Visual impairment is a common condition that affects more than 12 million adults over age 40 in the United States. But low vision—a condition that affects one in six adults throughout the nation—is different. People with low vision have reduced visual acuity (the common clinical measure of eye function) that cannot be corrected by standard glasses, contacts, medication, or surgery.
Leannza Tang, OD, an optometrist and Director of Low Vision Services at New York Eye and Ear Infirmary of Mount Sinai, explains low vision rehabilitation and what patients can do to seek care.
What causes low vision? What are the symptoms?
Low vision can be caused by many different eye conditions. Some of the more common include glaucoma, macular degeneration, and diabetic retinopathy, but there are other conditions that can lead to vision loss as well.
The most common symptom is blurry vision that cannot be corrected or improved with standard eyeglasses, contact lenses, or eye surgeries. This usually translates to difficulty seeing small print. Patients may have difficulty reading a book; seeing a sign from a distance that they used to be able to; or even watching television.
Some people have distorted or missing spots in their central vision. This might make seeing people’s faces a lot more difficult. Other times, patients report side vision loss, which is what we typically see in glaucoma patients. When someone has severe side vision loss, this can affect their mobility. Walking around as well as navigating stairs and curbs can be very difficult. These patients are prone to bump or trip over things.
Leannza Tang, OD
Are all low vision patients considered legally blind?
This is a common misconception about low vision patients that may not be true. Legal blindness is defined as someone with a visual acuity of 20/200 or poorer and/or has a visual field of no more than 20 degrees in their better seeing eye. Therefore, not all low vision patients are considered legally blind.
Eye care providers can clarify if you meet the criteria for legal blindness during your eye exam.
What is the difference between a low vision exam and a routine eye exam?
My low vision exams can be very different from a routine eye exam. One of the first things I tell patients is that I’m focused more on how they’re functioning day-to-day. Typically, the results of different scans, side vision tests, eye pressure tests, and dilations are all being managed by their ophthalmologist or optometrist so therefore, it is still very important to follow up with them as instructed.
I am interested in finding out what the patient’s goals or complaints are in relation to their vision. Are they having difficulty reading small print? Are the issues apparent when looking at price and medication labels or when reading a book and watching television? Do they have problems seeing street signs or bus numbers? The list goes on. I typically meet with patients for about one hour in which we discuss how to manage the condition and what devices might make navigating day-to-day life easier.
How do I manage low vision? Will the condition get worse?
I recommend seeing a low vision specialist. Many people think that you need to wait until you have severe vision loss before seeing a specialist but that is not true. Low vision physicians see a range of patients, from profound to more mild vision loss.
Low vision specialists can discuss any additional services that may benefit a patient. This includes orientation and mobility training for those who are having difficulty walking around or traveling independently because of their vision loss. There is training for household tasks like cooking, doing laundry, housework, and so on. There is also training to more efficiently use your personal devices including computers, smartphones, and laptops. If patients already have these devices, a specialist can teach them how to use built in accessibility and other features that might benefit them.
I also show low vision devices to see if they’re suitable to help a patient with their day-to-day tasks. This includes:
- A hand magnifier is probably the most common and familiar low vision device. Hand magnifiers make text bigger and are mostly for spot reading tasks like reading price labels or medication labels. Stand magnifiers are best for if you want to sit down and read a book for an extended period of time. To use it, you slide the device over your reading material while sitting at a desk or table. They come in different magnification powers, so I recommend a low vision evaluation to make sure that you are using the most appropriate device and power.
- Digital magnifiers operate very similar to stand magnifiers. These magnifiers allow you to adjust how big you want the words to appear as well as the color of the text for ease of viewing and reading.
- If patients are having issues seeing objects at a distance, like bus numbers or street signs, we can prescribe telescopes. We can do in-office training so that patients are able to use the device efficiently and comfortably.
It is very difficult to say whether someone’s vision will or will not get worse over time. It really depends on the person’s underlying condition that is causing their low vision. I will stress that it is important to follow up with the provider who is managing your eye condition and continue to take your prescribed medications and eye drops as instructed.
What resources are available for people with low vision?
Dealing with vision loss, whether sudden or gradual, can be very difficult. Some patients express feelings of sadness, frustration or anxiousness. A referral for behavioral health resources can be made to ensure a patient has the support they need.
Mount Sinai has excellent low vision resources. To learn more about low vision services at New York Eye and Ear Infirmary of Mount Sinai, please speak to your eye care provider or visit our website.