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04/06/2009 - Articles Vision Problems in Parkinson's Disease By: Robert W. Griffith, MD Eye problems are not uncommon in people suffering from Parkinson's disease. In such cases it's important to recognize that Parkinson's may be responsible, in order to prevent unnecessary surgery and obtain the most appropriate treatment. Eye problems are not unusual in people with Parkinson's disease. Dr Jay B Lavine is an ophthalmologist from Tucson, Arizona, USA, who has written a most helpful article in the latest Educational Supplement published by the American Parkinson Disease Association. We reproduce it in full here. Robert Griffith, Content Editor, HealthandAge.com. Vision Problems and Parkinson's Diseaseby Jay B Lavine, MD Symptoms Stiffness and tremor are the hallmarks of Parkinson's disease (PD), but eye problems can also interfere with quality of life as well. People with Parkinson's usually develop a stare because they don't blink as frequently as they used to and involuntary closing of the eyelids is also a frequent occurrence. Eye movement disorders are apparent on examination, although they do not always cause problems from a functional standpoint. For example, the eyes may not move much in an upward direction, something that occurs to a lesser degree in many people as they age, but this may not bother most people. The eyes may have difficulty fixating on objects and following them as they move. Occasionally, because of a lack of eye coordination, people experience double vision, which may be present only when looking in certain directions. Most commonly, this occurs at the reading distance and is called convergence insufficiency. Some people who have this problem do not complain of double vision, but say that their eyes tire quickly when they read or that the words start to run together. These problems are all caused by the degeneration in the brainstem of people with PD. This degeneration results in low levels of dopamine, an important chemical messenger in the brain. The degenerative changes may cause other problems as well. Special tests measuring electrical activity in the eye and in the brain, such as the visual evoked potential (VEP) and the electro-retinogram (ERG) have shown abnormalities in people with Parkinson's. Symptoms caused by these abnormalities include reduced vision, poorer color vision, and difficulty appreciating the correct location or orientation of an object. It is not clear whether all of these vision problems are the result of the degeneration in the brain or whether some may be due to lowered dopamine levels in certain cells of the retina (lining of the back wall of the eye that transmits images to the brain via the optic nerve). Although not all vision problems may be treatable, it is important that their cause be recognized so that unnecessary surgical procedures, such as cataract surgery, are not performed. Many people, especially those with more advanced Parkinson's disease, suffer from visual hallucinations. They may sometimes see people, animals, or objects that aren't really there. The hallucinations may be in color or in black and white, and they may be moving or still. They can cause frustration and can be very debilitating for some people. Again, degenerative changes in the brain play a role, although the drugs used to treat PD can, in themselves, contribute to the problem. The lack of blinking often causes problems, especially with reading. Blinking is necessary to keep the front surface of the eye moist and to preserve the quality of the tear film that coats the cornea (front surface of the eye). With inadequate blinking, the tears bead up on the cornea with dry spots in between these watery islands, much as you might see on a newly waxed car. This can cause discomfort and interfere with vision. Furthermore, without the windshield wiper-like motion of the eyelids, the quality of the tear film suffers greatly. Oily debris builds up within the tear film, creating a ""dirty" tear film. This destabilizes the tear film and allows the dry spots to appear on the eye even sooner than they would otherwise. As a result of these problems, along with the dryness of the eyes that often accompanies aging, people with PD may have difficulty reading and seeing clearly in general. A competent ophthalmologist can measure both the quantity and the quality of the tears. Again, it is important to recognize the cause of these problems so that unnecessary surgery is not done. Treatment Preservative-free artificial tear eye drops, sold over the counter, can be used as a way of lubricating the eye and temporarily improving the quality of the tear film. However, because of the involuntary spasmodic closing of the eyelids that is often present, it may not always be easy to instill the drops. And the effect of the drops may be for no more than fifteen minutes. It's fine to use the drops that frequently, provided they are the preservative-free kind. These drops lack the chemicals that can irritate the eye when drops are used more than two or three times a day. They are packaged in single-use containers, usually about thirty to the box. Different brands use different formulations, and no onebrand can be recommended for everyone. Everyone's tears are different in terms of their acidity, viscosity, salt content, etc. Try different ones and see which one works best for you. Using an eye-wash to flush out the debris and wet the eye may also be helpful. Double vision problems may be difficult to treat. Eye muscle exercises are not usually helpful. Prisms, which are special lenses that help keep the eyes in alignment, are worth trying. They can be part of an eyeglass prescription, but temporary paste-on prisms called Fresnel lenses can be used on a trial basis. If that doesn't work, there is one surefire remedy that never fails to eliminate the double vision: occlusion (covering up) of either eye. Don't dismiss this alternative out of hand. There is no law that says you have to use both eyes together all the time! There are ways of occluding an eye that are barely noticeable to other people. Translucent patching materials and even clear nail polish applied directly to an eyeglass lens can do the trick. Sometimes just part of one lens needs to be occluded, allowing unobstructed vision throughout the balance of the lens. If you have hallucinations, report them to your medical doctor. Sometimes adjustment of your medication dosage can lessen the problem. If they are becoming debilitating, medication that can suppress the hallucinations without worsening other Parkinson's symptoms can be prescribed. Two of the more promising drugs are clozapine and quetiapine. Like most medications, they can have side effects. For example, clozapine may rarely cause the bone marrow to stop making certain white blood cells, and quetiapine can occasionally cause dizziness or rarely fainting because of low blood pressure. Therefore, the patient must be closely monitored by the attending physician. The ultimate solution to the eye and vision problems seen in Parkinson's disease will be better treatment of the underlying disease or even prevention. Better drugs are being developed and a dietary approach can be valuable as well. Many patients with Parkinson's disease develop the on-off syndrome, in which the symptoms of the disease come and go. Higher protein diets seem to contribute to the problem, inhibiting the absorption of L-dopa-containing medication such as Sinemet® and interfering with its ability to enter the brain. A fiber-rich, plant-based diet, containing large amounts of vegetables, fruits, whole grains, and nuts, is lower in protein than the overly rich average American diet and can help alleviate this problem. At the same time, it can lessen constipation and promote heart and bone health. Conclusion Some of the vision problems occurring in people with Parkinson's disease may seem daunting to some, but don't let them overwhelm you. Never give up! Educate yourself about what can be done, including what you can do for yourself. This is especially important in today's health care environment. Instead of focusing on your limitations, focus on what you can still do and make the most of it! Source Lavine JB. Vision problems and Parkinson's disease. American Parkinson Disease Association, Inc. 1250 Hyland Blvd. Ste 4B, Staten Island, NY 10305. Educational Supplement #17, 2002. The American Parkinson's Disease Association Parkinson's Disease - Dealing With 'Wearing-Off' Rayilyn Brown Director AZNPF Arizona Chapter National Parkinson Foundation [log in to unmask] ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn