Glaucoma Eye Doctors Study on High Pressures and Early Treatment

May 14, 2009 By Leave a Comment

The Ocular Hypertension Study was the first well documented research to justify treatment of patients with high pressures in the eyes. After years of unvalidated therapy the results were conclusive, early treatment was preventative. Ironically, today intraocular pressure has become less definitive measure for glaucoma as blood flow disruptions to the optic nerve appear to be more important. The ocular hypertension treatment study is still groundbreaking research that means patients with high pressures should be treated sooner to prevent the development of glaucoma. Furthermore, early treatment has been shown in some cases to reverse early damage that can be detected by analyzing the nerve fibers inside the eye.

Results–Ocular Hypertension Treatment Study (OHTS)

Background

Glaucoma is a group of diseases that can lead to damage to the eye’s optic nerve and result in blindness. Open-angle glaucoma, the most common form of glaucoma, is one of the leading causes of blindness in the United States and the number one cause of blindness among African Americans. Glaucoma usually has no early symptoms, and by the time people experience problems with their vision, they usually have lost a significant amount of their sight.

How Open-Angle Glaucoma Develops

Increased pressure inside the eye is an important cause of open-angle glaucoma. In the front of the eye is a space called the anterior chamber. A clear fluid flows continuously in and out of this space and nourishes nearby tissues. The fluid leaves the anterior chamber at the angle where the cornea and iris meet. When the fluid reaches the angle, it flows through a spongy meshwork, like a drain, and leaves the eye.

Open-angle glaucoma gets its name because the angle that allows fluid to drain out of the anterior chamber is open. However, for unknown reasons, the fluid passes too slowly through the meshwork drain. As the fluid builds up, the pressure inside the eye rises. Elevated eye pressure can damage the optic nerve; a healthy optic nerve is necessary for good vision. When the optic nerve is damaged from increased pressure, glaucoma — and vision loss — are the result.

At first, open-angle glaucoma has no symptoms. People are not aware that glaucoma is affecting their vision, and there is no pain. When glaucoma remains untreated, people may notice that although they see things clearly in front of them, they miss objects to the side and out of the corner of their eye. Without treatment, people with glaucoma may find that they have no side vision. Over time, the remaining vision may decrease until there is no vision left.

The Ocular Hypertension Treatment Study

Prior to the Ocular Hypertension Treatment Study, there was no clear evidence as to whether reducing elevated pressure in the eye would delay or prevent the onset of glaucoma. Elevated pressure in the eye, a common condition affecting three to six million people in the United States, is thought to be the leading risk factor for development of open-angle glaucoma. For the purposes of this study, ocular hypertension — which can be diagnosed by an eye care professional — was defined as pressure of 24 mm Hg or greater in at least one eye.

Despite the lack of convincing evidence, approximately 1.5 million people in the U.S. with elevated eye pressure and no glaucoma damage are being treated with medications that lower this pressure. There was a need for a well-controlled clinical trial to determine whether medical reduction of elevated intraocular pressure could delay or prevent the onset of glaucoma. The resulting data would enable clinicians and patients to make rational choices and health care planners ensure that medical resources were being allocated in a safe and cost-effective manner.

The primary goal of the Ocular Hypertension Treatment Study was to determine whether reducing elevated eye pressure delayed or prevented the onset of glaucoma and subsequent vision loss in people at risk of developing the disease. Patient recruitment took place between February 28, 1994 and October 31, 1996. A total of 1636 individuals were selected to participate; 817 were assigned to receive topical ocular medication (eye drops), and 819 were assigned to observation. All of the medications used in the study were commercially available.

Scientists found that eye drops used to reduce pressure inside the eye were effective in delaying the onset of primary open-angle glaucoma. After five years, researchers found that treatment reduced the onset of primary open angle glaucoma by more than 50 percent.

The Ocular Hypertension Treatment Study is the first large-scale study to demonstrate that lowering eye pressure — a risk factor for the development of primary open-angle glaucoma — can safely and effectively delay and possibly prevent the disease.

High Risk Factors for Glaucoma

In a companion paper, also published in the June 2002 issue of Archives of Ophthalmology, the authors report finding several factors predictive of those who developed primary open angle glaucoma. These included personal risk factors, such as older age and African descent, as well as ocular risk factors, such as higher eye pressure, certain characteristics in the anatomy of the optic nerve, and thinness of the cornea. The authors note that “corneal thickness provides new information about the risk of developing primary open-angle glaucoma and we recommend its measurement in the clinical evaluation of patients with ocular hypertension.”

The authors also point out that the predictive factors for glaucoma, as identified in the Ocular Hypertension Treatment Study, “are most likely to be helpful for assessing the risk of patients who resemble the study participants, i.e. ocular hypertensive individuals with eye pressure between 24 and 32 mm Hg and no evidence of glaucoma damage.” Only about two percent of Americans have these high levels of pressure in at least one eye.

The authors conclude by saying that the study results “suggest that a clinician caring for an ocular hypertensive patient can assess that individual’s risk” for developing glaucoma by considering age, race, eye pressure, optic nerve anatomy, and central corneal thickness. By considering these factors, “the clinician can identify patients who are at moderate to high risk for developing [glaucoma] and who are more likely to benefit from early medical treatment,” the authors state.

This page was last modified in October 2008
Filed Under: glaucoma, pimary open angle glaucoma Tagged With: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Glaucoma,LASIK,Fort Collins Eye Doctor

May 9, 2009 By Leave a Comment

Should LASIK be performed on patients with pre-exsisting glaucoma? The answer is not clear to this Fort Collins Eye Doctor. Most Optometrists would have a hard time committing to a single answer. Read my post at “http://lasikfortcollins.com/”>LASIK Fort Collins.

Filed Under: Common Eye Questions for Your Optometrist, Fort Collins Eye Doctor, Fort Collins Optometrist, Fort Collins-Fun Things To Do, glaucoma, Vision Service Plan -VSP Tagged With: , , , , , , , , ,

Eye Doctors Pinkeye Recommendations to Prevent Spreading Eye Infections and Alternative Treatments

April 24, 2009 By Leave a Comment

A number of years ago an outbreak of pink eye in a elementary school had all the moms frantic and half of the school would be missing in action shortly after the announcement was sent home. Those days were prior to the education parents and health care providers have been receiving in current times about preventive measures to help in ceasing the spread of pink eye. In the past if one child was infected by pinkeye it was not long before half the class ended up with it too. Now that personal hygiene is taught more extensively in the schools at an earlier age parents are becoming more aware of how to prevent further infection of pink eye at home. This has helped seclude outbreaks so they occur less frequently than previously. It is still not unheard of to occasionally see a major outbreak spread rapidly through a school. Pink eye can cause any parent concern when they see their child come home from school with a pink to extremely red eye. Hemorrhagic forms of pinkeye cause small amounts of blood to spread out over the white part of the eye and the appearance exceeds their actual capacity to damage eyesight. The first scare is eye damage. Thankfully, pink eye rarely causes any long-term eye vision damage and some types of pink eye can resolve without any treatment in a week or so.

Pinkeye, otherwise known as conjunctivitis is an inflammation of the conjunctiva that can be caused by infections, allergies, viruses, colds, bacteria, or a substance that irritated the eye leading to an infection. Just because some pink eye types will fade away without intervention, never risk a your childrens sight with that thought process; always seek out medical eyecare from your family Optometrist immediately. Some forms of pinkeye can be debilitating for up to a year. Other more serious eye diseases may look like pinkeye but indeed may be a very serious type of eye disease. Most schools will not let your child return to school unless you can show proof that you have seen one of the Eye Doctors in your area. Your Optometrist can give your child a clean bill of health when they feel like they are no longer contagious. Unfortunately, this is not an exact science but a reasonable enough guess to significantly reduce the spread of pinkeye today. Typically a child will need to be out of school for 3-4 days.

Newborns born with pink eye is generally due to the mother passing on an STD (sexually transmitted disease) to the infant through the birth canal and can be serious if not caught at onset. Doctors have become more then vigil in checking birth mothers prior to birth for STDs that can cause serious side effects in their newborn well prior to delivery and treat those conditions during her term. Pinkeye presents with symptoms of eye discomfort, commonly relayed as feeling as if sand is in the eye. It can commonly cause the child to wake in the morning with a thick crust that seals the lids together resulting in the need of a warm towel to soften the mucus to be able to open the eye comfortably. Other common symptoms are sensitivity to light, itchiness, and excessive tearing. Pinkeye caused by bacteria or a virus are highly contagious and can be passed through touching an infected child, touching something an infected child has touched, coughing, and sneezing.

To prevent the spread of pink eye keep your child out of school or daycare until your doctor or Optometrist give the go ahead for them to return. Teach your children to wash their hands frequently and explain to them why it is so important. Washing hands while singing the happy birthday song twice to themselves is a good way to teach them correctly. Also, teach your children not to share personal care items with another student or child as well as if they are aware that another child is ill or has a case of pink eye. Do not use or touch anything belonging to that child until they have been given a clean bill of health. This is especially true in young contact lens wearers; your child should never try on another persons lenses or borrow their case or contact lens solutions. In your home, wash pillowcases regularly, especially anytime your child is ill as well as other bedding and linens. If your child has a case of the pink eye, separate their towels and washcloths items from the rest of the families and wash their items in hot water. If your child is at risks of coming down with pinkeye due to allergies, limit their pollen contact by keeping your child inside on heavy pollen days, keep your home closed up during them periods, dust and vacuum daily, and avoid subjecting your child to any other free radicals in the air such as cigarette smoke, smog, car exhaust, etc. If you suspect your child may have a case of the pinkeye or a school nurse has sent your child home, contact a qualified Optometrist to get treatment as needed for your child.

Alternative treatments for pinkeye in under developed countries include topical povidone-iodine (betadine) which is effective against most bacterial conjunctivitis at a fraction of the cost of standard antibiotic prescription eye drops. Povidone is sometimes used by optometrists to treat EKC, a special severe from of viral conjunctivitis. However, it does not appear to be a treatment for most viral forms of conjunctivitis. Homeopathic remedies include Similasan Pink Eye Relief eye drops. Similasan 2 Allergy Eye Drops have had one small study showing effectiveness and they do seem to work well for some patients with milder forms of allergic conjunctivitis. Any over the counter eye drop treatments should be used under medical supervision as some drops can induce angle closure glaucoma in susceptible patients. There have been cases where individuals have gone blind from self treating with over the counter eye drops. Chronic dry eyes can make you susceptible to recurring bouts of conjunctivitis. Treatment of dry eyes may be a very good preventative measure for chronic pinkeye

Filed Under: Corneal Infections, Dry Eyes, Eye Diseases, Eye Symptoms, Eye Vitamins, Fort Collins Eye Doctor, Fort Collins Optometrist, glaucoma, Pinkeye, Stinging Eyes, Vision Service Plan -VSP Tagged With: , , ,

Glaucoma Eye Symptoms

April 21, 2009 By 1 Comment

What are the symptoms of glaucoma?

Until the eye disease has progressed to a fairly advanced stage there are no symptoms noticed by patients except in the small subgroup of glaucoma from angle closure. In many cases over half of the optic nerve fibers may have been lost before any symptoms are noticed. Narrow angle glaucoma does cause eye pain but 95% of glaucoma patients have the other form referred to as primary open angle glaucoma which has symptoms of pain only in very late stages in the rare cases where treatment has failed.
However, as the disease progresses, a person with glaucoma may notice his or her side vision gradually failing. Objects in front may still be seen clearly, but objects to the side may be missed.

When glaucoma treatment fails and large amounts of vision have been lost patients will start to notice deficits in there side vision. This usually occurs when glaucoma has been diagnosed at a late stage due to lack of regular eye health check-ups or when patients skip medications on a frequent basis. Without treatment, people with glaucoma will slowly lose their peripheral (side) vision until they are left with a tunnel of vision. With time, even that will diminish until complete blindness occurs.

Because there are no real symptoms, early detection through routine eye examinations is an essential part of your preventative health care.

Filed Under: Eye Symptoms, Fort Collins Eye Doctor, Fort Collins Optometrist, glaucoma

Eye Doctors Find Red, Swollen Morning Eyes Are Not Always Serious Problems Like Glaucoma Or Dry Eyes

April 20, 2009 By Leave a Comment

Red eyes and swollen eyelids upon awakening in the morning are common eye problems that many people suffer from with vague diagnoses usually of dry eyes or eye allergies. Sometimes just having the eyes dilate in the darkness can precipitate attacks of angle closure glaucoma in patients who have risk factors for this type of glaucoma. Frequently eye allergies are the cause, aggravated by a low level of tears in dry eyes. The lower level of tears means allergens your eyes are exposed to at night are not as diluted as a normal eye and they have a greater effect. Open windows in allergy season allow more pollen inside, and pets sleeping on pillows during the day can also add to the problems. Sleep apnea along with floppy eyelid syndrome can cause your eyes to be open and dehydrate while you sleep. A low-grade infection of the eyelid margins with staphylococcus bacteria is another common cause of swollen eyelids in the morning. Many other conditions can cause red, swollen eyes in the morning. However, there are normal aging factors that predispose you do this condition that is found more frequently in women than men.

As you sleep at night the normal tear film is not being pumped out through the tear ducts and spread across the eyes by the wiper like motion that occurs with normal blinking. In the REM states of sleep you do have some blinking occurring but overall the eye is a static environment while you sleep trapping bacteria on the surface of the eye. The eye has it’s own immune system that is ramped up at night to compensate for this increase in bacteria. The result is a state of mild inflammation is almost everybody. As the body ages and the eyes become dryer the relative concentration of bacteria and bacterial toxins increases making a more noticeable immune response. With menopause, there is a drop in hormone levels in both men and women. The androgen hormone that is more commonly associated with men seems to be the largest factor in dry eyes in women. The incidence of dry eyes in women is at least 3-4 times more commonly reported and also increases with age.

The eyelid anatomy contributes to eyelid swelling. There is a barrier to fatty tissue in the upper eyelid that degrades with age and fatty tissue enters into the lid causing it to droop all of the time. The eyelid tissue looses its elasticity with age and thins resulting in more susceptibility and visibility of swelling. Sleeping at night without blinking with the buildup of inflammation described above causes swelling in the adjacent eyelid tissue. Since you are lying down with a slight elevation to your head there is reduced drainage of fluid within the lymph system and fluid accumulates on the lower eyelid. This will reduce throughout the day if the cause is chronic low-grade inflammation overnight.

The first step in treatment is a visit to your eye doctor to rule out any other more serious causes such as heart conditions, kidney problems, obstructive sleep apnea,glaucoma, or medication side effects. Your optometrist may find other causes as outlined above that need to be treated. After that, there are a few alternative therapies you can try to help.

1. Reduce alcohol and salt consumption as they contribute to water retention

2. Try some form of cool compresses in the morning for 5-10 minutes.

3. Exercise early in the morning to stimulate the circulation.

4. Be glad your vision is good and your eyes are essentially healthy!

Filed Under: Corneal Infections, Dry Eyes, Eye Diseases, Fort Collins Eye Doctor, Fort Collins Optometrist, glaucoma, Pinkeye Tagged With: , , , , , , , , , , , , , , , , , ,

Glaucoma-What to Expect in a Visual Field Test

April 14, 2009 By Leave a Comment

Visual field testing is done for a number of different reasons but most frequently to test or manage patients who have glaucoma. So just what is this test that your Eye Doctor wants you to have? It may be referred to by different names; automated perimetry, visual field test, threshold test, SITA (slang for Swedish Interactive Thresholding Algorithm) or various other terms. The original testing method was called a tangent screen which is a black square of material hanging on the wall.. The Goldmann Bowl Perimeter was next and it was a manual version somewhat like the automated devices your eye doctor uses today. Your sensitivity to light on the retina (the light sensitive layer lining the inside of the eye) resembles a topographical map of a hill. The most sensitive point is in the center like the high point on a hill and the farther you move away from this central vision point the less sensitive the tissue is to light (like the lower elevations on a topographical map). The central high point corresponds to the macula, which is why macular degeneration only has to compromise a small area to have devastating effects on vision. A visual field test measures the eyes sensitivity out into the peripheral parts of the retina. Most eye exams only test the small central peak of the hill. The visual field test measure not only the peripheral retina but to some extent the pathway of the eye nerves through the brain.

Your visual field test will be either a screening test or a threshold test. Screening test are used by an Optometrist to check for eye diseases and vision problems in a methodology similar to how your family doctor would do a single blood pressure reading to screen for high blood pressure. If your family doctor was more concerned they would want multiple readings and more refined testing methods, perhaps a cardiac stress test to see how your heart and blood pressure performs under different conditions with a much higher number of data points. Likewise, a threshold visual field test done by your eye doctor is much more detailed testing. Since the hill of vision shrinks with age, a threshold test will compare your results to an age matched population sample without glaucoma and other eye diseases. The eye test will yield a detailed statistical analysis. You can expect to the test to take about 3 to 5 minutes for each eye in most cases. The vision test is standardized for eyes that are dilated so you will need to plan on 30 to 60 minutes in the office even though the visual testing itself is fairly brief. For the actual visual field test you will be seated with a half of a bowl like instrument in front of you. If you wear contact lenses they will need to be removed. The visual field instruments calculate a different prescription compensating for the distance you are viewing. Prescription lenses are placed in a holder in front of your eyes to substitute for your contact lenses or eyeglasses. One eye will be covered and you will need to fixate on a central light throughout the testing. A device resembling a computer mouse will be held in one hand and you simply click it each time you think you see a small point of light flash anywhere in the bowl. The flashes are very brief and may be close to the point your eye is fixating on or very far off in the peripheral field of sight. The brightness of the flash of light also varies from very dim to very visible. In our Eye Center we usually start the testing sequence in demonstration mode to familiarize patients with the process. Many people worry about their responses; if they clicked too late, clicked accidentally, and are uncomfortable with the dimness of some light points just on the edge of visual perception. This should not be a concern. Visual field testing is vary sophisticated today and measures your mistakes, retests them, and gives an index telling us how much variation there was in your eye exam. If the reliability is too low we repeat the test on another day and almost always find the reliability of the eye exam goes up to acceptable levels. There are even adjustments made by the software to factor out the fact that you may have cataracts or other conditions that are not in the retina or visual pathway through the brain. With most visual field instruments you can pause the test yourself by holding down the clicker. That can give you a chance to relax, change position, or ask a question to clarify what you responses should be. We usually start on a demonstration mode to familiarize patients with the process and change over to actual testing once patients appear to be comfortable. You can always request a demonstration period first. Besides glaucoma, a visual field test can be used to diagnose pituitary tumors, neurological problems, and unexplained loss of sight and headaches. Your vision insurance plan services may cover visual field testing or it could fall under your medical policy. One last point- if you live in area like Fort Collins the Colorado sunshine is extremely bright after your eyes are dilated. Be sure you leave with temporary sunglasses if you don’t already have quality sunwear.

Filed Under: Common Eye Questions for Your Optometrist, Contact Lenses, Eye Symptoms, Flashes, Floaters, Fort Collins Eye Doctor, Fort Collins Optometrist, glaucoma, Vision Service Plan -VSP Tagged With: , , , , , , , , , , , ,
Newer Posts »
SN Google Plus