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Central Retinal Vein Occlusion and Branch Retinal Vein Occlusion

(Retinal Vein Occlusion)


Sonia Mehta

, MD, Vitreoretinal Diseases and Surgery Service, Wills Eye Hospital, Sidney Kimmel Medical College at Thomas Jefferson University

Reviewed/Revised Apr 2022 | Modified Sep 2022
Topic Resources

Central retinal vein occlusion is a blockage of the central retinal vein by a thrombus. It causes painless vision loss, ranging from mild to severe, and usually occurs suddenly. Diagnosis is by funduscopy. Treatments can include antivascular endothelial growth factor drugs (eg, ranibizumab, pegaptanib, bevacizumab), intraocular injection of a dexamethasone implant or triamcinolone, and laser photocoagulation.


Major risk factors include

Other risk factors include

Occlusion may also be idiopathic. The condition is uncommon among young people. Occlusion may affect a branch of the retinal vein or the central retinal vein.

Neovascularization (abnormal new vessel formation) of the retina or iris (rubeosis iridis) occurs in about 16% of patients with central retinal vein occlusion and can result in secondary (neovascular) glaucoma, which can occur weeks to months after occlusion. Vitreous hemorrhage may result from retinal neovascularization.

Symptoms and Signs

Painless vision loss is usually sudden but it can also occur gradually over a period of days to weeks. Funduscopy reveals hemorrhages throughout the retina, engorged (dilated) and tortuous retinal veins, and, usually, significant retinal edema. These changes are typically diffuse if obstruction involves the central retinal vein and are limited to one quadrant if obstruction involves only a branch of the central retinal vein.


  • Funduscopy

  • Color fundus photography

  • Fluorescein angiography

  • Optical coherence tomography

The diagnosis is suspected in patients with painless vision loss, particularly those with risk factors. Funduscopy, color photography, and fluorescein angiography confirm the diagnosis. Optical coherence tomography is used to determine the degree of macular edema and its response to treatment. Patients with a central retinal vein occlusion are evaluated for hypertension Hypertension Hypertension is sustained elevation of resting systolic blood pressure (≥ 130 mm Hg), diastolic blood pressure (≥ 80 mm Hg), or both. Hypertension with no known cause (primary; formerly, essential... read more Hypertension and glaucoma Overview of Glaucoma Glaucomas are a group of eye disorders characterized by progressive optic nerve damage in which an important part is a relative increase in intraocular pressure (IOP) that can lead to irreversible... read more and tested for diabetes Diabetes Mellitus (DM) Diabetes mellitus is impaired insulin secretion and variable degrees of peripheral insulin resistance leading to hyperglycemia. Early symptoms are related to hyperglycemia and include polydipsia... read more . Young patients are tested for increased blood viscosity (with a complete blood count and clotting factors as deemed necessary).


Most patients have some visual deficit. In mild cases, there can be spontaneous improvement to near-normal vision over a variable period of time. Visual acuity at presentation is a good indicator of final vision. If visual acuity is at least 20/40, visual acuity will likely remain good, occasionally near normal. If visual acuity is worse than 20/200, it will remain at that level or worsen in 80% of patients. Central retinal vein occlusions rarely recur.


  • For macular edema, intraocular injection of antivascular endothelial growth factor (anti-VEGF) drugs, dexamethasone implant, and/or triamcinolone acetonide

  • For some cases of macular edema with branch retinal vein occlusion, focal laser photocoagulation

  • Panretinal laser photocoagulation if neovascularization develops

Treatment for branch retinal vein occlusion in patients with macular edema that involves the fovea is usually intraocular injection of an anti-VEGF drug (eg, ranibizumab, aflibercept, or bevacizumab) or intraocular injection of triamcinolone or a slow-release dexamethasone implant. These treatments can also be used to treat central retinal vein occlusion in patients with macular edema. With these treatments, vision improves significantly in 30 to 40% of patients.

Focal laser photocoagulation can be used for branch retinal vein occlusion with macular edema but is less effective than intraocular injection of an anti-VEGF drug or a dexamethasone implant. Focal laser photocoagulation is typically not effective for the treatment of macular edema due to a central retinal vein occlusion.

If retinal or anterior segment neovascularization develops secondary to central or branch retinal vein occlusion, panretinal laser photocoagulation should be done promptly to decrease vitreous hemorrhage and prevent neovascular glaucoma.

Key Points

  • Retinal vein occlusion involves blockage by a thrombus.

  • Patients have painless loss of vision that is typically sudden and may have risk factors (eg, older age, hypertension).

  • Funduscopy characteristically demonstrates macular edema with dilated veins and hemorrhages; additional tests include color fundus photography, fluorescein angiography, and optical coherence tomography.

  • Treat patients who have macular edema with an intraocular injection of an anti-VEGF drug (ranibizumab, aflibercept, or bevacizumab) or intraocular injection of a dexamethasone implant or triamcinolone.

  • Focal laser photocoagulation is useful in some cases of macular edema secondary to a branch retinal vein occlusion, and panretinal laser photocoagulation should be done for retinal or anterior segment neovascularization.

Drugs Mentioned In This Article

Drug Name Select Trade
Byooviz, CIMERLI, Lucentis, Susvimo
Alymsys, Avastin, MVASI, Zirabev
AK-Dex, Baycadron, Dalalone, Dalalone D.P, Dalalone L.A, Decadron, Decadron-LA, Dexabliss, Dexacort PH Turbinaire, Dexacort Respihaler, DexPak Jr TaperPak, DexPak TaperPak, Dextenza, DEXYCU, DoubleDex, Dxevo, Hemady, HiDex, Maxidex, Ocu-Dex , Ozurdex, ReadySharp Dexamethasone, Simplist Dexamethasone, Solurex, TaperDex, ZCORT, Zema-Pak, ZoDex, ZonaCort 11 Day, ZonaCort 7 Day
Aristocort, Aristocort A, Aristocort Forte, Aristocort HP, Aristo-Pak, Aristospan, Azmacort, Children's Nasacort Allergy 24HR Nasal Spray, Cinalog, Cinolar, Flutex, Hexatrione, Kenalog, Kenalog in Orabase, Kenalog-10, Kenalog-40, Kenalog-80, Nasacort, Nasacort AQ, Oralone, SP Rx 228 , Tac-3 , Triacet , Triamonide , Trianex , Triderm , Triesence, XIPERE, Zilretta
AK-Fluor, Bio Glo, Fluorescite, Fluorets , Fluor-I-Strip, Fluor-I-Strip A.T., Ful-Glo, Ophthalmicflur
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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