This one's a classic.  65 year old male with history of hypertension that has stopped his blood pressure medications recently in favor of diet and exercise.  He has not seen his primary care doctor for over a year. Sudden onset "spots in his right eye" was what led him to making the appointment. The above photograph reveals an obvious issue -- there's a lot of blood in the eye!

Central Retinal Vein Occlusions are often associated with underlying systemic medical conditions, chiefly hypertension and diabetes.  Any medical condition affecting blood flow can be a possible risk factor, from hypercoaguable blood disorders to hardened arteries from high cholesterol.  While it is possible to see vein occlusions in younger patients, over 90% of CRVOs occur in patients over age 55.

Retinal vein occlusions occur due to an obstruction in blood flow.  Somehow either due to a spike in blood pressure or hardening of a nearby artery wall, the flow of blood in the vein is blocked, causing a backflow of pressure and the vein to resultantly leak its contents into the nearby tissue.  In this case, the central retinal vein that delivers de-oxygenated blood out of the eye became obstructed, and blood then filled the entire retinal tissue as the vein leaked out.  You can see in this patient's photograph that the arteries are very thin; significantly narrowed compare to the veins.  This finding indicates chronic blood pressure issues (narrowed arterioles are a classic sign), but also this appearance is more exaggerated because the veins are dilated or larger than they would typically appear.  Due to the backflow of pressure following the occlusive event, the blood flow through the arteries and veins is very irregular and can lead to further ischemic (or oxygen loss) damage if the underlying systemic issues aren't improved.

Treatment for CRVO include controlling any underlying systemic conditions, and anti-VEGF injections to reduce swelling in the macula.  The CRUISE study solidified anti-VEGF treatment as a viable option for improving vision and also reducing macular edema on OCT imaging.  Vision may not return to normal despite best efforts, with worse presenting vision being associated with a worse prognosis for visual improvement.  Those eyes with more damage to the retinal tissue from oxygen loss (ischemic CRVOs) will have worse prognosis for visual outcome, and a greater risk for glaucoma and iris neovascularization after the event.  Even after resolution of CRVO, it is possible for hemorrhages to remain visible in the eye, and changes in blood vessel anatomy (collateral vessels) may occur as your eye tries to repair itself. At regular eye exams, your doctor will be looking for signs of ischemia or oxygen deprivation in the retina, as well as for any signs of increased eye pressure or possible glaucoma.

Wouldn't it be incredible if you could see your own blood vessels inside your body?  What if you could see your own brain tissue?

Wait.  You can with retinal photography.  Every day I take photos of the back (and front) of my patient's eyes and it is amazing how much information can be gleaned.  Your eye doctor can detect high blood pressure, high cholesterol, and diabetes just from looking for changes in your eyes.  Sometimes detecting these changes can save a person's vision from permanent damage; sometimes they can even save them from the repercussions of serious systemic diseases.

I can't recommend having a comprehensive eye examination more, even if you have no vision issues.  We all should want to see the inner workings of our bodies, and the eye is the perfect window inside!

Here are some of the photographs I have taken of common ocular conditions and diseases just this year.  I apologize about the persistent artifacts from my camera -- they look like 2 white circular glare areas in every photo.

MYELINATED NERVE FIBER LAYER (looks bad, but this is actually a harmless finding ) Myelination typically only exists behind the eye, but sometimes passes into the eye without harming vision

SCATTERED DRUSEN Enlarge this photo and you will see tiny yellow areas that are known as drusen near the dark central vision spot (the macula) Drusen are harmless by themselves, but can put you at a heightened risk for Macular Degeneration

CENTRAL RETINAL VEIN OCCLUSION This prompts an immediate referral and investigation for systemic health issues

CENTRAL SEROUS RETINOPATHY The area of edema is visible as subtle color changes around the macula This condition causes central vision changes, and is often due to stress Usually no treatment is necessary, just time for the swelling to resolve

ADULT VITELLIFORM DYSTROPHY See the yellow area at the macula?  It shouldn't be there.  This condition can cause central vision disruption, and no real treatment exists

Imagine not being able to see--not even when you put on glasses!  This is what people who are legally blind face every single day.  And according to the most recent report from the National Eye Institute, the rate of blindness in Americans over age 40 has increased by 23% just since 2000.  America is an aging population, and with age comes an increased prevalence for visually devastating diseases like glaucoma and macular degeneration.  All reports show that we are not doing a good enough job at preventing vision loss before it is too late.