Age-related macular degeneration is an eye disease that affects central vision. It is caused by the deterioration of the macula, the central part of the retina that is essential for sharp, central vision. It is here that visual information is collected and then sent on to the brain for processing. Many people with vision loss have blank spots, or scotomas, on their retinas. With macular degeneration, the scotomas are near the macula, creating the frustrating loss of central vision that characterizes the disease.
Macular degeneration affects 1.8 million Americans, and is expected to increase to 2.9 million cases by the year 2020. Age is the biggest predictor of macular degeneration, with nearly one-third of all individuals over the age of 75 having it. In Kansas, nearly 20,000 people have been diagnosed with age-related macular degeneration.
Macular degeneration cannot be reversed, but the effects of wet macular degeneration can be slowed by certain supplements and treatments. The best solution is referral to a low vision specialist for follow-up and low vision rehabilitation to train the patient on how to use the most of their remaining functional vision.
♦ Dry AMD
Dry macular degeneration accounts for 90 percent of all cases of AMD. It occurs when small deposits of drusen, a yellowish material, accumulate on the macula. The accumulation interferes with the macula's ability to sense light, which leads to distortion and loss of central vision. This accumulation may begin as many as ten years before you notice any vision loss, and its progression is subtle and painless.
♦Wet AMD
Wet macular degeneration is caused when tiny, abnormal blood vessels begin to grow behind the retina near the macula. These vessels can leak and damage the macula, leading to rapid and sometimes severe vision loss. Wet macular degeneration almost always occurs in people who already have dry macular degeneration.
Diabetic Retinopathy
Diabetic retinopathy is an eye disease that is a result of diabetes. Diabetic retinopathy is the leading cause of blindness in the U.S., causing up to 24,000 new cases every year. In Kansas, more than 50,000 people have diabetic retinopathy.
Diabetic retinopathy causes small blood vessels that line your retina to weaken, eventually rupturing, blurring your vision and causing swelling. If diabetic retinopathy is untreated, about half of all cases will result in blindness.
The severity of diabetic retinopathy can be minimized significantly with proper diagnosis and care. Careful diabetes care, managing a healthy lifestyle, smoking cessation, and appropriate management by an ophthalmologist and retina specialist can stabilize disease and reduce vision loss. For the two most common complications, macular edema and proliferative retinopathy, laser and local drug therapy can improve short and long-term outcome. Laser treatment for proliferative retinopathy can prevent blindness, though peripheral vision may be reduced. Pharmacological therapy directly to the eye may also be used to stabilize diabetic retinopathy.
Glaucoma
Glaucoma is a family of eye diseases that tend to cause vision loss through damage to the optic nerve, often caused by increased pressure in the eye. This pressure kills nerve cells in the optic nerve, the cable that sends information from the eye to the brain. Untreated, glaucoma can cause total blindness.
While there is no cure for glaucoma, the disease can generally be managed through medication or surgery. The goal of these treatments is to control the pressure in the eye, by either reducing the amount of fluid that comes in, or by “unclogging” the drain.
In the U.S. about three million people are estimated to have glaucoma. Half are unaware that they have the disease. As our population ages, the number of people with glaucoma is expected to rise. Another ten million Americans have high intraocular pressure and are at risk for glaucoma. More than 20,000 Kansans have been diagnosed with glaucoma.
Retinitis Pigmentosa
Retinitis pigmentosa, or RP, is the name of a group of inherited eye diseases that cause degeneration of the retina and progressive vision loss. It is most commonly diagnosed in children, with severe vision loss usually developing in young adulthood.
With retinitis pigmentosa, the nerve cells degenerate and die, and patients experience gradual vision loss. Usually it is the rods that stop working, and vision loss is manifested by loss of peripheral and night vision because these cells help us see in the dark and to the sides. In some cases, when the cones degenerate, central vision is affected because these cells are concentrated in the center of the retina. The hallmark of the disease is dark, bone spicule pigmentation spots in the retina.
Retinitis pigmentosa is a rare disorder, affecting about 1 in 4,000 people in the United States, or about 100,000 total. It commonly runs in families, and is caused by defects in a number of different genes that have recently been identified. Some forms of retinitis pigmentosa can be associated with deafness, kidney disease and other malfunctions, central nervous system and metabolic disorders, and chromosomal abnormalities.
Retinitis pigmentosa has no cure, either from surgery or treatments by medicine.
Vision Loss from Stroke and Traumatic Brain Injury (TBI)
A stroke occurs when there is a disruption of blood flow in the brain. The effects of stroke depend on the part of the brain that is affected, and can include impaired body movement, speech or sensory function.
After speech impairment, the two most common effects of stroke affect your ability to see. Hemianopia is present in about 15 percent of stroke patients. This condition blanks one side or one quadrant of your vision in each eye. This creates difficulty for the patient to complete even simple tasks, such as walking straight ahead, reading all the way across a page, or seeing all the food on a plate.
Diplopia, or double vision, affects about six percent of all stroke patients. In this condition, the two eyes fail to work together properly. In addition to losing depth perception, patients with diplopia face a reduced field of vision and everyday visual confusion.
Traumatic brain injury (TBI) yields similar results to vision as stroke. There are approximately 8 million head injuries reported each year. Of those, 1.5 million are deemed serious. With TBI, a patient may experience loss of visual field, visual neglect, vertigo, dizziness, impaired eye movements, double vision, eyestrain and difficulty reading, sensitivity to light, dry eyes, visual hallucinations and impaired visual memory.
For parents with visually impaired children, it can be challenging to find the right services and programs. Consider the information below outlining important information regarding pediatric vision loss. Excellent guidance is available to parents through Families Together, which provides an information center serving Kansas families with children who have disabilities.
The Kansas Association for Parents of Visually Impaired Children (KAPVI) is an organization designed to assist families of children with visual impairments. KAPVI is the Kansas state chapter of NAPVI, the National Association for Parents of Children with Visual Impairments.
Additional support can be found through Envision, a Wichita-based non-profit organization whose goal is to provide independence for people who are blind or low vision. Two support groups exist for children with visual impairments: Route 4-12 and Laughing Out Loud.
Additional information can be found through Family Connect.
A Viewpoint of Pediatric Care (PDF)
What Parents Should Know and Do:
1. Do not second-guess yourself. If you feel your child has a visual impairment, see a doctor. During the age of birth through seven years, time is critical.
2. Ask other parents, visually impaired teachers and friends who you should see to evaluate your child.
3. Look for a doctor that gives you face to face time, appears interested, communicates to your satisfaction and has you feeling resolved with the evaluation, communication, care and long term plan. If they don’t, change doctors, immediately. They are not your higher being.
4. Align yourself with your children’s teachers, other parents with visually impaired children and all individuals that teach your child that all things are possible.
5. Remember that the first years of life are critical for good vision and an all-out effort for intervention is extremely important to your child’s “rest of their life.”
6. Just as you would expect in the emergency room, collectively, a team is likely to provide better care than a single person - even a doctor.
Cortical Vision Impairment
Rather than a condition of the eye, cortical vision impairment (CVI) is a condition of the brain. With this condition, the eyes and the optic nerve may be completely healthy, yet the brain doesn’t process the information correctly.
CVI can be caused by insufficient oxygen supply to the brain, incomplete brain development, head trauma and other neurological disorders. It can be detected in infants and children by the child’s seemingly changing level of vision (which can fluctuate from day to day), poor attention to visual stimuli, or delayed response to visual stimuli. Vision levels may improve in children, but improved visual processing is difficult to predict.
Retinopathy of Prematurity
Retinopathy of prematurity (ROP) is a potentially blinding eye disorder that primarily affects premature infants weighing less than three pounds that are born before 31 weeks of gestation. The smaller a baby is at birth, the more likely that baby is to develop ROP. ROP, which usually develops in both eyes, is one of the most common causes of vision loss in childhood and can lead to lifelong vision impairment and blindness.
Due to medical advancements, more and more premature babies are able to survive. Because of this, the incidences of ROP have increased. Approximately 14,000 infants are born each year with ROP. About 500 of these cases result in blindness.
ROP occurs when abnormal blood vessels grow and spread throughout the retina. These abnormal blood vessels are fragile and can leak, scarring the retina and pulling it out of position. This causes retinal detachment. Retinal detachment is the main cause of visual impairment and blindness in ROP.
There are several treatments available for different stages of ROP, including laser therapy, cryotherapy, scleral buckle and vitrectomy. Though these treatments may decrease the chances of vision loss associated with ROP, they do not always prevent it. You can find more information from The Association for Retinopathy of Prematurity and Related Diseases (ROPARD) website.
Stargardt’s
Stargardt’s disease is much like macular degeneration, though it primarily affects children and young adults. The condition is a group of inherited diseases that cause light-sensitive cells in the retina to deteriorate, causing loss of central vision.
Stargardt’s is passed down to a child when both parents carry the gene mutation that causes the disease. These genes may be recessive and the parents themselves may not have the disease or know they are a carrier.
Symptoms of Stargardt's can include blurry or distorted vision, inability to see in low lighting and difficulty recognizing familiar faces. In late stages of Stargardt's, color vision may also be lost. Vision loss from the disorder usually appears in the first 20 years of life, though some people with Stargardt’s may reach middle age before symptoms are noticeable.
There is no known cure or treatment for Stargardt’s, though the disease does appear to be amplified by exposure to bright light, so UV protection through the use of sunglasses is strongly encouraged.
Low Vision Rehabilitation Services and Intervention
Ophthalmologists, optometrists, family, educators and therapists are all part of the low vision rehabilitation team. This may include community health nurses, school nurses, social workers and case managers, occupational therapists, teachers of the visually impaired (TVIs), early childhood special education teachers and orientation and mobility specialists. Kansas children and youth with visual impairments should have access to high quality eye exams by an optometrist or ophthalmologist specializing in low vision.
Kansas Statewide Low Vision Clinics
Due to the generosity of the Kansas Lions Sight Foundation, Dr. William Park participates in the Kansas Low Vision Statewide Project (KSLVP). KSLVP may be able to provide assistance in obtaining a low vision exam. Please call for availability.
Unified School District 259
Dr. William Park has a contract to provide low vision examination for children in USD 259. Please call for details.