This site is designed to help fellow patients get a quick start toward understanding more about central retinal vein occlusion (CRVO).

What is a central retinal vein occlusion (CRVO)?  
The word “occlude” (as in “occlusion”) means to stop up or obstruct. A central retinal vein occlusion occurs when the vein that carries blood out of the inside part of the eye, the central retinal vein, becomes fully or partially blocked. Let's take a minute to look at what this means... 

In a normal eye, light passes through the cornea, pupil and lens on its way to the back wall of the eye. Covering the back wall of the eye is a thin layer of nerve tissue called the retina which senses this incoming light.  A cross-section of the retina is shown here in yellow.

The optic nerve is a cord like structure that extends from the back of the eye. The optic nerve carries sensory signals from the retina to the brain.

For a short distance along the center of the optic nerve there is a narrow channel containing two main blood vessels which serve the retina.

The central retinal artery (CRA) brings oxygenated blood into the eye. As the artery enters the back of the eye it branches into progressively smaller and smaller vessels until blood reaches almost all areas of the retina. (These vessels rest against the curved back wall of the eye.) 




After the blood has made its way through the capillaries and delivered its nutrients and oxygen to the retina, the blood leaves the eye through a similar system of veins, shown in blue.  The main vein leading out of the interior portion of the eye is the central retinal vein (CRV).


A CRVO occurs when the CRV becomes fully or partially blocked by what is usually assumed to be the formation of a blood clot within the CRV. The exact location of this blockage is a matter of debate.  Some authorities believe that the blockage typically forms right where the optic nerve enters the back wall of the eye, at a structure called the lamina cribrosa,2 while others believe that in milder cases the clot may form further back in the CRV, away from the central cavity of the eye3.


In summary then, a central retinal vein occlusion is a blockage of the central retinal vein which prevents oxygen depleted blood from freely flowing out of the inside portion of the eye.


Website Overview

The remainder of this website is designed to help you be better prepared for conversations with your doctor as together you consider how to best move forward in your particular circumstances.  

·         First we’ll learn a little about the tests and exams that your doctor may use to assess and classify the severity of your condition.

·         Then, we’ll look at three of the damaging aftereffects of CRVO which may, or may not, occur in your case: macular edema, retinal ischemia and neovascularization. 

·         Next, we’ll examine more closely some of the treatments which are currently available.

·         We'll consider the risk factors that may have had a role in the development of your CRVO or may have an influence on potential future eye problems.

·         And finally, we will explore information on the course of CRVO - "What happens after a CRVO?"


But First...

If you or someone you care about has been diagnosed with CRVO, one of the most important things to understand is that you are not alone.  CRVO affects an estimated 2.5 million people worldwide.1 And although you may never personally meet another individual with CRVO, there is no reason to remain isolated.

Several years ago an internet support group was formed specifically for those dealing with CRVO. This group is a caring community of fellow patients offering words of encouragement and support. Join us and become a part of the continuing conversation.

·    CRVO Support Group

You may also need some help finding an ophthalmologist who specializes in taking care of structures at the back of the eye - a retina/vitreous specialist (vitreo-retinal specialist).

·         Find an Ophthalmologist

·         Find a Retina Specialist

·         Top U.S. Ophthalmology Hospitals

And finally, if you are at a loss for what to ask your retina specialist during your first appointment, here are a few starter questions to consider. Knowing the answers to questions like these will enable you to look for information more specifically related to your particular circumstances.


Had enough of these concepts?  Click here for more notes.
Need more information on these ideas?   View a 5 minute video illustrating these concepts more thoroughly:


1. Rogers S, McIntosh RL, Cheung N, Lim L, Wang JJ, Mitchell P, Kowalski JW, Nguyen H, Wong TY; International Eye Disease Consortium. The prevalence of retinal vein occlusion: pooled data from population studies from the United States, Europe, Asia, and Australia. Ophthalmology. 2010 Feb;117(2):313-9. [PubMed] [Full Text Free]

2. Green WR, Chan CC, Hutchins GM, Terry JM. Central retinal vein occlusion: a prospective histopathologic study of 29 eyes in 28 cases. Trans Am Ophthalmol Soc. 1981;79:371-422. [PubMed] [Full Text Free]

3. Hayreh SS. Central Retinal Vein Occlusion. In: Mausolf FA, editor. The Eye and Systemic Disease, ed. 2. St. Louis: CV Mosby, 1980, p.223-275.

Acknowledgements: All images based on illustrations courtesy of National Eye Institute, National Institutes of Health.

Disclaimer: Since I am only a fellow patient and have no medical background you should not base any of your medical decisions on these notes or videos. Seek the advice of a competent medical professional promptly before making medical decisions.

Copyright © 2011, crvo_my

Special Thanks: To my wife and kids who allowed me the time to put together this site and to the Lord Jesus Christ, apart from whom I would never have thought to try and help anyone but myself. He is the One who brought you any help you may find here. Life.

Comments, complaints, corrections or suggestions regarding this website may be addressed to crvo_my "at" yahoo.com.