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Do wavy lines seen on the Amsler grid differentiate dry from wet macular degeneration?
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∙ 12y ago
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∙ 12y ago
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What does macular degeneration produce?
Macular degeneration is a vision problem that produces symptoms that include straight lines that appear wavy or distorted, formation of drusen, a dark spot or area at the center of your vision, and changes in color perception. Macular degeneration is a disease of the macula in the retina. A drusen is a yellow or white deposits found in a retina layer.
How To Diagnose Macular Degeneration?
you get macular degeneration from getting repeated sunburns Macular degeneration (AMD) is the result of many different processes that lead to degeneration or dying of photoreceptor cells in the macula. The macula is a tiny spot in the center of the retina. It is responsible for our straight ahead or central vision. The vision that is required to read a book or recognize a face. Peripheral vision is still functioning. When circulation to the macula is hindered, nutrients and oxygen are unable to nourish it and waste products build up causing even more harm. Genes play an important role in causing macular degeneration. Those who smoke are at a much higher risk of developing AMD because of the damage that it causes to the blood vessels. Those with high blood pressure are also at greater risk, because of the silent damage from hypertension to the artery walls. The aging process from oxidation leads to degenerative diseases like AMD as does chronic inflammation.
What You Should Know About Macular Degeneration?
For many people, macular degeneration is a natural consequence of aging. Macular degeneration refers to the gradual decline in vision quality, specifically, in the center of the field of vision (called the macula), and occurs as a result of damage to the retina. About 10 percent of people aged 66 to 74 experience macular degeneration, and for people over 75 years old, this proportion increases to over 30 percent. Macular degeneration can come in one of two forms: "wet" and "dry." Each type is characterized by a different form of damage leading to the loss of vision.Dry macular degeneration is caused by damage to the cells beneath the retina, which can kill the rod and cone cells that receive visual information. Unfortunately, no treatment seems to be effective in preventing the death of these cells. However, certain antioxidants can help slow down this process, and in some cases, even slightly improve vision.Wet macular degeneration is caused by the swelling of certain blood vessels, which creates a leakage of blood and proteins into the macular area. The bleeding and scarring process damages the rod and cone cells, and, if left untreated, can cause rapid damage to vision, unlike the slow progress of dry macular degeneration. This form of the disease can be treated by the direct injection of drugs called anti-angiogenics into the eye. These drugs prevent the growth of blood vessels, so they allow the swollen vessels to retract, and the eye to heal. However, only about 10 percent of all macular degeneration cases are wet, so a cure for most cases has yet to be foundWhile macular degeneration does not cause complete blindness, there are some symptoms that it is generally associated with. These can include: blurred vision, a decrease in visual acuity, seeing shadows or blind spots in part of the visual field, an increase in peripheral vision (in the wet form), and distorted vision, specifically with regards to seeing straight lines as wavy. Since only about 2 percent of the visual field consists of the macula, most vision is still retained, but the macula is important to sight (for example, it's essential for reading) so consulting an ophthalmologist is crucial if visual changes are noted.
What is the purpose of an Amsler grid?
With a Amsler grid one can determine if one has distortion in ones visual field. Distortion means that objects alter shape. A Amsler grid is a square which is devided into many smaller squares and a dot in the middle. From the dot there are lines going out to the corners of the big square.
What can macular degeneration cause?
MaculardegenerationDry maculardegeneration is a chronic eye disease that causes vision loss in the center of your field of vision. Dry maculardegeneration is marked by deterioration of the macula (MAK-u-luh), which is in the center of the retina - the layer of tissue on the inside back wall of your eyeball. Dry maculardegeneration is one of two types of age-related maculardegeneration. The other type - wet maculardegeneration - is characterized by swelling caused by leaky blood vessels in the back of the eye. Dry macular degeneration isn't associated with swelling and is the more-common form of the disease.Dry macular degeneration doesn't cause total blindness, but it worsens your quality of life by blurring or causing a blind spot in your central vision. Clear central vision is necessary for reading, driving and recognizing faces.SymptomsDry macular degeneration symptoms usually develop gradually. You may notice these vision changes:The need for increasingly bright light when reading or doing close workIncreasing difficulty adapting to low light levels, such as when entering a dimly lit restaurantIncreasing blurriness of printed wordsA decrease in the intensity or brightness of colorsDifficulty recognizing facesA gradual increase in the haziness of your overall visionA blurred or blind spot in the center of your field of visionHallucinations of geometric shapes or people, in cases of advanced macular degenerationDry maculardegeneration may affect one eye or both eyes. If only one eye is affected, you may not notice any or much change in your vision because your good eye compensates for the weak one.When to see a doctorSee your eye doctor if:You notice changes in your central visionYour ability to see colors and fine detail becomes impairedThese changes may be the first indication of maculardegeneration, particularly if you are older than 50.
Macular degeneration?
DefinitionMacular degeneration is an eye disorder that damages the center of the retina, which is called the macula. This makes it difficult to see fine details.Alternative NamesAge-related macular degeneration (ARMD); AMD; senile macular degeneration (SMD) is an older name that is no longer in common use.Causes, incidence, and risk factorsThe retina is the layer of tissue at the back of the inner eye. It changes light and images that enter the eye into nerve signals that are sent to the brain. The macula is the part of the retina that makes our vision sharper and more detailed.Macular degeneration is caused by damage to the area around blood vessels that supply the macula. This change in the blood vessels damages the macula.Two phases of macular degeneration (AMD) exist:Dry macular degeneration occurs when the blood vessels under the macula become thin and brittle. Small yellow deposits, called drusen, form under the macula. As these drusen increase in size and number, they create a blurred and dim spot in the central vision of the eye. Almost all people with macular degeneration start with the dry form.Wet macular degeneration occurs in only about 10% of people with macular degeneration. Brittle vessels break down and new abnormal and very fragile blood vessels grow under the macula. This is called choroidal neovascularization. These vessels leak blood and fluid, which leads to damage of the macula. Although only about 10 percent of people with macular degeneration have this form, it causes most of the vision loss associated with the condition.Scientists aren't sure what causes AMD. The disease is most common in people over 60, which is why it is often referred to as age-related macular degeneration.In addition to heredity, other risk factors are:Caucasian raceCigarette smokingHigh-fat dietFemale genderObesitySymptomsAt first you may not have symptoms. As the disease progresses, your central vision may be affected.The most common symptom in dry AMD is blurred vision. This is limited to the center of the field of vision. Often objects in the central vision look distorted and dim, and colors look faded. A patient may have trouble reading print or seeing other details, but can generally see well enough to walk and perform most routine activities.As the disease becomes worse, you may need more light to read or perform everyday tasks. The blurred spot in the center of vision gradually gets larger and darker. In the later stages, you may not be able to recognize faces until people are close to you.AMD typically does not affect side (peripheral) vision. This is very important, because it means you will never have complete vision loss from this disease.The most common early symptom of wet macular degeneration is that straight lines appear distorted and wavy. You may also notice a small dark spot in the center of your vision that gradually gets larger. Central vision loss can occur very quickly. If this occurs, you urgently need evaluation by an ophthalmologist with experience in retina disease.Signs and testsIf you are over age 60 and you've had changes in vision, your eye care provider will do an examination. During the exam, the doctor will use drops to enlarge (dilate) your pupils, and a special lens to view your retina and optic nerve.The doctor will look for changes in the blood vessels and the membrane that surrounds them. This may show drusen, the yellow deposits that form on this membrane in dry macular degeneration.You may be asked to cover one eye and look at a pattern of lines called an Amsler grid. If the straight lines appear wavy, it may be a sign of AMD.Other tests for macular degeneration may include:Fluorescein angiogramOptical Coherence Tomography (OCT)TreatmentNo treatment exists for dry macular degeneration. However, a combination of vitamins, antioxidants, and zinc may slow the progression of the disease. This combination of vitamins is often called the "AREDS" formula. Smokers should not use this treatment.The recommended supplements contain:500 milligrams of vitamin C400 international units of beta-carotene80 milligrams of zinc2 milligrams of copperAlthough there is no cure for wet AMD, treatments may include:Laser surgery (laser photocoagulation) -- a small beam of light destroys the abnormal blood vessels.Photodynamic therapy -- a light activates a drug that is injected into your body to destroy leaking blood vessels.Special medications that slow the formation of new blood vessels in the eye (anti-angiogenesis, anti-VEGF therapy) -- drugs such as bevacizumab (Avastin) and ranibizumab (Lucentis) are injected into the eye to stabilize or improve vision. This is a painless process.Low-vision aids (such as special lenses) and therapy can help you use the vision that you have more effectively, and improve your quality of life.Support GroupsAMD Alliance International -- (877) AMD-7171 -- www.amdalliance.org.Expectations (prognosis)Most people with mild dry macular degeneration will not have disabling central vision loss. However, there is no way to predict who will progress to a more severe form of the disease.The wet form of macular degeneration often leads to significant vision loss.Although macular degeneration can cause people to lose the ability to read, drive a car, and recognize faces that are not very close, it never causes complete blindness. This disorder results in the loss of central vision only -- macular degeneration cannot cause peripheral vision loss.Nearly everyone with macular degeneration can get around, eat, perform personal hygiene, and do other routine activities without too much difficulty.ComplicationsLoss of central vision may interfere with many daily activities, such as reading, working on the computer, or driving. You may need extra light or magnification to perform many of your normal activities.Calling your health care providerIf you have AMD, your health care provider may recommend that you check your vision every day on an Amsler grid. Call your provider immediately if the lines appear wavy, or you notice any other changes in your vision.PreventionAlthough there is no known way to prevent macular degeneration, lifestyle factors can reduce your risk of developing the condition:Don't smokeEat a healthy diet that is high in fruits and vegetables and low in animal fatExercise regularlyMaintain a healthy weightSee your eye care professional regularly for dilated eye exams.ReferencesAmerican Academy of Ophthalmology Preferred Practice Pattern in Macular Degeneration.The Age-Related Eye Disease Study (AREDS).Gohel PS, Mandava N, Olson JL, Durairaj VD. Age-related macular degeneration: an update on treatment. Am J Med. 2008;121(4):279-281.Martidis A, Tennant MTS. Age-related macular degeneration. In: Yanoff M, Duker JS, Augsburger JJ, et al., eds. Ophthalmology. 2nd ed. Philadelphia, Pa: Mosby Elsevier; 2004:chap 125.
What is the prognosis for a patient with macular degeneration?
The vision of patients with age related macular degeneration (AMD) is affected in several different ways depending on which type of AMD they have. The two types are dry and wet AMD. Wet causes the most severe vision loss. When the photoreceptor cells of the macula, a tiny spot in the center of the retina, start dying or degenerating people will notice that they need more light to see clearly. Images seem blurry and are less sharp and crisp. That's because the macula is responsible for our detailed vision. Colors are less vivid and the world is not as bright as it used to be. As the AMD progresses they may notice a blurry or blank spot in the center of their vision or that straight lines now appear crooked or wavy.
What are treatments for wet macular degeneration?
The macula is a tiny spot in the center of the retina. There are several layers of tissue that bring nutrients and oxygen to the macula and remove built up waste products. One layer of tissue is called the choroid layer - this is a layer of blood vessels that helps with the transporting in nutrients and removing waste. In wet macular degeneration new but abnormal blood vessels grow and instead of helping with this transport system, they actually are harmful. The reason for this is that these abnormal blood vessels are very tiny and fragile - meaning that they leak fluid.Wet macular degeneration gets it's name because of this excess blood and fluid from leaky blood vessels.This abundance of fluid builds up under the macula and raises it which is what causes the distortion of vision - straight lines become wiggly or wavy.What causes these unusual blood vessels to develop? There is a term called angiogenesis which means "new blood vessels."Vascular endothelial growth factor (VEGF) is a protein secreted by cells that are oxygen deprived. VEGF stimulates the growth of these abnormal blood vessels.Healthy adults secrete very low levels of VEGF, while those who have health conditions such as cancer or age related macular degeneration secrete high levels of this protein.
What lines heart chambers?
These cells can differentiate into endocardium which lines the heart chamber
Why do straight lines appear to bend without your glasses?
You need to see an optometrist for this. It may just be the nature of your prescription but straight lines appearing bent can (very rarely so please don't panic!) be symptom of an eye condition called Macular Degeneration. Most common in older people, this condition has the power to destroy sight if it isn't caught early enough and damaged cells will never regenerate.
What is macular degenative disease?
Macular degeneration, sometimes mistakenly (or jokingly) called 'immaculate degeneration,' is a condition that affects the macula, the central part of the retina. When the macula is damaged, the eye loses the ability to see detail clearly in the center of the field of vision. The earlier it is detected and treated, the better the chances are of limiting the damage. There are new drugs on the market that are being tested with a high degree of success, so if you suspect you or someone you know may have it, see an eye doctor as soon as possible. Good luck.
Macular Degeneration Explained?
Around the age of 60, people need to be concerned about the condition known as age-related macular degeneration. At this time, the maculae, the areas on the eye that allow for the detection of the details within objects, can begin to deteriorate. When this happens, people begin to have difficulties recognizing faces, being able to see well enough to drive and may even completely lose their sight.People have two types of macular degeneration: wet age-related macular degeneration (wet AMD) and dry age-related macular degeneration (dry AMD).Wet AMDWet AMD occurs when abnormal blood vessels behind the eye where the maculae are located begin to grow. Because these are not the sturdiest of blood vessels, they tend to leak blood and other eye fluids into the maculae. Because there is excess blood and other fluid in this area, the maculae become displaced and damage occurs.With Wet AMD, vision loss can occur very rapidly, and it can be recognized by how lines appear; lines that are actually straight will appear to be wavy.Dry AMDOne of the reasons dry AMD is different from Wet AMD it that it causes the person's vision to deteriorate in stages. Dry AMD is a condition of the maculae where they are degenerate and keep the eye from focusing adequately on objects. The first symptom will be that the affected person will see a blurred spot in the central vision. As time goes by, the central vision becomes worse, and a total loss of vision occurs.A common symptom that people notice when this condition begins is blurred vision, and it is the condition that will keep them from recognizing familiar faces. They may also notice that they will need more light to read and do other things.Who Is At Higher Risk?This condition is age-related, but there are other factors that raise a person's risk of contracting this condition. Those at higher risk are smokers, Caucasians, the obese, women and those whose immediate family members have contracted the condition. People with these extra risk factors who are also over the age of 60 are advised to make an appointment with their eye doctors for an AMD examination as soon as possible.
