Study Links Myopia with Higher Glaucoma Risk

In a recent study, researchers concluded that people with myopia may have twice the likelihood of developing glaucoma, the world’s leading cause of blindness.

Myopia is the condition of being nearsighted, that is, being able to see close objects clearly but having trouble seeing far objects. Myopia occurs when the eyeball is too long or the cornea too curved, making your eye unable to correctly focus light at certain distances. Nearly 1/3 of all U.S. residents are nearsighted.

In the study, researchers in the Netherlands analyzed a collection of studies previously published in Ophthalmology. They kept track of who had myopia and who had glaucoma out of the tens of thousands of people included in the studies, and they found that nearsighted people were around 90% more likely to develop acute angle glaucoma. They also found that those with higher myopia had a higher risk of glaucoma. Though ophthalmologists recommend regular eye exams after age 40, researchers recommended that nearsighted people, no matter what age, should have annual eye exams.

While this study draws alarming conclusions for nearsighted people, the U.S. Preventative Services Task Force says it provides too little evidence to change the recommendation for eye exams.

One problem with the study is that it shows only that there may be a relationship between myopia and glaucoma, not that myopia causes glaucoma. The researchers make no claims to understand how a misshapen eyeball could cause damage to the optic nerve which results in blindness. The study also collected data from studies analyzing people of different ages and ethnicities, and it is hard to make generalizations about relationships between conditions over such a broad spectrum of people.

Though this study is not conclusive, it is worthwhile for myopic patients to be aware that they may have a higher risk of glaucoma. If you have myopia and wish to learn more about glaucoma risks and prevention, please contact an experienced ophthalmologist in your area today.

Researchers See Additional Benefits of Vitamin C

The benefits of vitamin C are not just limited to your immune system and the orange juice industry. According to the results of a recently published study, vitamin C is vital for your eyes—and maybe even your brain—to function properly.

Researchers at Oregon Health & Science University discovered that the retinal cells need relatively high doses of vitamin C. Scientists believe that the antioxidant properties of vitamin C helps preserve the receptors and cells in the retina from premature breakdown.

“Because the retina is part of the central nervous system, this suggests there’s likely an important role for vitamin C throughout our brains to a degree we had not realized before,” said Henrique von Gersdorff, Ph.D, a senior scientist at the OHSU Vollum Institute and coauthor of the study, which appeared in the June 29 issue of the Journal of Neuroscience.

The brain has receptors known as GABA receptors, which are involved in transmissions between brain cells and act as inhibitors to neurons to which they bind. The OHSU research team found that these receptors stopped working properly when vitamin C was removed.

Although the overall function of vitamin C in the brain is not well understood, vitamin C tends to remain in the brain longer than other areas of the body. Researchers believe their findings could impact diseases such as epilepsy and glaucoma, which are the result of nerve cell dysfunction in the retina and brain that occur in part because of improperly working GABA receptors.

“For example, maybe a vitamin C-rich diet could be neuroprotective for the retina—for people who are especially prone to glaucoma,” von Gersdorff said in the Journal of Neuroscience. “This is speculative and there is much to learn. But this research provides some important insights and will lead to the generation of new hypotheses and potential treatment strategies.”

If you would like to learn more about glaucoma treatment options, please contact an eye doctor in your area.

Wipe-Out: A Serious Complication of Glaucoma Surgery . . . Or Not

If you are suffering from glaucoma and eye drops have not helped to sufficiently lower your intraocular pressure (IOP), surgery becomes your next treatment option. However, in considering glaucoma surgery, you may have come across the risk that you may face a “wipe-out” of your central vision after surgery. You are then faced with a hard decision: accept that your vision will slowly be eroded from the edges by glaucoma, or risk that the cure for glaucoma may eliminate your central vision, including macular vision responsible for detailed sight. This may give you pause, but it should not give you too much pause, because the “wipe-out” phenomenon is controversial, and many ophthalmologists believe it is little more than a myth or artifact of primitive techniques in the diagnosis and treatment of eye diseases and conditions.

Wipe-out has its roots in the earliest history of glaucoma surgery. The developer of glaucoma surgery, Albrecht von Graefe reported that after surgery patients might experience a loss of central vision, especially when surgery was performed on patients with advanced glaucoma. In 1957, one prominent ophthalmologist said that a patient whose visual field has been reduced to 15 degrees or less should not have surgical treatment because of the risk of central vision loss.

However, it was also at this time that some surgeons began to dispute whether central vision was ever lost as a result of glaucoma surgery. This faction has been gaining ground in recent years. Most cases of wipe-out occurred before the introduction of sophisticated diagnostic tools, such as optical coherence technology, which could have detected macular damage that would easily be missed by earlier ophthalmologists. Other potential victims of wipe-out had other visual conditions that could have accounted for vision loss, such as hypotony (low IOP), uveitis, and cystoid macular edema.

The only relatively recent study to report wipe-out was published in 1993. This study noted 4 cases of wipe-out in 508 eyes that underwent trabeculectomy (the most common form of glaucoma surgery), and the authors affirm their results prove the existence of the condition. These patients had several additional risk factors, including advanced age (average age of 82), split fixation of the central visual field, severe hypotony after surgery, and more cardiovascular disease, so it’s possible that wipe-out actually exists and is related to one of these four factors.

While wipe-out may actually exist, it is at best a rare phenomenon with very low risk of vision loss. Untreated glaucoma, however, will lead to vision loss as surely as night follows day, making surgery a better option in most cases when your vision is threatened.

Before deciding on glaucoma surgery, however, you should discuss the possibility of vision loss after surgery, which can come from many factors. Contact a local ophthalmologist today to discuss the risks and benefits of various glaucoma treatment options.

New Research Points to Genetics as the Cause of Glaucoma

Glaucoma is a disease that affects more than 16 million people world-wide, causing irreparable blindness in a fourth of those with this condition. The term “glaucoma” encompasses many variations of this condition that involves loss of peripheral, or wide-angle, vision. Doctors know that pressure in the eye causes damage to the optic nerve which in turn causes vision impairment.

However, new research has found that genetic mutation is the underlying cause of glaucoma. A Swedish, Tunisian, and American collaborative study found, in summary, that a gene mutation decreasing the size of people’s eyes leads to increased intraocular pressure and therefore glaucoma.

The researchers first identified this mutation in mice.  These mice had smaller eyes than regular mice but the same size lenses. When their pupils dilated, their irises crowded into the corners of their eyes, increasing their intraocular pressure dramatically.

Researchers then studied several Tunisian families who suffered from glaucoma and found the same gene mutation.

Previously, doctors have had no good way to test people for glaucoma, and many times they can’t detect it until patients begin losing vision. This study and others like it provide a more efficient and direct way to screen people for glaucoma. Instead of guessing who will get glaucoma and who won’t, doctors can identify people who carry this “glaucoma gene” which may place them at a higher risk of getting the disease. Hopefully the results of this and other studies can help stop the progression of glaucoma and prevent blindness.

If you suffer from glaucoma of have more questions, please contact an ophthalmologist in your area to schedule an appointment today.

How Does Age Affect Glaucoma?

Glaucoma is one of the most common causes of blindness among Americans. Studies have consistently shown that the older a patient is, the more likely they are to suffer from this debilitating eye disease. However, no good answer has been given as to why it continues to increase in the elderly population.

While there is an exponential increase in glaucoma among older patients, there is no correlating increase of the internal eye pressure that doctors believe is the primary cause of glaucoma. This has led many doctors to re-evaluate what factors might be directly causing glaucoma in the elderly.

Two theories currently dominate:

  • The outflow of the eye is steadily decreasing as patients age
  • The optic nerve is becoming more susceptible to pressure fluctuations as patients age

Whatever the case, the onset of glaucoma among the elderly should not be taken lightly. Early detection of glaucoma is the best possible way to prevent vision loss. You should ideally be tested for glaucoma every year once you reach the age of 40.

If it has been too long since you had a proper glaucoma screening, don’t hesitate to contact a local ophthalmologist today and schedule an eye exam. Protecting your vision now will enable you to enjoy it for years to come.

Laser Glaucoma Surgery Questions

What are my options for laser glaucoma surgery?

Depending on the type of glaucoma you have, your options for laser glaucoma surgery include laser peripheral iridotomy, and laser trabeculoplasty. Laser trabeculoplasty includes argon laser trabeculoplasty, selective laser trabeculoplasty, and micropulse laser trabeculoplasty. The method most suited to your needs will be determined by your ophthalmologist.

Are there risks with laser glaucoma surgery?

All surgeries have some risks. Surgical risks like bleeding and infection may occur, but are very rare. A risk specifically related to laser glaucoma surgery is a temporary increase in intraocular pressure. This will be carefully monitored by your eye surgeon in the days following your procedure.

Is laser glaucoma surgery permanent?

Glaucoma can be treated, but not cured. Laser glaucoma surgery can greatly reduce the pressure in your eyes and reduce your risk for future vision disorders, but it may need to be repeated in the future. Eye drops and oral medications may also be required to continue outflow of fluid from your eyes.

Why should I consider laser glaucoma treatment?

No two treatment options are ideal for every patient, but glaucoma must be treated. Left untreated, glaucoma will eventually lead to blindness. Working closely with an eye doctor in your area, you can determine what method of glaucoma treatment is best for you.

If you have questions about laser glaucoma surgery, please locate an experienced ophthalmologist in your area through www.eyes.com to schedule an initial consultation today.

Questions about Glaucoma

What are the different types of glaucoma?

There are two types of glaucoma, open angle glaucoma and angle closure glaucoma. Open angle glaucoma is more common and often produces no noticeable symptoms. Angle closure glaucoma can be painful and lead to rapid vision loss.

What are the symptoms of glaucoma?

Open angle glaucoma may be asymptomatic. In many cases, increased pressure in your eye can only be detected during your regular eye exams. Angle closure glaucoma may produce pain, redness, halos around lights, and nausea. Both types of glaucoma can lead to complete vision loss if left untreated.

What are the treatments for glaucoma?

Treatment for glaucoma can include eye drops, oral medications, or laser treatments that reduce pressure in the eye. The severity of your glaucoma will determine the method most suited to treat your glaucoma.

Is there a cure for glaucoma?

Glaucoma can be treated but there is not currently a cure. There is no evidence to suggest that lifestyle has any impact on glaucoma. People over the age of 60, or with certain medical conditions may be at higher risk, but glaucoma can also be present at birth or develop during adolescence. In the absence of a cure, treatment options can provide necessary pressure relief to help avoid blindness.

If you have questions about glaucoma or would like to schedule a glaucoma screening, please locate an experienced ophthalmologist through www.eyes.com in your area to schedule a vision examination.

Stable, Self-Renewing Stem Cells May Lead to Treatment for Glaucoma, AMD

Ideally, vision screening will help people identify glaucoma before suffering significant amounts of neural cell loss. But if people suffer significant vision loss due to the death of optic nerve cells in glaucoma or the loss of nerve cells due to age-related macular degeneration or retinitis pigmentosa, what will people do?

Currently, there is no way to replace lost neural cells, either in the brain or in the eye, no matter the cause of the loss. However, researchers at the Institute for Genomic Medicine at the University of San Diego seem to be developing a promising angle for treatment. Researchers at the University have created a colony of stable, self-renewing neural stem cells derived from human embryonic stem cells.

The process works by taking the embryonic stem cells and exposing them to a precise sequence of chemicals to cause them to develop into neural precursor cells, but then stopping before the cells further differentiate.

The new cells can be differentiated into a number of types of neurons, including eye-specific neurons. The head researcher is also a professor at the Shiley Eye Center, and has directed the research with a focus on degenerative eye diseases. Also important, the new stem cell colony does not seem to have an increased risk of developing into tumors as some previous embryonic stem cell lines have shown.

Even more exciting, the method used to create the stable colony can be used to induce a transformation of pluripotent stem cells (so-called “adult stem cells”) into neural stem cells, which may allow those of us currently facing these degenerative diseases to see treatment in the future.

However, for now the main option for glaucoma treatment remains to prevent damage to the optic nerve by diagnosing elevated intraocular pressure early. You should regularly visit your eye doctor for glaucoma screening. If you do not currently have an eye doctor, please contact a local ophthalmologist today.

Developmental Error Leads to Juvenile Cataracts

According to research published in the March 25 issue of Science, researchers have shown that RNA granules, which help control the function of messenger RNA (mRNA) can contribute to the development of juvenile cataracts and may also have a causal impact on glaucoma as well.

The discovery was made independently by two teams of researchers working in different fields. One team identified a malfunctioning gene in mice that did not build an essential protein, leading to defects in the eye’s crystalline lens. Mice that did not have the protein developed cataracts, elevated intraocular pressure, and optic nerve damage.

Then the team learned that a second team had also identified the same genetic defect in children suffering from pediatric cataracts. All of the children with this gene also developed glaucoma after cataract lens extraction.

The gene in question performs two relevant roles. First, it is expressed in lens fiber cells and performs important regulation duties in ensuring the normal development of the eye’s clear lens. Second, the gene helps produce stress granules in response to oxidative stress. Normally, these stress granules help protect the cell, but without them, the cells become vulnerable to oxidative stress. Oxidative stress damage has been linked with damage to the drainage structures in the eye, which can contribute to glaucoma.

Although researchers note that additional research is required to link the genetic defect with glaucoma, they hope their work will provide an important start for understanding juvenile cataracts and may ultimately help protect children from the condition before surgery is required to remove the clouded lens, which puts them at additional risk for glaucoma.

To learn more about cataracts and glaucoma, please talk to a local ophthalmologist today.

At-Home Glaucoma Tests: Do They Work?

You may have heard about at-home glaucoma tests, but, are they FDA-approved, do they actually work, and what can they actually tell you?

FDA approval generally means that a medical treatment has been rigorously evaluated by the Food and Drug Administration. To get approval, a treatment or device must present a number of clinical studies to support the assertion that the device in question is both safe to use and an effective treatment. The online glaucoma test offered by Peristat Group is not FDA approved, it is only FDA-cleared. FDA clearance generally constitutes a much less rigorous evaluation of the device, most often to assess whether the device is “substantially equivalent” to a device already in use. For the at-home glaucoma test, the pre-existing technology is a similar test used in doctor’s offices.

Does it work? According to the Peristat Group, the test is 90% accurate when compared to the doctor’s office version. This success rate is not bad when you consider the significant cost savings. The at-home test requires just your computer and internet access, and costs only $29.95 per evaluation (with a possible discount if you purchase a package), much less than the cost of going to the doctor’s office, unless you have some pretty swanky insurance coverage.

But another important question is: what can an online glaucoma test actually tell you? The online test works attempting to measure your visual acuity at all points in your visual field. The test asks you to focus on a white dot at the center of the screen, then presents you with a set of stimuli dots in measured locations at certain contrast settings designed to test the status of your optic nerve. The test results are then reviewed by perimetry specialists and emailed to you. Depending on the results, you may be referred to a follow-up with your ophthalmologist.

The good news about this at-home test is that it can actually identify when you’re experiencing damage to your optic nerve. Glaucoma slowly erodes your vision from the periphery, and many people do not become aware of the vision loss until it is highly advanced. This test can identify vision loss early so you can get treatment.

What this glaucoma test cannot do, though, is detect conditions that may lead to glaucoma before vision loss occurs. This includes elevated intraocular pressure, a narrow angle, or pigmentary dispersion syndrome. Detecting all these conditions requires regular visits to an ophthalmologist who can examine your eyes in person.

Find a local ophthalmologist who can screen you for glaucoma risk.