Diseases of the Eye Fact Sheets Retinopathy of Prematurity Toxoplasmosis

1. Diseases of the Eye Fact Sheets • Retinopathy of Prematurity • Toxoplasmosis • Diabetic Retinopathy • Macular Degeneration • Albinism 7/16/2007 Developed by Pam Holmes

2. Retinopathy of Prematurity Retinopathy of Prematurity, ROP, also know as Retrolental Fibroplasia, is a congenital disease caused by high oxygen exposure in premature infants. Although scientists believe there are other causes, no specific findings have been proven. When an infant is born prematurely (under 32 weeks of gestation) the normal blood vessel growth stops and new abnormal vessels begin to grow. Scar tissue develops which causes damage to the retina. The damage may be mild with no visual defects, or it may progress to retinal detachment and blindness. • Functional Problems • Visual problems will vary but typically include visual acuity loss, significant field loss, strabismus, nystagmus, amblyopia, and myopia. Retinal detachment is common and cataracts and glaucoma may develop later in life. • Low Vision Care • early intervention with • sensory stimulation • high contrast materials • high illumination • bifocals, magnifiers, closed • circuit television • braille (severe loss) • Developed by Pam Holmes Treatment Cyrotherapy or freezing of the retinal tissue has been used in the past. Now, laser therapy is just as effective with fewer side effects. Scleral buckling, a procedure that places a band around the globe of the eye to bring the retina back into contact with the inner layer of the eye is used if a retinal detachment has occurred. Also, a vitrectomy is used to remove scar tissue in severe cases. • Sources: • http://www.emedicine.com/ophtopic413.htm • http://www.lowvision.org/retinopathy_of_prematurityxx.htm • Program in Low Vision Therapy, Region 4 Education Service Center, Bill McKinney, Ph.D. Executive Director, 2004. Houston, TX pg 24 • http://www.rnib.org.uk.xpedio/groups/public/documents/PublicWebsite/public_rnib003663.hcsp • http://www.tsbvi.edu/Outreach/seehear/winter98/rop.htm

3. Toxoplasmosis What is it? Toxoplasmosis is an infection caused by a parasite most often found in cats and farm animals. People contact toxoplasmosis by eating raw or undercooked meat that’s infected, eating contaminated fruits or vegetables, by coming into contact with infected feces, or an infected pregnant woman can pass it to her unborn child. Babies who become infected during their mother’s first trimester usually have the most severe problems. Congenital toxoplasmosis is the most common way that the disease is acquired and the eye is often affected. Treatment Spiramycin throughout pregnancy; Antibiotics and steroid tables during an infection; pyrimethamine/sulphadoxine for 6-12 months as follow-up. Because recurrences can be seen the treatment is to control the infection and limit the resulting scarring. The infection often invades the retina and choroid. When the inflammation settles, a scar is usually left on the retina. Symptoms are floaters and blurred vision. If the scarring is on the central macula, detailed vision will be affected. Nystagmus, amblyopia, or squint may also be present. Although the damage does not get any worse, the germ may become active again and cause additional damage if not controlled. Sources http://kidshealth.org/PageManager.jsp?dn=KidsHealth&lic=1&ps+107&cat_id=20045&art... http://www.nlm.nih.gov/medlineplus/ency/imagepages/17186.htm www.patient.co.uk/show/doc/40000376/ Program in Low Vision Therapy, Region 4 Education Service Center, Bill McKinney, Ph.D. Executive Director, 2004. Houston, Tx pg 25 www.viscotland.org.uk Developed by Pam Holmes

4. Diabetic Retinopathy What is it? Diabetes is a disease in which the body does not use and store sugar properly. It results in many health problems; diabetic retinopathy is one of them. Diabetic Retinopathy  is a disease of the small blood vessels of the retina of the eye. The mildest form is called non-proliferative retinopathy and the most severe stage is known as proliferative retinopathy. This disease is more common in patients with juvenile-onset diabetes than adult-onset. The Effects No symptoms occur in the early stages. The vision loss generally occurs after approximately 20 years of ongoing diabetes. The eye’s retina is damaged because the system of blood vessels nourishing the front surface of the retina is weakened. Abnormal blood vessels form and may leak fluid into the retina which causes swelling. This is called macular edema. Spots, or floaters, may develop causing decreased vision acuity and some degree of field loss. In the later phases of the disease, continued abnormal vessel growth and scar tissue may cause serious problems such as retinal detachment and glaucoma and can lead to blindness in severe cases. Developed by Pam Holmes 1. www.diabetes.org.au/glossary.htm 2. http://www.mayoclinic.com/health/diabetic-retinopathy/DS00447 3. http://nihseniorhealth.gov/diabeticretinopathy/toc.html 4. Program inLow Vision Therapy, Region 4 Education Service Center, Bill McKinney, Ph.D. Executive Director, 2004. Houston, Tx pgs 11- 12 5. http://www.stlukeseye.com/Conditions/DiabeticRetinopathy.asp

5. Macular Degeneration (MD) What is Macular Degeneration? Macular degeneration (MD) is the physical breakdown of the macula. Since the macula is responsible for central vision, damage to this tissue causes blurred vision or a blind spot in central vision. This progressive disease causes different levels of acuity and field loss but does not cause total blindness. Vision loss can occur over a short period of time, but usually occurs gradually, affecting both eyes at different rates. It is important for patients to have good lighting and high contrast materials, as well as magnification. • Treatment • Treatment may slow vision loss but the damage cannot be reversed. For “dry” MD, there is no treatment. Laser surgery and new antivascular endothelial growth factor medication (anti-VEGF) may control vision loss in “wet” MD. • Patients should monitor their health closely by: • following a low fat, low cholesterol diet • use UV protection in sunlight • eat two servings of dark, green, leafy vegetables daily • do not smoke • eat foods and take supplements rich in vitamins E, C, & Lutein • Types of Macular Degeneration • Juvenile or Stargardt’s – early form of MD. • Best’s Vitillform-starts out as cyst on the macula. –reduces central vision • Age Related MD- seen in the elderly population. –two common forms: wet and dry. The dry MD can turn into the wet MD. http://www.cnn.com/HEALTH/library/DS/00284.html http://www.eyesight.org/Adult/adult.html http://www.i-care.net/faq-amd.htm#WI http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/ 19532.jpg Program in Low Vision Therapy, Region 4 Education Service Center, Bill McKinney, Ph.D. Executive Director, 2004. Houston, Tx pg 18 Developed by Pam Holmes

6. Albinisim • Albinism is a congenital disease inherited from both parents. Children with albinism often have very light skin, hair, and vision impairment. This results from the body’s inability to produce normal amounts of the pigment, melanin. The lack of melanin in the development of the retina is the main cause for the visual impairment. The degree of impairment varies, but typically includes: • macular hypoplasia which results in decreased clarity of vision • nystagmus- a rhythmical involuntary flicker of the eye • photophobia- light sensitivity due to the lack of pigment in the iris • refractive errors - myopia, hyperopia, astigmatism • strabismus – an abnormal turning of the eye due to extraocular muscle imbalance Functional Problems Due to photophobia, children need tinted glasses or sunglasses in bright light and require indirect lighting inside. Depending upon the level of decreased acuity, students may need low vision aids such as magnifiers, telescopes or large print materials when reading. Glasses may be prescribed to correct refractive errors if present. . TREATMENT There is no cure for albinism. TESTING Often the VEP (Visual Evoked Potential) test is helpful in diagnosing Albinism. Another test commonly used is transillumination which determines how much light “leaks” through the iris. In a darkened room, a penlight is placed against the side ot the eye. Light coming from behind the iris shines out. In persons with albinism, more light shines out because the iris has little pigment, and is translucent. • To enable children to see printed materials better, use the following: • high contrast uncluttered backgrounds • well-defined pictures • large print text • primary colors • Developed by Pam Holmes • Sources: • http://albinism.med.umn.edu/newfacts.htm • http://www.albinism.org/publications/lowvisionaids.pdf • http://www.blindbabies.org/fact_sheet_albinism.htm • http://www.e-advisor.us/medassessments/albinism.html • www.viscotland.org.uk