Glaucoma is usually described as a disease affecting peripheral vision. So, it wouldn’t have any effect on reading, the ultimate task of central vision, right?
In fact, glaucoma does affect reading. Why? First, while glaucoma does affect peripheral vision, it also affects central vision. Glaucoma patients with moderate or severe disease often describe looking through a fog which extends into their central vision. Because of this fogging, people with glaucoma recognize fewer letters in one glance. They must therefore look at text more times to make their way through a passage. The result is slower reading and particular difficulty with longer words.
Second, reading also brings in one’s mid-peripheral vision. For example, we use our field of view when moving from the end of one line to the start of a new line of text, or when searching a page of information for the specific details we wish to learn about. Glaucoma patients have particular difficulty with these aspects of reading.
Even when glaucoma patients can read, it is more difficult. Over long periods of time, individuals with more severe glaucoma tire, and their reading speed slows. They also understand less of what they read. Because of all these difficulties, persons with glaucoma read less often. As a result, they may become less independent and more disconnected from the world.
So, while we continue to fight for treatments that restore vision, what can be done to make reading easier for those with glaucoma? You can start by trying some things on your own.
Increase the text size when working on the computer or other electronic devices.
Use spot lighting when reading a book.
Consider reading on a tablet or other device that enables reverse polarity (white letters on a black background instead of black letters on a white background).
These tips are not so easy to perfect on your own. So, if you’re having trouble reading and haven’t seen a vision rehabilitation specialist, ask your doctor for a referral. These professionals specialize in helping you live as functionally and independently as possible with the vision that you have.

Article by Pradeep Y. Ramulu, MD, PhD. Dr. Ramulu is an Associate Professor of Ophthalmology at Johns Hopkins, and Director of the Glaucoma Service at the Johns Hopkins Wilmer Eye Institute. His research is focused on how visual damage from glaucoma and other diseases affect the individual, and how we can maximize independence and safety for patients who have lost vision from glaucoma.