Focus On Low Vision
Combining CLs with low vision devices
By Barbara Anan Kogan, OD

Contact lenses for low vision patients? Yes, say some specialists, who combine them with a variety of low vision devices. Here is how three contact lens specialists--a corneal ophthalmologist, an optometrist, and an optician-- collaborate with two low vision optometrists and a low vision optometrist-trained vision rehabilitation coordinator to use a combined-device modality.

Duke University's Contact Lens Service director B.W. Phillips, FCLSA, and vision rehabilitation coordinator, Deborah Lapolice, MS, both use a combination of GP contact lenses and low vision devices and strategies to improve the quality of life of their low vision patients.

Those patients range from children born with congenital retinopathy of prematurity to recently diagnosed seniors with progressive age-related macular degeneration or glaucoma.

Eyes Cream Shades style Marshmellow provides side protection for kids' eyes

USING GP CONTACTS

For the keratoconus, macular degeneration, or glaucoma low vision patient, reports Lapolice, "their main request is to enable them to 'see the way I used to see things.' These patients have to learn to do tasks in alternative ways, which requires additional time when working with GP and low vision devices."

Describing their patient base, Phillips says, "Some 60 percent to 70 percent of our contact lens patients include traumatic cataract and retinal injuries, which cause unilateral low vision and anisometropia. Wearing a GP contact lens helps to improve visual acuity, peripheral vision, and depth perception, but requires more adaptation."

"When fitting GP contact lenses, the overall diameter should be approximately 1.0 mm smaller and have a good Dk," Phillips says. "GPs will gravitate to the steepest meridian and more toward the inferior position." As the cone progresses, he also advises fitting replacement GPs from the same lab for consistency.

ADDING DEVICES

Among the low vision device appliances Lapolice suggests for GP wearers are "use of a 5X mirror, putting the contact lens case on the tray of a closed circuit TV (CCTV) so the patient can locate it more easily, or using a Luxo-type lamp with magnification and fluorescent lighting where the patient can place it at any angle for handling their contact lenses."

Low vision patients with significantly decreased acuity frequently require an additional pair of eyeglasses or magnifier over the GP contact lens for reading. Among the newest technologies is an electronic, head-mounted distance and near-system CCTV that magnifies objects up to 30 times.

Discussing his use of GP lenses for low vision patients, corneal specialist and former CLAO president Gary N. Foulks, MD, director of Cornea and External Disease Services at the University of Pittsburgh Medical Center's Eye and Ear Institute, says, "With corneal degeneration or dystrophies, GP contact lenses can do a lot to help with visual rehabilitation and balancing the patient's binocularity." As conditions progress and there is an anisometropia, he fits patients with monovision GPs to help improve visual function.

	A dome reader from Eschenbach

THE RIGHT COMBINATION

While at Duke University, Foulks recalls fitting "a high minus lens on the cornea and combining it with a pair of aphakic eyeglasses to create a telescopic system." Currently, Foulks stresses that a good relationship between the ophthalmologist and low vision optometric specialist can "improve the patient's overall vision functioning."

Cholappadi V. Sundar-Raj, OD, PhD, also at the University of Pittsburgh, offers several examples of combining GP contacts with low vision devices.

Sunglasses. A young patient with a large pupil was complaining about seeing rings around lights. Sundar-Raj combined GP specialty keratoconus designs and a polarized sunglass with a gradient shade first, followed by a 10 percent gray tint.

Filters. If a patient complains about difficulty seeing in the dark, he gives them a yellow filter to wear in glasses over their GP contact lenses. And, when a monocular cataract develops and the patient complains about difficulty night driving, Sunder-Raj prescribes this same yellow filter.

Loupes. For the post-surgical high myope who has had a retinal detachment, he prescribes a monocular hand-held loupe to be used with the GP contact lens for walking around. "A fingertip telescope ground into a polycarbonate frame can be aligned with the loupe," he adds.

Magnifiers. For reading, a 2-4X roll-on magnifier can be used with GP contact lenses and moved over a page of printed material. Sunder-Raj has also had success in eliminating distortion by using a 12-diopter, hand-held magnifier with two lenses fused together.

A 5X mirror from Lighthouse International

WHAT ABOUT KIDS?

Pediatric cataracts, leading to aphakia, is the most common reason Loretta Szczotka, OD, MS, director of Contact Lens Service at University Hospitals of Cleveland Department of Ophthalmology, fits infants post operatively with GP contact lenses. Among three- and four-year-olds, monocular ocular trauma from items like hangers, pens, or pencils is a common problem for which she recommends contact lenses.

"Unlike those with congenital cataracts, these children have had very good vision potential with GP lens use because they develop visually prior to their ocular trauma. GP lenses are required in this population because of the corneal irregularity induced from the trauma."

When there are still visual defects once the contact lens treatment has been completed, a low vision specialist is consulted to provide the next level of care. Cheryl J. Reed, OD, director of Low Vision Services at United Disability Services, is an advocate for early intervention, especially as a component of a multidisciplinary team.

In the case of albinism or cone dystrophy that causes extreme light sensitivity, she says children may benefit from very dark-tinted prescription lenses in a close-fitting, wrap-style frame. And, the tinted lenses may need to be as dark as five to seven percent light transmission in bright sun and 10 to 15 percent light transmission in bright indoor conditions.

"Children as young as four also benefit from monocular or binocular telescopes to help them to see detail at a distance," adds Reed. "They often get very excited when they first try a telescope because it is the first time they have ever been able to see a sign across the street or a bird in a tree."

It is also important for children to be able to see print easily when learning to read. "Magnifiers, high-add reading glasses, or closed circuit television systems can be used to enlarge print. Though some children find it difficult to use hand-held magnifiers because their accommodation fluctuates. Many find the 2X-4X dome magnifiers easiest to use because they stay in focus and provide a nice field of view," she explains.

Reed also encourages her young patients to borrow low vision aids for trial use at home and in the classroom before final recommendations are made.