“We need to remember that no two cases of Parkinson’s are exactly alike. No matter who you see or know with PD, or what you hear or read about PD, you are not necessarily going to be like that or have happen to you what has happened to them, because you are unique and so is each case of PD.”
NANCY F., PWP
If you’ve ever wondered if Parkinson’s can affect your vision, the answer is yes, it can. Problems with vision can occur as a symptom of the disease and/or as a side effect of medications.
You might find that your upgaze—your ability to look up at things like signs that are above you—is not very good. Some people also experience difficulty adjusting to changing light levels and find it hard to see at night.
Blurry vision can be a side effect of anticholinergics (drugs used to control tremor). It can also be caused by the lack of blinking that occurs as a symptom of the disease.
Mom went through a phase where she had problems with double vision. She noticed this mostly when she was looking at something up close. For example, when she wrote, she often saw two of the same letter. Though her doctor never confirmed that her double vision was related to her PD, she had several tests and no other reason was found.
After doing some research of our own, we found that double vision can occur in people with Parkinson’s. When the brain stem starts to degenerate, dopamine levels fall. This can cause a lack of basic eye coordination called “convergence insufficiency,” Convergence insufficiency becomes most noticeable when reading, and people may experience symptoms ranging from eye fatigue to double vision.
So what did my mom do about it? Well, one thing that helped was closing or covering up her nondominant eye. If you think this might look a bit awkward, there are ways of covering up an eye that are barely noticeable to other people. You can find translucent patches online that go over one lens of your glasses and can help to correct blurry or double vision. If you are worried about budget, then applying clear nail polish directly to part or all of one of the lenses might be enough.
Another recommendation is to try prisms, which are special lenses that help keep the eyes in alignment. Permanent prisms can be incorporated into an eyeglass prescription, and temporary ones that you paste on yourself, called Fresnel lenses, are available online to try.
Strangely, as Mom’s PD progressed, her double vision went away.
If you were to tap on the glabella (the area between the eyebrows, just above the nose) of someone who does not have Parkinson’s, first they would start blinking, but then they would stop blinking even if you kept tapping. With some Parkinson’s patients, if you were to tap on this same spot, they would continue to blink and not be able to stop. This is known as Myerson’s sign, which is also often referred to as glabellar reflex.
Adapted from the book Complete Guide for People with Parkinson's
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