Contact Lens Case Reports
A Special Case of Albinism
BY PATRICK J. CAROLINE, FAAO, & MARK P. ANDRÉ, FAAO
Albinism is an inherited congenital disorder characterized by the complete or partial absence of pigment in the skin, hair, and eyes. The condition is known to affect all vertebrates on the planet and is due to an absence or defect of tyrosinase, a copper-containing enzyme involved in the production of melanin. In humans, there are two types of albinism—oculocutaneous, affecting the eyes, skin, and hair, and ocular, affecting the eyes only.
Most people who have oculocutaneous albinism appear white or very pale as the melanin pigments responsible for brown, black, and some yellow colorations are not present. Ocular albinism results in pale blue eyes, and may require genetic testing to diagnose. The ocular ramifications of albinism can include photophobia, nystagmus, and reduced visual acuity.
The Patient's Profile
Our patient is a 5-year old female who has oculocutaneous albinism. Her general health is excellent. Her refractive error is essentially plano in both eyes with a visual acuity of 20/100 OU. Her anterior segment examination showed iris translucency by slit lamp retroillumination, and her posterior segment examination revealed bilateral fundus hypo-pigmentation, optic nerve hypoplasia, and foveal hypoplasia (with an absence of focal reflex). Together, these ocular findings resulted in eccentric fixation, strabismus, and a significant decrease in visual acuity.
By parental history, the patient's primary ocular problems included congenital nystagmus and extreme photophobia. In normal eyes, the retinal pigment epithelium absorbs much of the reflected sunlight, but in albinism, the lack of retinal pigment increases light scattering within the eye, resulting in significant symptoms of glare and photophobia. This symptom in these patients has typically been managed with sunglasses and/or brimmed hats.
In 2012, the patient was referred to our clinic for possible cosmetic tinted lenses to decrease light transmission through the iris. The patient was fitted with custom soft contact lenses manufactured by Alden Optical: HP 49 material, 8.4mm base curve, plano sphere power, 13.8mm diameter, and 12.0mm annular black opaque iris zone with a clear 3.5mm-diameter pupil (Figures 1 and 2).
Figure 1. Patient with the opaque tinted scleral contact lenses.
Figure 2. High magnification view of the opaque tinted soft contact lenses for albinism.
The child tolerated the lenses extremely well, and within one week she was up to all-day lens wear. The parents reported an immediate improvement in the child's social and developmental behavior. Her indoor and outdoor photophobia had dramatically lessened, and while her visual acuity remained unchanged, the parents and teachers reported much improved functional acuity both at home and at school.
Some patients may continue to experience some degree of photophobia. In these cases, the clear 3.5mm pupil can be tinted with an additional pigment (gray, brown, yellow, or red) to further decrease transparency while maintaining a functional pupil diameter.
Successfully treating patients who have albinism can offer them life-changing benefits. CLS
Patrick Caroline is an associate professor of optometry at Pacific University. He is also a consultant to Contamac. Mark André is an associate professor of optometry at Pacific University. He is also a consultant for CooperVision.