Myopic Degeneration

Did you ever wonder while growing up what your friends with the thick glasses meant when they said they were “nearsighted”?  What exactly does it mean to be nearsighted, and what issues related to vision arise from this?

Think of your eye as a camera, which has a segment to focus the light coming into it. In the eye, this focusing segment is made up of the cornea, the clear front part of the eye, the pupil, and the natural lens inside the eye behind the pupil. Like any camera, the eye has a film to make the images, and this is the retina. The retina is a thin tissue lining the entire inside of the eye like wallpaper.

Myopic Degeneration
Figure 1. Normal retina inside the eye, the optic nerve and the blood vessels

Another term for nearsightedness is myopia. When someone is myopic, they see well up close but cannot see far away. A myopic eye is longer than average in length from the front of the eye to the back of the eye. In a sense, light and images from far away cannot reach the back of the eye where the camera film, the retina, resides. Therefore, glasses or contact lens are needed to help focus the light on to the retina to see clearly. Some people may elect to have refractive surgery to correct near sightedness. Because the eye is longer than average, the tissues inside it, like the retina, can become abnormally thinned due to stretching. It should be noted that people with myopia have an increased risk for retinal tear or detachment of the retina which can lead to rapid loss of vision. If sudden flashing lights, new floaters, or darkening of peripheral vision are seen, an eye care professional should be expeditiously consulted for an evaluation.

Myopic Degeneration
Figure 2. Myopic degeneration

Progressive thinning of the retina resulting from elongation of the eyeball is termed myopic degeneration. Individuals with more severe nearsightedness or high myopia are at greater risk for developing myopic degeneration. When thinning and atrophy occur at the part of the retina that affects central vision (macula), vision may deteriorate gradually and may not be correctable.  You can see in the Figure 2 that there are some white and black discolorations that were not present in Figure 1. These changes exemplify myopic degeneration. Glasses or contact lenses cannot correct for myopic degeneration because there is actual damage of the retina tissue when it is stretched out. There is no reversal for the actual thinning of the retina and the damage to the retina.

Myopic degeneration
Figure 3. Myopic degeneration with choroidal neovascularization

When the retina is stretched out and the eye is elongated, sometimes abnormal blood vessels can develop just below the retina. These blood vessels, termed choroidal neovascularization, can interfere with focusing of the light or bleed and can cause sudden decreased vision. The reddish discoloration in Figure 3 exemplifies bleeding from choroidal neovascularization in myopic degeneration. Fortunately there is a treatment in the form of medications that can be injected into the eye that can stop the growth of these abnormal bleeding vessels, if they are found early before permanent damage occurs to the eye.  Therefore, early diagnosis as well as treatment of choroidal neovascularization can be helpful in limiting the degree of vision loss from these bleeding blood vessels.

Not everyone with myopia develops myopic degeneration, and there is currently no algorithm to predict its development. Self-testing one eye at a time using an Amsler grid, which looks like a graph paper, to check for any distortion of straight lines on a regular basis can be a useful tool to identify any early changes. Those with myopic degeneration should have a regular dilated eye examination with an eye care professional for early detection of any treatable changes.

Image References
1.Normal Retina. Jason Calhoun MD. ASRS Image Bank.
2.Myopic degeneration. Gerrardo Garcia Aguirre MD. ASRS Image Bank.
3.Myopic degeneration and CNVM. David Callanan MD. ASRS Image Bank.

4/6/16

Judy Kim - Myopic Degeneration

Judy E. Kim, MD
Medical College of Wisconsin
NEHEP Planning Committee Member

 
 
 
 
 
Alessa Crossan - Myopic Degeneration

Alessa Crossan, MD
Medical College of Wisconsin

Women’s Eye Health

With this being Women’s History Month, we thought it appropriate to discuss women’s eye heath. Your vision is one of the most important things in your life. Vision loss can make everyday tasks more difficult, impede your work and lead to depression.
women's eye health
According to Prevent Blindness America (PBA), 66% of people who are blind or visually impaired are women. This is primarily due to the fact that women have more risk factors for vision loss than men. Sadly the same study also revealed that only 9% of women realize this. Early intervention can help prevent blindness in many cases. Many blinding eye diseases can be treated to prevent blindness and almost all eye injuries can be prevented.

Here is a closer look at why women are affected more than men, and what condition they need to be aware of for early diagnosis and sight-saving treatments.

Why Women Lose Vision

  • They live longer than men and many eye diseases are age-related. Examples are cataracts, macular degeneration and diabetic retinopathy. The rates of these diseases are increasing as the baby boomer population ages.
  •  

  • Some eye diseases are intrinsically more prevalent among women, like dry eye syndrome which is believed to be linked to hormones. It is 2-3 times more likely in women than men. Hormonal changes can influence vision changes across the life span of a woman, from pregnancy to post-menopause.
  •  

  • Women have higher rates of autoimmune diseases such as lupus, rheumatoid arthritis and multiple sclerosis. The serious side effects of these conditions can affect your eyes, causing vision loss.
  •  

  • Social and economic factors can access to health care for women restricting early detection and treatment which could prevent or limit vision loss.
  •  

  • While behavioral and environmental factors are not restricted to women, poor nutrition and obesity can cause diabetes and subsequent diabetic retinopathy; while smoking is also a proven risk factor for eye diseases such as cataracts and macular degeneration. Women under 23 are the fastest growing segment of new smokers.

women's eye health
Eye Conditions More Prevalent in Women

  • Cataracts are the world’s leading cause of blindness. They are the result of a clouding of your eye’s normally clear lens. They can be treated with cataract surgery, where the cloudy lens is replaced with a clear synthetic lens.
  •  

  • Glaucoma is the second-leading cause of blindness in the Us. It is called the silent thief of sight because there is no warning. It happens when pressure in the eye — intraocular pressure or IOP — is too high, damaging the optic nerve which sends vision signals to the brain. Open-angle glaucoma, the most common type, affects men and women equally. But women are 2-4 times more likely than men to get closed-angle glaucoma. One of the possible reasons for this is that the front chamber between the iris and cornea is shallower in women than men and can block fluids from draining out of the eye, thus increasing pressure. Glaucoma is also genetic, meaning you are at higher risk if someone in your family has had glaucoma. When caught early, there are treatments that can help control your IOP. If it is not controlled early, blindness can result and it is irreversible.
  •  

  • Age-related macular degeneration (AMD) is the number one cause of vision loss in people over 40 in the US. One of the reasons women are at higher risk is because they tend to live 5-7 years longer than men. AMD gradually destroys the central part of your sight that helps you read or drive. There are two types of AMD. Dry AMD, which occurs when drusen accumulate under the retina. There is no treatment for dry, yet accounts for 90% of the cases. Wet AMD occurs when new blood vessels grow and leak between the retina and eye’s outer layer. There is a treatment of anti-VEGF injections for this version of AMD. The earlier the disease is diagnosed and treated, the better the results. Like glaucoma, it is an inherited eye disease.
  •  

  • Diabetic retinopathy is a result of diabetes. When blood sugar levels are too high, the vessels that feed the retina weaken and eventually leak, which cause the macula to swell. In its most dangerous form the retina may detach from the back of the eye leading to blindness. Diabetes is also hereditary, but controllable with early diagnosis and treatment.
  •  

  • Dry eye syndrome occurs when your eyes produce too few tears. Your eyes may burn, sting or feel gritty, making your vision blurry or you may blink more. Contrary to the name, you may appear weepy as the dryness may stimulates more tear production. Thanks to hormones, women are more susceptible. In postmenopausal women, the shift in balance between estrogen and progesterone can be responsible.
  •  

  • Pregnancy-related eye changes, like menopause, are caused by hormone shifts and can cause several temporary eye conditions, such as dry eye and corneal swelling.

3/10/16

Susan DeRemerSusan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation

4 Super Greens for Better Sight

A healthy diet not only helps your heart, but also your eyes. Your diet should include lots of fruits and vegetables to provide you with a natural source of nutrients to help protect your sight. As wonderful as supplements are, eating the actual foods is always better. Some of the best vegetables for you are the dark, leafy greens that are rich in valuable vitamins and nutrients. These are the super greens for better sight.

With the US experiencing bitter, freezing temperatures on the East Coast, while the West Coast is having summer in February, with record-breaking hot temperatures, I thought it would be interesting to see how you could enjoy those super greens, no matter what the temperature is outside. Below is a quick look at four dark leafy greens that are a great addition to a healthy diet, watercress, arugula, spinach and kale. For each vegetable I have included a recipe that is served hot, along with one that is served cold.

Here is what you need to know about super greens for better sight.
super greens
WATERCRESS

Watercress is a cruciferous plant and part of the brassica family, like arugula and kale. It contains vitamins A, B6, B12, C, K, iron, magnesium, calcium, phosphorus, lutein and zeaxanthin. In fact, weight for weight, watercress contains more vitamin C than an orange, more calcium than milk, more iron than spinach and more folate than bananas. Watercress has the highest amount of nutrients for the smallest amount of calories.

The health benefits of watercress include boosting immunity, cancer & diabetes prevention, reducing cognitive decline, thyroid support, better cardiovascular health and stronger bones. As for your eyesight, it can help prevent or slow the onset of age-related macular degeneration and possibly cataracts.

Watercress is most commonly enjoyed fresh in salads, but can also be use in pastas, casseroles, soups and sauces. Choose watercress with deep green, crisp leaves, with no signs of wilting. Trim the stems, rinse the greens in cold water and dry. It is best if used immediately, but can be store for up to four days in the refrigerator.

Watercress Soup by William Anatooskin

Watercress and Grapefruit Salad by Martha Stewart
super greens
ARUGULA

Arugula is also known as a salad or garden rocket. It is a small low growing herb that is packed with vitamins, minerals and antioxidants. It is rich in folates, vitamin A, B-complex, C and K and has copper, iron, calcium, potassium, manganese and phosphorus.

The health benefits of arugula include a lowered risk of cancer, healthy bones, strengthened brain function, improved mineral absorption and it boosts the immune system. Because of being a source of carotenoids, it also helps to slow the progression of age-related macular degeneration.

Arugula is popular in salads, used with milder greens to add a peppery flavor. But it can also be used in pastas, casseroles, pizzas, soups and sauces. Choose arugula that is crisp with green young leaves. Avoid the flowered harvest as those leaves are tough and have a bitter taste. Wash leaves in a bowl of water, swishing thoroughly to get rid of all sand and soil. Drain and pat dry before storing in the vegetable bin of your refrigerator for no more than a few days.

Grilled Stuffed Swordfish by Stormy Scarlett

Pasta Salad with Goat Cheese and Arugula by Martha Stewart
super greens
SPINACH

Spinach is a very popular leafy green vegetable, with two common varieties cultivated for food; the savory-type with dark green crinkled leaves and the flat-leaf type with smooth surfaced leaves. Spinach contains vitamin A, B-complex, C and K, along with lutein, zeaxanthin beta-carotene, potassium manganese, magnesium, copper and zinc.

The nutrients in spinach help improve blood glucose control in diabetes, lower the risk of certain cancers, reduce blood pressure, increase bone health and help iron deficiency. The lutein, zeaxanthin and beta-carotene help to potentially prevent and slow the progression of age-related macular degeneration. Lutein also works to protect the eye from free radical damage by helping filter out damaging blue and ultraviolet light.

Spinach is a universally popular vegetable, used around the world in a variety of ways, including salads, soups, noodles, pies, casseroles, dips, sauces, etc. Look for leaves that are dark green in color, crisp and not dull or yellow and spotted. Wash thoroughly to remove sand and soil, dry, trim away tough stems and store in the refrigerator for up to a week.

Turkey-Spinach Meatballs from Bon Appètit

Spinach Salad with Dates from Bon Appètit
super greens
KALE

Kale is a member of the mustard and cabbage families and has more nutrients than spinach. Less than ½ cup has 333% of the recommended daily allowance (RDA) of vitamin A, 587% RDA of vitamin K and 200% RDA of vitamin C. This frilly-leafed vegetable also has vitamin B-complex, lutein, zeaxanthin, beta-carotene, copper, calcium, sodium, potassium, iron, manganese, and phosphorus.

The health benefits of kale include healthy muscles and skin, improved blood glucose control, lower colon and prostate cancer risk, better cardiovascular health, stronger bone health, reduced neuronal brain damage and support for red blood cell formation. The advantage for your eyes comes from the lutein, zeaxanthin, beta-carotene and vitamin A, all which work to support a healthy retina. They help protect against blue and ultraviolet light as well as the early onset and progression of age-related macular degeneration. Because of the positive impact on diabetes it also reduces the onset and progression of diabetic retinopathy.

Kale is very versatile and can be served in a variety of ways including salads, soups and casseroles. It can also be braised, broiled, sautéed and even made into kale chips by tossing them in extra-virgin olive oil and sprinkled with your choice of cumin, curry powder, chili powder, red pepper flakes or garlic powder and baking at 275 degrees for 15-30 minutes depending on how crisp you want them to be. When shopping for kale look for leaves that are crispy and crunchy with a brilliant dark blue-green color. Wash thoroughly to remove soil and sand, dry well, and remove all tough stems. It is extremely perishable, so use it as quickly as possible.

Kale and Chicken Casserole by Martha Stewart

Kale with Pomegranate Dressing and Ricotta Salata from Bon Appètit

All of these dark green leafy vegetables are not only healthy for you, but can be used in many ways to make it easy to incorporate them into your diet. Here are a few ideas:

  • Throw a small handful into your blender when making your favorite smoothie
  • Add them to your next omelet or egg scramble
  • Use them for making pesto or adding to pasta sauce
  • Sauté with a small amount of extra-virgin olive and season with freshly ground black pepper and freshly grated Parmesan cheese to serve at a topping for your baked potato
  • Add it to your wrap, sandwich or flatbread

2/17/16

Susan DeRemerSusan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation

Layers of the Retina

The retina at the back of the eye is essential for all vision. Each layer of cells in this tissue serves a specific purpose. As we prepare for Age-Related Macular Degeneration Awareness Month in February, a closer look at the layers of the retina and their function.

layers of the retina

Layers of the Retina

Choroid – This is made up of a layer of blood vessels that supply oxygen and nutrients to the retina. Defect in the CHM gene can cause choroideremia, leaky blood vessels can expand in the retina causing wet age-related macular degeneration (AMD) and diabetic retinopathy.

Retinal pigment epithelium – This is a single layer of cells that provide essential nutrition and waste removal for the photoreceptor cells. Accumulation of waste can lead to AMD and Stargardt disease.

Photorecptors – This is where the rods and cones are located that convert light into electrical signals. Rods help you with night and peripheral vision. Cones are more concentrated in the macula (the central part of the retina) and proved central and color vision. Death of the rods can cause vision loss called retinitis pigmentosa, while AMD is the loss of central vision.

Horizontal cells – These cells are connect to the photoreceptors that surround the bipolar connected photoreceptor cells and help the help integrate and regulate the input from multiple photoreceptor cells, increasing your visual acuity.

Bipolar cells – The dependence of each layer of the retina on each other is exemplified here. These cells take the electrical information from the photoreceptor cells and pass it along to other retinal cells.

Ganglion cells – These cells extend to form an optic nerve that conveys information to the brain and take the electrical information from the bipolar cells and process it to determine shapes, contrast and color. Glaucoma vision loss results from high intraocular pressure that affects the optic nerve, interrupting the signals to the brain.

1/26/16


 

Susan DeRemerSusan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation

Top 10 Articles of 2015

eye facts and eye disease
In looking at the many articles we shared with you in 2015, we found that your interests were varied. From the science of vision, eye facts and eye disease to helpful suggestions to help your vision.

Here is the list of the top 10 articles you read last year. Do you have a favorite that is not on the list? Share it in the comments section below.

    1. Rods and Cones Give Us Color, Detail and Night Vision
    2. 20 Facts About the Amazing Eye
    3. Understanding and Treating Corneal Scratches and Abrasions
    4. 32 Facts About Animal Eyes
    5. 20 Facts About Eye Color and Blinking
    6. When You See Things That Aren’t There
    7. Posterior Vitreous Detachment
    8. Can Keratoconus Progression Be Predicted?
    9. Winter Weather and Your Eyes
    10. Coffee and Glaucoma: “1-2 cups of coffee is probably fine, but…”

Do you have any topics you would like to see discussed in the blog? Please leave any suggestions you might have in the comments below.

1/7/16


Susan DeRemerSusan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation

Mitochondria and Age-Related Macular Degeneration

Research on mitochondrial DNA shows promise for treating AMD

For the past few years, DEF Research Director Dr. M. Cristina Kenney has been researching the relationship of mitochondria and age-related macular degeneration (AMD). She found that damaged mitochondria from people with AMD send signals that can cause retinal cells to die at an increased rate, compared with people who had healthy mitochondria and no AMD. That research led to the exploration of stimulating mitochondria to support retinal cell health in an effort to retain or restore vision for people with AMD.

Mitochondria in Cells
Cells are the basic building blocks of all living things. The human body is composed of trillions of cells. They provide structure for the body, take in nutrients from food, convert those nutrients into energy and carry out specialized functions. Cells also contain the body’s hereditary material (DNA) and so they can make copies of themselves.

Mitochondria are tiny structures inside cells whose function is to produce energy, like a battery in a flashlight, to keep cells alive. Each cell contains hundreds to thousands of mitochondria, which are located in the fluid that surrounds the nucleus. Although most DNA is packaged in chromosomes within the nucleus of a cell (nuclear DNA), mitochondria also have a small amount of their own DNA, known as mitochondrial DNA or mtDNA.

Because only egg cells contribute mitochondria to a developing embryo, only females can pass on the mitochondrial DNA to their children.

Mitochondrial Haplogroups
The mtDNA can be classified into categories called haplogroups, which represent different ancient, geographically separated groups of people. For example, African-Americans and people of ancient African lineage have inherited L haplogroup mitochondria from their mothers no matter where they currently live.
mitochondria and age-related macular degeneration
Similarly, most Ashkenazi Jewish populations (primarily those Jews whose families originated in Eastern or Central Europe) possess mitochondria of the K haplogroup. People with this haplogroup of mtDNA seem to be susceptible to a variety of age-related diseases, including age-related macular degeneration (AMD).

The incidence of AMD varies a lot among different ethnic/racial populations. For example, in the United States, the likelihood of losing vision from AMD is very low for a person with an African maternal background but it is much higher in people of European descent. Similarly, in an Israeli eye clinic, of the people who had AMD, 96% were Jewish while only 4% were of Arab descent. This suggests that European mtDNA in retinal cells of Caucasians may be the reason they are more susceptible to AMD.

Mitochondria and Age-Related Macular Degeneration
Figure 1

It has been recognized that AMD is a very complex disease with many factors involved (Figure 1). There are more than 30 genes associated with AMD, representing many different biological pathways. In addition, mitochondrial damage and specific mtDNA haplogroups have been associated with AMD. Finally, it is recognized that environmental factors, such as smoking and obesity, increase the risk to develop AMD.

Although millions of dollars and thousands of man-hours have been invested in finding the causes and treatments for AMD, we still do not understand how to prevent the most common form of AMD. One major difficulty has been that when we study a diverse group of individuals, each with hundreds of different nuclear and mitochondrial genes, it is very difficult to identify the causes and pathways involved with developing AMD and determining effective treatments. One drug may not help everyone and different people develop different types and severities of AMD.

Mitochondria and Age-Related Macular Degeneration
Figure 2

Kenney’s approach to this dilemma has been to SIMPLIFY THE TESTING SYSTEM (Figure 2). In her research with different ethnic/racial groups, Kenney has found that the Ashkenazi Jewish population (K haplogroup) is an excellent group in which to study age-related diseases. This group has very well characterized nuclear and mitochondrial genes, the population tends to relatively homogenous and to marry within their community. Finally, the Ashkenazi Jewish population has longevity, which increases the likelihood that they will develop aging diseases, such as AMD.

Kenney’s laboratory has created a “cybrid” test system, which are cell lines with identical nuclei and nuclear DNA, but different mitochondrial DNA so that the differences in the cell behavior can be attributed to the different mitochondrial DNA (see the following cybrid story on 11/17/15). Using the cybrid system, Kenney has compared cell behavior of mitochondria from subjects with the K (Ashkenazi Jewish) haplogroups and the mitochondria from people of the H haplogroup (Figure 3), the most common European haplogroup.

Mitochondria and Age-Related Macular Degeneration
Figure 3

There are:

  • Major differences in production of cholesterol and lipid molecules
  • Altered levels of inflammation
  • Differences in their responses to toxic effects of amyloid-? (a toxic protein associated with AMD and Alzheimer’s disease)

These differences are important contributors to AMD and other age-related diseases.

Significance of the Findings
Maternally inherited mitochondrial DNA can influence how a person’s cells respond to stress and this can contribute to age-related diseases. This is a completely new way of thinking about common aging diseases and offers new approaches to treatment and prevention of those diseases.

Future Studies
Kenney’s laboratory will continue to use the K haplogroup cybrid model to study the mitochondrial DNA, with the goal of blocking the harmful events that cause early retinal cell death, such as that seen in AMD. An additional advantage of cybrids is that they are unique to the donor whose blood was used to make them. Therefore with these “personalized cybrids,” Kenney can test the responses of the personalized cybrids to drugs that are currently being used for AMD (Lucentis™, Avastin™ and Eylea™). They can also be used to identify novel, new drugs that can protect the cells from early cellular death, a major event in the dry form of AMD. This research shows great promise in developing personalized treatments for AMD and other age-related diseases.

11/12/15


Anthony B. Nesburn, MD  FACSAnthony B. Nesburn, MD FACS
President/Medical Director
Discovery Eye Foundation

The Importance of An Eye Exam

Why You Need An Eye Exam

The end of the year is fast approaching – when was the last time you had an eye exam? Was it a comprehensive eye exam?
eye exam
To keep your eyes healthy and maintain your vision, the American Optometric Association (AOA) recommends a comprehensive eye exam every two years for adults ages 18 to 60, and annual exams for people age 61 and older. However, if you have a family history of eye disease (glaucoma, macular degeneration, etc.), diabetes or high blood pressure, or have had an eye injury or surgery, you should have a comprehensive exam every year, unless otherwise indicated by your doctor.
Also, adults who wear contact lenses should have annual eye exams.

An important part of the comprehensive eye exam is the dilated eye exam to look inside your eye. Drops are placed in each eye to widen the pupil and allow more light to enter the eye. This gives your doctor a clear view of important tissues at the back of the eye, including the retina, the macula, and the optic nerve. This allows for early diagnosis of sight-threatening eye diseases like age-related macular degeneration, diabetic retinopathy, glaucoma, etc.

To better understand the importance of the dilated eye exam, here is a video from the National Eye Institute (NE) that explains what to expect.

At the end of your comprehensive eye exam your doctor should raise any concerns he has with you. But it is up to you to be prepared to react and ask questions for peace of mind and to help save your vision.

Questions To Ask After Your Eye Exam

It is always important to know if anything about your eyes have changed since your last visit. If the doctor says no, then the only thing you need to know is when they want to see you again.

If the doctor says the have been some minor changes, you need to know what questions to ask, such as:

  • Is my condition stable, or can I lose more sight?
  • What new symptoms should I watch out for?
  • Is there anything I can do to improve or help my vision?
  • When is the next time you want to see me?

If the doctor sees a marked change in your vision or give you a diagnosis of eye disease, you would want to ask:

  • Are there treatments for my eye disease?
  • When should I start treatment and how long will it last?
  • What are the benefits of this treatment and how successful is it?
  • What are the risks and possible side effects associated with this treatment?
  • Are there any foods, medications, or activities I should avoid while I am undergoing this treatment?
  • If I need to take medication, what should I do if I miss a dose or have a reaction?
  • Are there any other treatments available?
  • Will I need more tests necessary later?
  • How often should I schedule follow-up visits? Should I be monitored on a regular basis?
  • Am I still safe to drive?

Your vision is a terrible thing to lose, but with proper diet, exercise and no smoking, along with regularly scheduled eye exams, you improve your chances of maintaining your sight.

11/5/15

Susan DeRemerSusan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation

Best’s Disease

In 1905, Friedrich Best presented a detailed pedigree of an inherited retinal condition referred to as vitelliform dystrophy, or Best’s disease. Best’s disease is an inherited dystrophy of the macula that primarily involves cells known as retinal pigment epithelium (RPE).

best's disease
Friedrich Best

Best’s typically affects both eyes and presents itself either in childhood or early adulthood. Visual acuity is usually minimally affected early on in the course. As the condition progresses, the vision can slowly begin to deteriorate. The rate of progression or the overall amount of progression is difficult to predict. The rate of progression may be also be asymmetric, with one eye progressing at a different rate than the other. Some patients may notice the development of scotoma, or “blind spot”, in their central vision as the condition progresses. Other patients may not progress to later stages or experience vision loss. Loss of peripheral, or side vision, is not expected with Best’s.

Best's disease
Best’s disease

The diagnosis of Best’s disease is primarily based on a careful clinical exam. Taking a careful family history is also important as Best’s is typically inherited in an autosomal dominant pattern. This means that an affected individual has a 50 percent chance of passing the gene to their offspring. It should be noted though that there is highly variable expression, which means there may be some affected individuals in whom the changes are so mild that they never notice any visual disturbance. The causative gene is located on chromosome 11 and has been labeled BEST1 (VMD2). This encodes for a protein known as bestrophin 1, which is located on the membrane of RPE cells. It is believed that this protein is involved in RPE metabolism through its control of chloride channels, although the details are still being elucidated. Thus far, there have been over 200 mutations of the BEST1 gene that have been described.

The classic exam finding in Best’s is a circular yellow lesion in the macula. This lesion resembles an “egg-yolk”, and is often referred to as such by ophthalmologists. As the condition progresses, the yellow material begins to break up and the pigmentation of the macula attains a more mottled appearance. This is often referred to as a “scrambled egg” appearance. After many years, there may be evidence of cell loss in the macula, which can negatively impact the visual acuity. In a relatively small proportion of cases, a complication can occur in which abnormal blood vessels grow underneath the macula and begin to leak fluid and/or blood into the macula. This is known as choroidal neovascularization (CNV), and can be vision threatening. Fortunately , CNV can be treated effectively with medications that are injected into the eye as part of a straightforward and low-risk office procedure. Typical signs of CNV would include distortion or blurring of the vision, and it is important to notify your doctor of any sudden changes in vision.

Diagnostic testing is sometimes used to confirm the diagnosis. The electro-oculogram (EOG) is universally abnormal in Best’s, and can be a valuable confirmatory test. Fluorescein angiography and optical coherence tomography can be valuable tests to better evaluate the macula and to also look for the development of CNV. Genetic testing for Best’s is now possible as well.

There is no established medical or surgical management for Best’s disease. In patients who develop CNV as a secondary complication, existing treatment options are effective. Future avenues of therapy hold significant promise, but are in their early stages of development. Stem cell based therapies, for example, have the potential to help restore healthy cells that may have been lost during the disease progression.

10/29/15

Dr. Esmaili posterior vitreous detachmentDaniel D. Esmaili, MD
Retina Vitreous Associates Medical Group

Increased Awareness for Saving Vision

The following is a survey done by Essilor (a French company that produces ophthalmic lenses along with ophthalmic optical equipment) and a large marketing research firm in the UK, YouGov. While the focus in on people living in the UK, the results would probably be similar to the US population. Even with increased access to the Internet, many people are still not aware of the risks associated with eye disease and what they can do to help retain their vision. Increased awareness of informational resources are important for saving vision.
saving vision
There are a number of websites with easy to understand information about taking care of your vision that I have listed under Resources to Help Save Vision at the bottom of this article. And while there are eye diseases that are hereditary, you can slow the onset and progression by making good lifestyle choices about smoking, diet and exercise. Your eye care specialist is also an excellent source of information about what you can to do reduce your risk of vision loss, at any age.

Increased Awareness for Saving Vision

A YouGov poll conducted with Essilor reveals that most Britons are unaware of damage to their eyes by surrounding objects, activities, and devices. This widespread lack of awareness means fewer people seeking methods of prevention and avoidance, and for those that are aware of risks, most are not informed of existing preventative measures.

The poll has shown* that many British people remain uninformed about the various ways in which eyes are damaged by common daily factors, despite evidence that eye health is affected by blue light, UV rays (reflected from common surfaces), diet, obesity, and smoking.
Of the 2,096 people polled, the percentage of respondents aware of the link between known factors affecting and eye health were:

  • Poor diet – 59%
  • Obesity – 35%
  • Smoking tobacco – 36%
  • UV light, not just direct from the sun but reflected off shiny surfaces – 54%
  • Blue light from low energy lightbulbs and electronic screens – 29%

More than one in ten people were completely unaware that any of these factors could affect your eyesight at all.
saving vision
72% of respondents own or wear prescription glasses but only 28% knew that there were lenses available (for both prescription and non-prescription glasses) to protect against some of these factors; specifically, blue light from electronic devices and low energy light bulbs, and UV light from direct sunlight and reflective surfaces.

76% admitted they haven’t heard of E-SPF ratings – the grade given to lenses to show the level of protection they offer against UV.

Just 13% have lenses with protection from direct and reflected UV light, and only 2% have protection from blue light (from screens, devices, and low energy bulbs).

Poll results showed that younger people were most aware of the dangers of UV and blue light, yet least aware of how smoking tobacco and obesity can affect your eye health. Within economic sectors, middle to high income people are more aware of the effects of smoking & obesity on eyesight than those with low income –

  • 39% of people with middle to high income compared to 33% of people with low income are aware of the impact of smoking tobacco.
  • 38% of people with middle to high income compared to 31% of people with low income are aware of the impact of obesity.

Awareness of the impacts of smoking and obesity on eye health is significantly higher in Scotland (47% & 49% respectively) than anywhere else in the UK (35% & 33% in England and 40% & 38% in Wales).
Essilor’s Professional Relations Manager, Andy Hepworth, has commented: “The lack of awareness about these common risks to people’s eyes is concerning. Not only would many more glasses wearers be better protected, but also many people who do not wear glasses would likely take precautions too, if made aware of the dangers and the existence of non-prescription protective lenses.”

To see the full results of the poll, please visit the Essilor website.

For more information on the protection offered from blue light and UV through specialist lens coatings, for both prescriptions and non-prescription glasses, please see here for UV & Blue Light Protection options.

*All figures, unless otherwise stated, are from YouGov Plc. Total sample size was 2,096 adults. Fieldwork was undertaken between 21st and 24th August 2015. The survey was carried out online. The figures have been weighted and are representative of all GB adults (aged 18+).

Resources To Help Save Vision
All About Vision
Macular Degeneration Partnership
National Eye Institute (NEI)
Prevent Blindness

10/16/15


Susan DeRemerSusan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation

Retinal Vascular Occlusions

Just like any other organ in the body, the retina needs a healthy blood supply to function properly. When a blood vessel in the retina becomes blocked, sudden loss of vision can occur. Such blockages, known as retinal vascular occlusions, often occur in older adults. Because there are effective treatments available, seeing a specialist promptly can prevent further problems or even restore vision.

Retinal arterial occlusions

Arteries are the vessels that bring fresh blood containing oxygen and nutrients to different parts of the body. The artery that supplies the retina is known as the central retinal artery. After it enters the eye, the central retinal artery splits up into branch retinal arteries that serve different areas of the retina.

Symptoms
The symptoms of a central retinal artery occlusion include a sudden, painless loss of vision in one eye. Because the circulation to the entire retina is disrupted, the vision loss is profound and encompasses the entire field of vision. In contrast, a branch retinal artery occlusion only leads to loss of vision in a part of the field of vision. This is because only part of the retinal circulation in compromised. Similar to a central retinal artery occlusion, a branch retinal artery occlusion is also typically sudden and painless.

Evaluation
Retinal arterial occlusions can usually be diagnosed simply by examining the retina. Often, the retina is whitened in the area of the occlusion due to the lack of blood flow. Most arterial occlusions occur in patients with diseases such as high blood pressure or diabetes. On occasion, fragments of cholesterol or blood clots can be cause of the occlusion. Therefore, the treating physician will usually order tests looking for the source of these deposits in the carotid arteries or the heart. Another important cause of central retinal artery occlusions is a condition known as temporal arteritis. Temporal arteritis is an inflammatory disorder that can also produce fever, pain, or weight loss. Blood tests are ordered if temporal arteritis is suspected.

Retinal vascular occlusions
Figure 1. Whitening of the retina due to a central retinal artery occlusion

Treatment
Unfortunately, there is no proven, reliable treatment for retinal arterial occlusions at this time. Various methods including hyperbaric oxygen, ocular massage, and anterior chamber paracentesis may or may not be effective if the occlusion is treated right away. However, if the occlusion is due to temporal arteritis, treatment with corticosteroids is effective at preventing loss of vision in the other eye. An unwanted, late complication of retinal arterial occlusions is neovascularization. Neovascularization refers to the growth of new, abnormal blood vessels in different parts of the eye that can result in bleeding, detachment of the retina, or glaucoma. Neovascularization is treated with laser or injections of anti-neovascular medications into the eye.

Retinal venous occlusions

After blood has passed into the eye through the retinal arteries, it leaves through the retinal veins. Blood travels first through the smaller, branch retinal veins and then enters the central retinal vein.

Symptoms
A central retinal vein occlusion usually causes sudden, painless vision loss in one eye. Unlike a central retinal artery occlusion, which causes profound vision loss, the visual deficit in a central retinal vein occlusion can range from mild to severe. More severe occlusions cause more severe deprivation of vital oxygen to retinal tissue. In addition, a central retinal occlusion can result in macular edema, swelling of the retina that also leads to blurred vision. A branch retinal vein occlusion usually leads to blurring of vision in only part of one eye. Like central retinal vein occlusions, branch retinal vein occlusions can vary in severity, but often result in macular edema as well.

Evaluation
Retinal venous occlusions are also diagnosed by examining the retina. The blocked vein will appear dilated and engorged. In addition, the area of the retina served by that vein will contain hemorrhages or become swollen. To assess the amount of oxygen deprivation to the retina, a specialist will often recommend a fluorescein angiogram. The angiogram involves the injection of a yellow dye known as fluorescein intravenously. Subsequent photos allow visualization of the abnormal blood flow within the retina. In addition, optical coherence tomography is often performed to determine the amount of swelling within the retina.

Figure 2. A retinal vein occlusion with hemorrhages seen as the red spots in the bottom half of the image.
Figure 2. A retinal vein occlusion with hemorrhages seen as the red spots in the bottom half of the image.

Treatment
Treatment of retinal venous occlusions is largely aimed at decreasing swelling in the macula in hopes of improving vision. Currently, the most effective treatments involve injections of medication into the eye. FDA approved medications such as Lucentis and Eylea, that target abnormal levels of growth factors in the eye, can result in significant gains in vision in approximately two thirds of patients with branch retinal vein occlusions and half of patients with central vein occlusions. In addition, injectable steroid medications such as Ozurdex can also be effective, with approximately one third of patients having a significant visual gain. Laser can also be used to treat macular edema due to branch retinal vein occlusions. Keep in mind that these treatments likely need to be repeated on a routine basis or used in combination to achieve maximum benefits. If neovascularization occurs, it is treated as previously described in the section about retinal arterial occlusions.

In conclusion, occlusions of either retinal arteries or veins can cause significant visual impairment. Prompt evaluation and ongoing treatment with a retinal specialist can often improve and maintain vision.

9/24/15

Liao - Macular Pucker and Macular HoleDavid Liao, MD, PhD
Retina-Vitreous Medical Group