Contact lenses can help patients with low vision

Contact lenses generally are not combined with low-vision rehabilitation; the two are seen as different entities in the profession of optometry. I have had the joy and privilege of working as a contact lens and low vision specialist, and the intersection of care has been profound. There are myriad ways to utilize contact lenses for patients with low vision to maximize rehabilitation and quality of life.

High refractive error

The low-vision clinic welcomes patients with vision loss from progressive degenerative myopia that yields a large myopic prescription, as well as patients who are aphakic, which leads to a very high hyperopic prescription.

There are jokes about the “Coke bottle” glasses for our patients with high refractive error, and as silly as the jokes may be, thick spectacles can create several issues for patients. They can cause distortion, minification, limited field of view, make the eyes appear bigger or smaller, and put stress on the nose bridge due to the weight.

These problems can be rectified easily with contact lenses. Many companies create custom soft contact lenses for patients with high refractive error. CooperVision has lenses that cater to prescriptions as high as –20.00 to +20.00 diopters with the Biofinity and Proclear lenses.¹ Bausch + Lomb also has a range of custom soft contact lenses called Revive that enable prescriptions even higher (–30.00 to +30.00).² There are dozens of specialty contact lenses on the market with great customer service, allowing an easy fitting process for patients with low vision.

Ocular albinism

Patients with ocular albinism come to low-vision clinics due to congenitally reduced vision. They are monitored starting at an early age to augment their education with specialized low-vision gadgets.

Two of the most common symptoms patients with ocular albinism face are glare and nystagmus. Sensitivity to light, glare, and nystagmus are related to overstimulation of a hypopigmented retina for persons with ocular albinism.³

Due to the lack of opaque pigment in the iris, glare can be debilitating in bright environments without sunglasses or tinted fitovers. Colored contacts or prosthetic contacts can be customized with an opaque iris to reduce the entrance into the pupil, which eases symptoms.⁴

To accommodate the patient’s lifestyle and needs, the iris occlusion size can be changed to allow more light or less light to enter the eye. It has been demonstrated that wearing sunglasses and occlusive contact lenses reduces the amplitude of nystagmus, giving the patient an improved capacity for visual function.⁵

Specialty contact lenses are usually changed every 3 to 12 months, which could be challenging for a child learning to use contacts for the first time. In this situation, beginning with a monthly colored lens like Air Optix Colors (Alcon) to improve lens handling and comfort before investing in a specialty lens has been beneficial and liked by parents.

Ocular trauma

Significant ocular damage frequently leaves patients with altered aesthetics of their eyes or eyelids as well as residual vision loss. Chemical burns, mechanical injury from a foreign object, congenital deformities, infections, and surgical complications following phacoemulsification, corneal transplant, or glaucoma surgery are a few examples of ocular trauma.

The social repercussions of ocular trauma, particularly for individuals with considerable vision loss, have a crucial role in the patient’s mental health and capacity to interact with others as normally as possible. These patients are evaluated at the low-vision clinic and are usually seeking rehabilitation to improve visual function and ability to perform daily tasks. With the potential to offer cosmetic relief to patients, it may improve their quality of life more than anticipated.

For patients undergoing enucleation, the best option would be a scleral shell, which is inserted inside the eye socket to aid in maintaining the form of an eyeball. Optometrists and ocularists can offer this service to patients, customizing the iris color and form.

Both soft and rigid gas-permeable prosthetic contact lenses are available, and numerous companies provide these services. To create a more seamless fit process, it is advised to establish a partnership with a business for collaborating on complicated fits.

A wide variety of soft prosthetic lenses that may be customized are offered by companies like Cantor & Nissel,⁶ along with a helpful color match guide that can be delivered to the office to engage patients. An example of change with a prosthetic contact lens is shown (Figure). After a traumatic accident, the right cornea opacified; with the aid of a hand-painted soft contact lens, the symmetry of the eyes was cosmetically restored.⁷

Although a change in appearance may not restore damaged vision, it can certainly aid in restoring lost confidence. The simplest method for learning more about the fitting procedure is to contact a representative from a prosthetic lens manufacturer. You will be surprised at how manageable it is.

UV lenses for age-related macular degeneration and cataracts

A large percentage of patients with low-vision issues have vision loss secondary to age-related macular degeneration (AMD). Due to their advanced age, many such patients may also have cataracts. Many patients with mild to moderate macular degeneration enjoy wearing contact lenses for certain outdoor activities or special events. For patients who would like to supplement contact lens wear with spectacle wear, some recommendations can be made to benefit their eye health.

Sunglasses with UV-A and UV-B protection are the standard recommendation. Having said that, contact lenses can offer further UV protection, particularly indoors where most patients are not wearing sunglasses but UV rays still enter through windows and doors.

Examples of accessible contact lenses offering this protection include Acuvue (Johnson & Johnson) and Biotrue ONEday (Bausch + Lomb). A contact lens that offers some level of UV protection may be preferable to one that may not, given that UV has been associated with an accelerated progression of cataracts and AMD.^8,9

Contact lenses cannot replace protective sunglasses. Contact lenses that provide UV protection may create a false sense of security that the eyes are adequately protected. Contact lenses protect the cornea, but many other parts of the eye, such as the conjunctiva, eyelids, and surrounding skin, are left exposed. It is imperative that eye providers educate patients about the advantages and the limitations of UV protection in contact lenses.

Contact lenses might be overlooked as a source of rehabilitation for patients with low-vision needs. Optometrists are the only health care professionals with such extensive expertise and experience regarding contact lenses, so it is our responsibility to provide contact lenses as an option to improve quality of life when appropriate.

The joy that comes from being able to offer services that solve multifactorial visual impairments using equipment ranging from specialty contact lenses to low-vision rehabilitation tools is what makes each long day so rewarding.

References

1. Biofinity & Biofinity XR. CooperVision. https://coopervision.com/practitioner/our-products/biofinity-family/biofinity-biofinity-xr

2. Revive custom soft lenses. Bausch + Lomb specialty vision products. https://www.bauschsvp.com/lenses/revive-custom-soft-lenses/

3. Cheong PY, King RA, Bateman JB. Oculocutaneous albinism: variable expressivity of nystagmus in a sibship. J Pediatr Ophthalmol Strabismus. 1992;29(3):185-188. doi:10.3928/0191-3913-19920501-14

4. Omar R, Idris SS, Meng CK, Knight VF. Management of visual disturbances in albinism: a case report. J Med Case Rep. 2012;6:316. doi:10.1186/1752-1947-6-316

5. Biousse V, Tusa RJ, Russell B; et al. The use of contact lenses to treat visually symptomatic congenital nystagmus. American Journal of Ophthalmology, vol. 137, no. 5, 2004, p. 972., https://doi.org/10.1016/j.ajo.2004.02.085

6. Cantor + Nissel. www.cantor-nissel.co.uk/

7. Cassel M. Prosthetic eye options. Contact Lens Spectrum. December 1, 2019. https://www.clspectrum.com/issues/2019/december-2019/prosthetic-eye-options

8. Chalam KV, Khetpal V, Rusovici R; Balaiya S. A review: role of ultraviolet radiation in age-related macular degeneration. Eye Contact Lens. 2011;37(4):225-232. doi:10.1097/ICL.0b013e31821fbd3e

9. Linetsky M, Raghavan CT, Johar K; et al. UVA light-excited kynurenines oxidize ascorbate and modify lens proteins through the formation of advanced glycation end products: implications for human lens aging and cataract formation. J Biol Chem. 2014;289(24):17111-17123. doi:10.1074/jbc.M114.554410