What causes bleeding in the right eye?

Causes of Eye Bleeding

Eye bleeding has multiple distinct causes depending on the specific location and type of hemorrhage, with the most common being vitreous hemorrhage from posterior vitreous detachment with retinal tears, proliferative diabetic retinopathy, retinal vein occlusions, and less commonly, retinal artery occlusions or trauma. 1, 2

Primary Causes by Location and Mechanism

Vitreous Hemorrhage (Most Common)

Posterior Vitreous Detachment with Retinal Tears

• When the vitreous detaches from the retina, it causes traction at sites of vitreoretinal adhesion, potentially tearing retinal vessels and causing bleeding into the vitreous cavity 1, 2
• 8-22% of patients with acute posterior vitreous detachment symptoms have a retinal tear at initial examination 1, 3
• Two-thirds of patients presenting with vitreous hemorrhage have at least one retinal break, with 88% of breaks occurring in superior quadrants 1
• Direct correlation exists between the amount of vitreous hemorrhage and likelihood of retinal tear 1, 3

Proliferative Diabetic Retinopathy

• Global retinal ischemia triggers neovascularization at the inner retinal surface and into the vitreous 2
• These fragile new vessels on or near the optic disc are prone to rupture, causing vitreous hemorrhage 2
• This represents one of the most common causes in elderly patients 4

Retinal Vein Occlusions

• Branch retinal vein occlusion (BRVO) or central retinal vein occlusion (CRVO) can lead to retinal neovascularization and subsequent vitreous hemorrhage 1
• Eyes with significant capillary nonperfusion develop retinal neovascularization and vitreous hemorrhage 1
• Risk factors include arterial hypertension, hyperlipidemia, diabetes, coronary artery disease, and carotid occlusive disease 1

Retinal Artery Occlusions (Less Common, Different Presentation)

Embolic or Thrombotic Causes

• Central retinal artery occlusion (CRAO) typically presents with sudden painless vision loss, not bleeding per se, but with retinal hemorrhages visible on examination 1
• 71% of patients with CRAO have ipsilateral carotid plaque 1
• In patients over 50 years, giant cell arteritis must be suspected and requires urgent systemic corticosteroid therapy 1
• In younger patients (under 50), workup for vasculitis or hypercoagulability is indicated 1

Trauma-Related Hemorrhage

Blunt or Penetrating Trauma

• Both types can cause vitreous hemorrhage, hyphema (blood in anterior chamber), or subretinal hemorrhage 1, 2
• Trauma-induced posterior vitreous detachment occurs at younger ages than typical age-related detachment 2
• One case demonstrated traumatic total hyphema with subretinal hemorrhage requiring surgical intervention 5

Rare but Important Causes

Bleeding Disorders

• Hemophilia can present with recurrent ocular hemorrhage, including hyphema and peribulbar hemorrhage 5
• Thrombolysis with streptokinase can cause rare forms of ocular bleeding including endocapsular hematoma 6
• Family history of prolonged bleeding in X-linked pattern should raise suspicion 5

Vascular Abnormalities

• Post-traumatic pseudoaneurysm of internal carotid artery can cause recurrent bleeding 7
• Retinal phlebitis may be associated with branch retinal vein occlusion 1

Critical Clinical Distinctions

Warning Signs Requiring Emergency Evaluation

• New-onset floaters with flashes of light (photopsias) 3
• Floaters accompanied by peripheral visual field loss 3
• Sudden decrease in visual acuity 3
• Shower of new floaters or "smoke" in vision suggesting vitreous hemorrhage 3

Age-Related Patterns

• Elderly patients: Spontaneous vitreous hemorrhage usually from diabetic retinopathy, posterior vitreous detachment, or retinal vein occlusion 4
• Younger patients (under 50): Consider vasculitis, hypercoagulability, or trauma 1
• Patients over 50 with arterial occlusion: Must rule out giant cell arteritis and embolic sources 1

Common Pitfalls to Avoid

• Overlooking bleeding disorders before contemplating ophthalmic surgery, which can cause intraoperative and postoperative complications 5
• Failing to recognize that retinal breaks can develop weeks after initial posterior vitreous detachment symptoms (2-5% risk in following weeks) 1, 3
• Missing systemic associations: Patients with retinal vein occlusions have increased risk of cardiovascular events and all-cause mortality 1
• Underestimating stroke risk: Retinal artery occlusions are associated with life-threatening conditions including carotid occlusive disease and cardiac valve disease, requiring immediate stroke center referral 1