Understanding Retinal Vein Occlusions and Retinal Artery Occlusions
The retinal vessels in the eye are subject to the same conditions that affect other vessels in the body namely high blood pressure, high cholesterol, and hardening of the arteries (atherosclerosis). In some people with cardiovascular risk factors or existing cardiovascular disease such as heart attack or stroke, the retinal blood vessels can become either partially or completely occluded. This can cause a rapid, painless loss of vision in a sector or completely. These conditions often require the help of an Internist or Cardiologist in controlling blood pressure, cholesterol and other cardiovascular risk factors. If a retinal vascular occlusion occurs before the age of 55, further testing may be needed. The amount of vision that can be restored depends on the severity of the occlusion and usually, follow-up evaluations are necessary to check for the development of other conditions such as macular edema or neovascularization that can cause further vision loss or even cause loss of the eye.
Macular edema, or swelling of the central retina, is common after retinal vein occlusions and can cause further loss of vision. In many cases, this can be treated with anti-VEGF or steroid medication injections into the eye and/or laser to improve and preserve vision.
Another concerning side effect of retinal vascular occlusions is the growth of abnormal vessels called neovascularization. Neovascularization indicates severe retinal damage and can cause large bleeds into the eye, scar tissue formation, and severe glaucoma. It is typically treated with a retinal laser procedure called pan-retinal photocoagulation and may sometimes require intraocular medication injections.
Risk factors for retinal vascular occlusions
- High blood pressure
- High cholesterol
- Cardiovascular disease (eg: heart attack, stroke)
- Diabetes Mellitus
- Smoking or tobacco use
- Oral contraception
Symptoms of Retinal vein occlusion or retinal artery occlusion
- Rapid onset of blurred vision or loss of vision in one eye
- Worse vision in one eye when waking up
- No pain
Understanding Macular Pucker / Epiretinal Membrane (ERM)
Approximately 10% of all people over the age of 50 will develop a thin membrane commonly called a macular pucker or epiretinal membrane (ERM) over their central retina called the macula. It is not fully understood why this membrane develops but over time, ERMs can contract and distort the retina. For many people, it only causes mild blurred vision, distortion, or double vision in one eye that does not greatly affect lifestyle. If however, the symptoms become severe enough, the patient may be a candidate to have the membrane peeled off by a retina surgeon.
Risk Factors of Macular Pucker:
- Age over 55
- Macular pucker in the other eye
- Long-standing vitreous floaters
- Prior retinal tears or detachments
- Ocular inflammation (eg: iritis, uveitis)
Symptoms of Macular Pucker:
- Blurry vision
- Double vision in one eye
- Diminished color contrast
Treatment of Macular Pucker:
- Observation: Most cases do not require treatment and can just be monitored.
- Membrane peel: In this outpatient surgery, the vitreous gel is removed the membrane is then carefully peeled off the surface of the macula. The removed vitreous is then replaced with gas or saline. Vision usually recovers over the course of the next 6-24 months.