Albinism: Low Vision Considerations
Richard L. Windsor, O.D., F.A.A.O.
Laura K. Windsor, O.D., F.A.A.O.
Published in Vision Enhancement Magazine
Albinism is a set of inherited disorders that result from the inability of the body to produce melanin pigment. Melanin is dark pigment that protects our tissues from ultraviolet radiation. The process of forming melanin in the body takes many steps and may be affected by genes on six different chromosomes. Due to the many genetic variations causing this condition many different forms of albinism may occur. The most severe form of albinism presents with little or no pigmentation of the skin, hair and eyes. These individuals present with white/platinum hair, pink skin and often a pinkish eye color. Other forms of albinism may affect only the eyes. These individuals will present with many of the eye and vision problems related to albinism, but have normal skin and hair pigmentation.
Effects of Albinism
Reduced Vision & Macular/Foveal Hypoplasia: Patients with albinism have reduced visual acuity primarily from an underdevelopment of the center of the retina. The macula is where the best vision is located and it contains a very sensitive area called the foveal pit. The pit fails to develop in albinism and causes mild to moderate reduction of central vision.
Photophobia: The melanin pigment absorbs stray light and protects our eyes and skin from ultraviolet light. This pigment coats most of the internal layer of the eye allowing light to enter only through the pupil, and the pigment in the retina normally absorbs stray light. Failure of the eye to develop pigmentation in albinism results in extreme light sensitivity. Thus the patient may not only have too much light entering the eye, but also have no way to handle the excess stray light once in the eye.
Sunburn: Patients with albinism are at risk for severe sunburn. Children must be taught to protect their skin. Sunscreens and adequate clothing are essential. Sun may pass through clothing, especially wet clothing, and burn the skin. Increased risk of sunburn occurs at higher altitudes, and may occur at lower latitudes around reflective surroundings such as sand and water.
Nystagmus: In congenital forms of vision loss it is common for patients to have nystagmus. Nystagmus is an involuntary rhythmic oscillation of the eyes. It is often the first sign that parents recognize an infant has a vision loss. Nystagmus can occur in many forms and can lead to a decrease in vision just from the rhythmic movement.
The Null Position - Unusual Head and/or Eye Position: Patients may also show a tilt or turning of their head or eyes to where they achieve their best vision. This is called the null position. It is crucial that family and teachers allow a child with albinism to tilt or turn their head or eyes to the position that lets them see the best. When bifocals are prescribed, the low vision specialist must select the type and position that works with the patient’s null position.
Fluctuating Vision: A patient’s nystagmus often fluctuates when under stress or when tired or fatigued. As the nystagmus increases, the vision may blur further. Children with nystagmus may not do well with timed tests that may place the child under stress. Even covering one eye may cause a change in the vision of the viewing eye due to an increase in nystagmus.
Strabismus (Crossing or turning out): The loss of binocular vision is common in albinism, and this results in reduced depth perception.
Stable Condition: Albinism is a stable condition. In fact, some patients show slight improvement in visual acuity by the time they are young adults. This may be related to increased pigmentation or a better control of the nystagmus.
Systemic Issues: Albinism has been linked in rare cases with systemic diseases. The most common is Hermansky-Pudlak Syndrome (HPS). HPS occurs throughout the world, but is most commonly associated with patients of Puerto Rican descent. Abnormalities of the granules in the blood platelets cause a bleeding disorder and an accumulation of a chemical called ceroid. Lung and gastrointestinal problems may develop including the inability to full expand the lungs and colitis. To diagnose HPS, the electron microscope must be used to examine the blood platelets. The Hermansky-Pudlak Syndrome Network, Inc. may be reached by Internet at www.medhelp.org/web/hpsn.htm . Albinism has also been associated with Chediak-Higashi Syndrome (CHS), Prader-Willi Syndrome and Angelman Syndrome.
Emotional Aspects: Patients with albinism must deal with the emotional aspect of appearing different. Pink skin and eyes, white or platinum hair, unusual head or eye null positions, thick eyewear and the need to hold reading material very close unfortunately cause these patients to stand out more. Adding to the problem, Hollywood has frequently exploited albinism in movies picturing “albinos” as evil or sinister characters. The Albinism in Popular Culture web site at www.lunaeterna.net/popcult/ discusses how albinism has been viewed by society.
Low Vision Care
Low Vision Care for Albinism: Patients with albinism are excellent candidates for low vision care. Albinism is a mild to moderate, stable central vision loss. These patients have excellent residual side vision. Simple magnification, correction of refractive errors, light and glare control and use of adaptive aids may all benefit albinism patients.
Filters & Sun Protection: Tints, selective filters and hats may aid the albinism patient. The low vision specialist must consider the need for adequate filters both inside and out. Sunlight may be 100 times brighter than inside light. Filters for general wear are usually not adequate for outside wear. Some patients may benefit from Transitions Xtra lenses that darken in the sun. Additionally, adequate education on the use of sunscreens, hats and clothing is necessary in all albinism patients.
Refractive Error: Albinism usually results in significant amounts of farsightedness or nearsightedness combined with astigmatism. Most albinism patients require prescription eyewear. Refracting the nystagmus patient requires special techniques to reduce stress and avoid increasing the nystagmus. Every child with albinism should be carefully refracted by the low vision specialist at an early age.
Close Reading Distance: With a mild to moderate loss of visual acuity, an albinism patient may require holding materials closer. Parents and teachers often worry about the close distance, but the patient should be allowed to read at the distance where they see the best. Most albinism patients benefit from bifocals to reduce the strain of focusing at such a close distance. Bifocals should be considered in all school age children with albinism.
Reading Vision: At an early age bifocals may help patients with albinism by reducing fatigue and eye strained caused by the very close working distance. Magnifiers, strong reading glasses and closed circuit television system may be helpful.
Contact Lenses: Contact lenses can be used to correct the refractive error (myopia, farsightedness and astigmatism) of an albinism patient and in some cases an improvement in visual acuity is obtained. Contact lenses have been shown to aid some patients with nystagmus. One theory is that the tactile feedback of feeling the contact lenses on the eyes may lead to better control of the movement and allow the patient better vision. Another benefit of contact lenses is that they move with the eyes and provide better image quality.
Bioptic Driving: The vision loss from albinism is moderate and is usually a stable condition. Albinism patients are usually excellent candidates for bioptic driving. Bioptic driving requires the use of a bioptic telescopic system for spotting signs and lights. Extensive training is required to make sure the patient is using the bioptic correctly and that his/her skills behind the wheel are adequate. NOAH, National Organization of Albinism and Hypopigmentation, offers an Internet discussion group on bioptic driving. There web site is at www.albinism.org.
Support and Information About Albinism
NOAH, the National Organization of Albinism and Hypopigmention (NOAH) is a wonderful resource for information on albinism. They have handouts on all aspects of albinism and offer periodic national meetings that serve both as educational experiences and also an opportunity for individuals with albinism and their families to meet.