkups

Frequently Asked Questions

Is retinal vein occlusion the same as a stroke?

It's sometimes called an "eye stroke" because it involves blood vessel blockage. While not identical to brain stroke, it indicates similar risk factors and increases stroke risk. Systemic evaluation is important.

Will my vision come back?

For vein occlusions, treatment of macular edema can often improve or stabilize vision. For artery occlusions, especially CRAO, significant vision recovery is unfortunately uncommon.

Can this happen to my other eye?

Risk exists for the other eye, particularly with uncontrolled risk factors. Controlling blood pressure, diabetes, and other factors reduces this risk.

Why do I need heart and blood vessel tests?

Retinal vascular occlusions often indicate systemic vascular disease. The same process affecting your eye may affect your heart or brain. Evaluation helps prevent stroke and heart attack.

How often do I need injections?

For vein occlusions with macular edema, injections typically start monthly, then frequency is adjusted based on response. Some people need ongoing treatment; others can stop after swelling resolves.

What if I had brief vision loss that came back?

Transient vision loss (amaurosis fugax) is a warning sign of possible impending artery occlusion or stroke. This requires urgent evaluation, not reassurance that "it came back."

References