Central Retinal Vein Occlusion - Patients - The American Society of Retina Specialists
`
`Facts from the Foundation of the ASRS
`RETINA HEALTH SERIES
`Committed to improving the quality of life of
`all people with retinal disease
`
`Central Retinal Vein Occlusion
`Central retinal vein occlusion, also known as CRVO, is a condition in
`which the main vein that drains blood from the retina closes off
`partially or completely. This can cause blurred vision and other
`problems with the eye.
`
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`Symptoms
`Mild CRVO may show no symptoms. However:
`
`Many patients with CRVO have symptoms such as blurry or distorted
`vision due to swelling of the center part of the retina, known as the
`macula.
`Some patients have mild symptoms that wax and wane, called
`transient visual obscurations.
`Patients with severe CRVO and secondary complications such as
`glaucoma (a disease characterized by increased pressure in the eye)
`often have pain, redness, irritation and other problems.
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`Central Retinal Vein Occlusion - Patients - The American Society of Retina Specialists
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`Causes
`Most patients with CRVO develop it in one eye. And, although diabetes and high blood pressure are risk factors for
`CRVO, its specific cause is still unknown. What we do know is that CRVO develops from a blood clot or reduced blood
`flow in the central retinal vein that drains the retina. And we have learned that a large number of conditions may
`increase the risk of blood clots. Some eye doctors advise testing for them. However, it is not certain how these health
`conditions are related to CRVO—and some of them, if diagnosed, have no agreed-to or necessary recommended
`treatment.
`
`Many eye doctors do not advise testing for a CRVO in one eye, but do recommend a visit with a family doctor to be
`sure there is no diabetes or high blood pressure.
`
`CRVO that occurs in both eyes at the same time can be related to systemic disease; in these cases, a tendency
`toward abnormal blood clotting is definitely more common and medical testing to detect so-called “hypercoagulable
`states” is indicated. While some eye doctors coordinate such testing, most refer patients to their family doctors,
`internists, or hematologists (physicians specializing in diseases of the blood) for testing.
`
`Diagnostic testing
`CRVO is typically a clinical diagnosis—that is, one based on medical signs and patientreported symptoms. When a
`retina specialist looks into the eye, there is a characteristic pattern of retinal hemorrhages (bleeding) and a diagnosis is
`made (Figure 1).
`
`Common conditions that can take on an appearance of CRVO include diabetic retinopathy (retina disease) and
`retinopathy related to low blood counts, such as anemia and thrombocytopenia (a deficiency of blood platelets).
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`Central Retinal Vein Occlusion - Patients - The American Society of Retina Specialists
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`Figure 2. OCT of an acute CRVOwith severe macular
`
`edema. Image courtesy of John Thompson, MD
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`Figure 1. CRVO with Flame HemorrhagesJeffrey G.
`Gross, MD. Retina Image Bank 2012; Image 968.
`©American Society of Retina Specialists.
`
`Swelling of the center of the retina, called macular edema is common,and to detect this and measure the amountof
`swelling, an optical coherence tomography (OCT)imageis often obtained (Figure 2). To help distinguish CRVO from
`conditions that may mimicit, and to assess closure of small blood vessels, or to search for or confirm growth of new
`abnormal vessels, fluorescein angiography (FA) imaging may be performed.
`
`Treatment and prognosis
`
`CRVOhasa better prognosis in young people.In older patients who receive no treatment, about one-third improve on
`their own, about one-third wax and wane and stay about the same, and about one-third get worse.If there is macular
`edema,it may improve on its own.
`
`In patients with CRVO,vascular endothelial growth factor (VEGF) is elevated; this leads to swelling as well as new
`vessels that are prone to bleeding. The most commontreatment, based on results from powerful randomizedclinical
`trials, involves periodic injections into the eye of an anti-VEGF drug to reduce the new blood vessel growth and
`swelling. Anti-VEGF drugs include bevacizumab (Avastin®), ranibizumab (Lucentis®), and aflibercept (Eylea®).
`
`Although anti-VEGF drugs reduce the swelling, they are not a cure. As the drug leaves the eye and movesinto the
`bloodstream, the effect in the eye wears off, so re-injection is often needed. A rare lucky patient needs only one
`injection, but the norm is a series of periodic injections over the course of a few years.
`
`Another option for treating macular edema from CRVOis with an injection of intraocular steroid. This could be either a
`liquid steroid called triamcinolone or a small steroid pellet called dexamathasone implant (Ozurdex(R)). The steroid
`injections typically last several months, but can cause elevated intraocular pressure requiring eye drops or increased
`rate of cataract formation.
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`Ischemic (pronounced is KEY mick) and Non-ischemic CRVO: CRVO comesin 2 types:
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`e Non-ischemic CRVO—a milder type characterized by leaky retinal vessels with macular edema
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`e
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`Ischemic CRVO—a more severetype with closed-off small retinal blood vessels
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`Central Retinal Vein Occlusion - Patients - The American Society of Retina Specialists
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`Patients with ischemic CRVO have worse vision with less chance for improvement. They have a tendency for the eye
`to cause new blood vessels to grow—and in the front of the eye, these new vessels can clog the outflow of normal eye
`fluids. The eye pressure goes up and glaucoma develops. In the back of the eye, new blood vessels may cause
`bleeding.
`
`When there is ischemic CRVO with new vessels, anti-VEGF injections lead to prompt, but often temporary, control of
`the new vessels. Laser treatment tends to offer a more permanent effect. In some cases, both treatments are used.
`
`Non-ischemic CRVO can worsen and become ischemic, so when CRVO is diagnosed, monthly checkups are initially
`recommended.
`
`It’s important to note that early detection of macular edema or abnormal blood vessels is important; most patients can
`avoid severe vision loss if treatment is begun before substantial damage develops in the eye.
`
`Authors
`THANK YOU TO THE RETINA HEALTH SERIES AUTHORS
`Sophie J. Bakri, MD
`Audina Berrocal, MD
`Antonio Capone, Jr., MD
`Netan Choudhry, MD, FRCS-C
`Thomas Ciulla, MD, MBA
`Pravin U. Dugel, MD
`Geoffrey G. Emerson, MD, PhD
`K. Bailey Freund, MD
`Roger A. Goldberg, MD, MBA
`Darin R. Goldman, MD
`Dilraj Grewal, MD
`Larry Halperin, MD
`Vi S. Hau, MD, PhD
`Suber S. Huang, MD, MBA
`G. Baker Hubbard, MD
`Mark S. Humayun, MD, PhD
`Talia R. Kaden, MD
`Peter K. Kaiser, MD
`M. Ali Khan, MD
`
`Anat Loewenstein, MD
`Mathew J. MacCumber, MD, PhD
`Maya Maloney, MD
`Timothy G. Murray, MD, MBA
`Hossein Nazari, MD
`Oded Ohana, MD, MBA
`Jonathan L. Prenner, MD
`Gilad Rabina, MD
`Carl D. Regillo, MD, FACS
`Naryan Sabherwal, MD
`Sherveen Salek, MD
`Andrew P. Schachat, MD
`Adrienne W. Scott, MD
`
`Michael Seider, MD
`Janet S. Sunness, MD
`Eduardo Uchiyama, MD
`Allen Z. Verne, MD
`Christina Y. Weng, MD, MBA
`Yoshihiro Yonekawa, MD
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`Central Retinal Vein Occlusion - Patients - The American Society of Retina Specialists
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`EDITOR
`John T. Thompson, MD
`
`SPANISH SERIES EDITORS
`J. Fernando Arevalo, MD, PhD
`Gabriela Lopezcarasa Hernandez, MD
`
`MEDICAL ILLUSTRATOR
`Tim Hengst
`
`Andres Lisker, MD
`Virgilio Morales-Canton, MD
`
`Copyright ©2016 The Foundation of the American Society of Retina Specialists. All rights reserved.
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`This resource is made possible in part through generous support from the Foundation
`of the American Society of Retina Specialists, Allergan, Genentech, Novartis, and
`Regeneron Pharmaceuticals.
`AMERICAN SOCIETY OF RETINA SPECIALISTS
`20 North Wacker Drive, Suite 2030, Chicago, Illinois 60606
`(312) 578-8760 phone
`
`
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`https://www.asrs.org/patients/retinal-diseases/22/central-retinal-vein-occlusion[12/30/2021 3:45:56 PM]
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`Central Retinal Vein Occlusion - Patients - The American Society of Retina Specialists
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`© 2021 The American Society of Retina Specialists. All rights reserved.
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`https://www.asrs.org/patients/retinal-diseases/22/central-retinal-vein-occlusion[12/30/2021 3:45:56 PM]
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