What is amblyopia?
Amblyopia commonly referred to as "lazy eye" is a condition in which the vision center of the brain fails to development properly usually for one eye. The condition if not corrected by about 11 years of age is difficult to impossible to correct. Causes for amblyopia vary including eye trauma, uncorrected unequal vision nearsightedness or farsightedness or astigmatism, congenital cataracts, or strabismus (crossed eye). The extent of vision loss can be dramatic to mild depending on the severity of the underlying problem. People with amblyopia lack stereopsis impairing their ability to judge distances. It is important that young children have their eyes examined by the age of 2 or 3 in order to provide effective treatment options. Treatments can consist of patching the "good" eye or using atropine in the good eye (causes dilation of the pupil thus blurring vision) forcing the weak eye to be used. In cases where refractive error is the cause, glasses may be required to correct the vision. In other cases surgery may be required.
What is nearsightedness?
Nearsightedness, technically myopia, is a condition where the eye is too long or the cornea to steep causing images to focus in front of the retina. This causes blurred distance vision such as reading highway signs but close vision for reading and sewing is usually normal. Children complaining of not being able to see the blackboard at school should be check for myopia. Myopia is an inherited problem and therefore usually runs in families. Individuals with myopia generally experience a worsening of the condition through their teen year usually stabilizing in early adulthood. Corneal refractive therapy (CRT), an orthokeratology-like procedure approved by the FDA in 2002, lets you wear cornea-shaping lenses at night, so you have daytime vision without contacts or glasses.
What is farsightedness?
Farsightedness, technically called hyperopia, is a condition in which the length of the eye is too short for the focal length of the lens (cornea is flatter than normal), causing images to focus behind the retina rather than on it. The result is blurred near vision. Symptoms of farsightedness include headaches and eyestrain when working or reading at close range and in extreme hyperopia at great distance. If your prescription has positive numbers for the diopter reading you are farsighted. Young children can compensate for hyperopia through accommodation (adjusting their lens) however this ability decrease with age. Also children can "grow" out of hyperopia as their eyes grow and lengthen as they mature.
What is macular degeneration and how do dry and wet versions differ?
Macular degeneration sometimes called age related macular degeneration (ARMD or AMD) is the leading cause of blindness in the world. AMD is caused by the breakdown of the macula which is the part of the retina responsible for your central or direct vision. AMD has two varieties, wet and dry. The wet form of macular degeneration leads to more serious vision loss. Wet macular degeneration is the result of abnormal blood vessel growth behind the retina that leak and kill the cells of the retina. Some drug and laser treatments has been developed that can slow the progression of the disease. It is not know what causes AMD although it appears with age, tends to run in families, and is more common in whites and females. You eye doctor will examine your field of vision to determine if you have early signs of the disease.
Another method is to view an Amsler grid which is a grid of parallel lines. If the lines appear wavy then you should see you eye doctor to have your eyes checked for early signs of AMD. Some studies have shown that taking vitamins A (beta-carotene), C, and E and nutrients such as zinc and lutein help lower the risk of the disease or decrease its progression. Consumption of Omega-3 fatty acids found in fish may also reduce the risk while consumption of Omega 6 fatty acids (vegetable oils) may increase your risk. There is currently no known cures for the disease.
To help prevent this disease, the American Optometric Association recommends eating at a low-fat balanced diet, keeping blood pressure under control, avoid smoking, wearing 100% UV protection sunglasses and having an annual eye exam. The best defense against Macular Degeneration or any other loss of sight is an annual eye health evaluation including a diagnostic exam of the back of your eyes through dilated pupils. Contact us to schedule your eye exam or to find out more about Macular Degeneration. We care about the health of your eyes!
Can adult amblyopia be corrected?
Generally after the age of 11 years, the brain has been trained to ignore the blurry signals received from the weaker eye. Correction of amblyopia after this age is difficult to impossible.
What is color blindness and can it be corrected?
Color blindness is a deficiency in the ability to discern certain colors. The more common deficiency is red/green and a less common is blue yellow. Color blindness is usually an inherited condition linked to the X chromosome and as such is more common in males. Color blind fathers can only pass the gene onto their daughters who may or may not be color blind depending on whether their mother is a carrier of the recessive gene. Color blindness can not be corrected. It is important to have young children tested for color blindness as it can hamper learning as much of the education material is dependent on colors. If you have color blindness you can tag items so that you know the difference or you can look for physical characteristics such as the layout of traffic lights to determine what is red and what is green. Testing is done with Ishihara plates to determine the type and severity of the colorblindness. If you can not see the numerals in the image below you are red/green color deficiency.
What is turned eye (strabismus)? Does it require surgery to correct?
Strabismus or crossed eye is caused by improper functioning of one or more eye muscles. Generally the eyes work in conjunction with one another focusing on the same spot. The brain, although it receives two images, blends these into one. This gives us our depth perception. Movement of the eye is controlled by six muscles. If these muscles do not work in concert then that eye will not focus on the correct spot. When this happens in children the brain soon learns to ignore the image from the weak eye. If not detected early in young children this situation can lead to amblyopia. In adults, a newly acquired strabismus results in double vision. Strabismus can be caused by trauma, inherited, or as the result of eye surgery. Correction for strabismus ranges from patching the stronger eye forcing the weaker eye to be used to corrective surgery. Sometimes the condition can be corrected with lenses.
What is dry eye condition?
Your eyes are covered with a tear film that has a very complex structure. It is a multi-layered fluid composed of mucus, proteins, water, and lipids. The mucus layer provides the scaffold which helps hold the moisture portion of tears to the eye. The lipid layer prevents evaporation of the water keeping the eyes moist longer. Dry eyes can be caused by environment factors such as hot, dry winds, high altitude, or dry air such as occurs in wintertime. The older we get the more likely it is that we will experience dry eyes mainly because our bodies produce less oils as we age. The reduction in oil production affects the amount of lipids in the tears which increases the evaporation of the moisture from the eye. Also work with computers or extensive reading can cause dry eye conditions as one tends to blink less frequently that normal extending the length of time between replenishment of the tear layer over the eye. This condition can be exacerbated by the wearing of contact lenses as they tend to accumulate proteins and absorb the tear layer.
Treatment for a dry eye condition can be as simple as using a high quality artificial tears product on an as needed basis. Preservative free artificial tears are probably best as they contain fewer ingredients that could potentially cause allergic irritation of the eye. Heavy daily use of artificial tears that doesn't relieve the itching and burning often associated with dry eyes is indicative of an abnormal condition that should be diagnosed by your eye doctor. Other treatments include plugging the tear ducts temporarily or permanently or the use of ointments at night. If you complain of dry eyes, your eye doctor may use a series of dyes and physical examinations to determine the cause before making a treatment recommendation.
What is Dry Eye Syndrome?
Chronic dry eye is a serious and sometimes debilitating condition that affects millions of Americans. The condition is diagnosed when any part of the tears are not functioning properly. Tears are a necessary to enable the eye to see clearly, to protect the eye from allergens or foreign pathogens and to lubricate the eye especially in dry environments. Dry eye is more prevalent in women than men and usually affects people over the age of 50.
The cause of dry eye is not always easily diagnosed. When the condition is seen in people they usually are not producing enough tears or the tears they are producing are evaporating off of the eye too quickly. The most common symptoms are burning, scratchy and irritated eyes. In severe cases the vision can be decreased or the eyes may become red. If left untreated the eye can develop a serious infection.
The tear film consists of three layers:
Lipid is the outermost layer, produced from the meibomian glands in the upper and lower eyelids. The role of this layer is to prevent the tears from evaporating. In patients who have blepharitis or acne rosacea these glands can malfunction. When this happens the people are producing enough tears but they are evaporating from the eye. The treatment may consist of warm compresses to get the oil to flow again, supplemental lubricants,Omega 3 (fish oil), flaxseed oil and/or doxycycline.
Aqueous is the middle layer and is the watery part of the tear. Aqueous is produced from the lacrimal gland. It is thought that an inflammatory process causes the lacrimal gland to malfunction and not produce enough tears. Some patients suffering from autoimmune diseases can have a decrease in the quantity of tears. The treatment consists of supplemental lubricants and in some cases punctual plugs. Punctal plugs are silicone plugs that are inserted into the upper or lower tear ducts. This keeps the tears that are produced from draining too quickly. Most recently a drug came to the market called Restasis. This drug acts directly on the lacrimal gland to reduce the inflammation and thereby allow the lacrimal gland to function properly.
Mucin is the innermost layer. It is produced by goblet cells of the conjunctiva. The main purpose of this layer is to provide a smooth surface for the aqueous layer to adhere to and to trap foreign materials before they can damage the ocular surface. This layer can be temporarily affected after Lasik surgery. The main treatment is supplemental lubricants and/ or punctual plugs.
Environmental conditions can exacerbate dry eye syndrome. People who suffer from this condition should avoid hair dryers, low humidity rooms, wind smoke and air conditioners or heaters that blow directly into the face.
Nutrition also plays a role especially in meibomian gland dysfunction. People who eat an abundance of saturated fats can suffer from this cause of dry eye. Supplements are available to increase the Omega 3's and increase the productivity of the meibomian glands.
If you or someone you know suffers from this condition there is treatment available. Our doctors and staff are available to answer your questions or schedule an appointment to have an evaluation.
Is glaucoma a hereditary disease?
Glaucoma, like so many diseases, tends to run in families. However, at least 15 specific genes have been implicated in glaucoma with different families having different gene expressions. The older you get the higher your risk factor for developing chronic glaucoma. If you are African American your risk is higher and starts at a younger age (around 45) than whites (around 60). You are at increased risk of developing chronic if you are diabetic. As glaucoma is a silent blinder because there are no symptoms until you experience vision loss, you should have a regular eye exam that includes a glaucoma test once a year. Contact us to schedule an appointment, or call during office hours if you haven't had your eyes examined in over a year.
What is retinal detachment and what causes it?
A retinal detachment if not treated promptly can lead to permanent loss of vision. It must be reattached as soon as possible. Retinal detachment can be caused by physical trauma such as might occur in a sports related eye injury or traffic accident. It can also occur spontaneously without physical injury if you are extremely nearsighted or have diabetes or sickle cell anemia. Surgery and tumors may also cause retinal detachment.. If you notice floaters, spots, greyness, flashes of light, or the lowering of a curtain or shadow over your vision you may be experiencing retinal detachment. There is no pain with the detachment of the retina. Seek help immediately from you eye doctor to prevent permanent loss of vision.
Re-attachment can be done a number of ways usually through laser surgery where the retina is "spot welded" back to its supporting structure or through cryotherapy (freezing). This is actually accomplished by sealing off leaking blood vessels or destroying new vessels (such as with diabetes). "Pinning" the retina back to its support structure can be done by injecting a bubble of gas into the vitreous humor which expands to pin the retina to the back of the eye, or the injection of silicone oil. During an eye examination, the doctor may notice small tears or holes in your retina. He or she may not recommend immediate treatment but they will monitor it closely. If you have this condition you need to schedule and keep regular eye examination appointments to prevent a possible loss of vision should the condition worsen.
What is glaucoma and can it cause blindness if left untreated?
Glaucoma is a condition where the intraocular pressure (IOP) of the eye is too high leading to damage of the optic nerve with a loss of peripheral vision. As the disease progresses and the optic nerve dies, tunnel vision results. Like your blood system, your eye have a pressure known as intraocular pressure. High intraocular pressure is caused by the inability of the aqueous humor, the fluid filling the eye, to drain properly through the eye's angle. The area in the anterior (front) portion of the eye where the cornea and the iris join is know as the angle and comprises the eye's drainage system. Hence various form of glaucoma include the term angle in them. The various types of glaucoma include, open angle (the most common), acute angle closure, narrow angle, normal tension, congenital, pigmentary, and secondary.
If left untreated, glaucoma will eventually lead to blindness. Testing for high IOP is simple and painless and usually includes an air puff test or the use of a manual tonometer with an orange dye and a blue light. Field of vision testing determines whether there has been any damage to the optic nerve. Further tests can then be run to determine the exact cause and extent of the disease. Treatment can range from special eye drops to help with drainage of the aqueous humor to eye surgery.
See "Is glaucoma an hereditary disease" for risk factors and causes. If you have not had an eye examination for over a year and you are over 60, you need to schedule an appointment to have your eyes tested for high IOP. Contact us or call our office for an appointment.
What is presbyopia?
Presbyopia is a condition which usually occurs in middle age (40+) which is due to the stiffening of the eye's lens which results in the inability to focus close in. This make close-range work increasingly difficult, usually necessitating the use of reading glasses. This ability of the eye to focus far away and up close is called accommodation..
What causes the need for bifocals with age?
Essentially, presbyopia is the reason for bifocals. The age related presbyopia (the presby- root means "old") is most likely due to the hardening of the eye's lens which makes it difficult to focus on near objects. A child's eyes can adjust as much as 10 diopters (called accommodation) but by the age of fifty you have only about 2 diopters of accommodation. All this means is a magnification prescription for "near vision" needs to be added to your regular prescription resulting in two refraction adjustments combined into a single physical lens. Bifocals and their related brethren "progressives" are available in contact or eyeglass forms.
What is astigmatism?
The cornea normally is spherical like a basketball but with astigmatism the cornea is oval taking on the shape move like a football. This oval shape result in the cornea having a steeper and a flatter curve. This result in having multiple focal points within the eye causing blurred vision both near and at a distance.
What can I do for dry eyes?
Many people suffer from dry eyes for one reason or another. The dryness can be caused from environmental conditions such as dry air and contact lenses or health conditions such as Sjogrens Syndrome. The treatment varies from person to person, however their have been some recent advancements that may help you or someone you know.
First and foremost consider the changes you can make that may make a big difference. As the weather grows colder, we do not drink as much water as we do when the weather is hot. It is important for our bodies to consume enough water to keep our, eyes, skin and other organs healthy. The air is also not as humid as in the warmer months. Consider a humidifier in your living or working areas to protect against dryness. If you wear contact lenses make sure you use a contact lens solution with moisture supplements and keep lubricating drops on hand.
For mild cases of dry eye, an over the counter lubricant may be used up to six times per day. For more severe cases, there are gels and ointments to help the eyes stay moist.
Some cases of dryness are caused by an insufficient tear secretion. Punctal plugs can be used to keep the tears that are produced inside the eye, instead of being washed away to quickly.
Many cases of dryness are caused by an inflammatory process that causes the eye to over produce watery tears instead of healthy tears. This can sometimes lead to tearing, redness and burning. Prescription drops may be helpful.
If you or someone you know suffers from dry eye make an appointment for a complete analysis and evaluation. And as always if you have any questions please let us know!
Can Erectile Dysfunction (ED) medications cause blindness?
The use of Viagra (sildenafil) has been reported (Journal of Neuro-Ophthalmology. 25(1):9-13, March 2005) as causing blindness in men within 36 hours of initial use. One report indicated that an eye examination can detect an individual at risk.
The report indicated that 34 new cases emerged with one person suffering vision loss in both eyes. The average ages ranged from 50 to 69. Some of the men had pre-existing conditions such as high blood pressure, cholesterol or diabetes. There is no specific treatment for this condition. The medication was stopped and final visual acuity ranged from 20/20 to light perception. All of the patients examined had a small optic nerve with a small cup to disc ratio. The cup to disc ratio is a standard measurement used by eye care professionals to analyze the optic nerve.
The side effect of this medication is thought to cause a condition known as non-arteritic anterior ischemic optic neuropathy (NAION). Basically, NAION is a malfunction of the optic nerve. The optic nerve carries the light (images) from the retina to the brain. When this process is interrupted, the eye can become blind. An eye examination can determine if an individual is at risk for developing blindness while taking Viagra.
The researchers say that Viagra acts like a vasoconstrictor, which may cut blood flow to the optic nerve.
A dilated eye examination can detect those individuals at risk. If you have any concerns, please contact our office or your medical doctor.