As we grow older, it is normal to experience age-related eye problems. These changes usually have nothing to do with Parkinson's disease (PD). If you are having vision problems, it is important to visit an ophthalmologist first. However, there are some vision changes that may be due to PD:
- Double vision can occur due to medications or because the eyes have trouble working together, (convergence insufficiency). Special prism glasses can correct this.
- PD can cause dry eyes and decreased blinking.
- PD medication, especially anticholinergics, can cause blurry vision. There is a relationship between anticholinergic medication (trihexyphenidyl ― formerly Artane® or benzotropine ― Cogentin®) and dementia.
- Trouble reading, because eye movements necessary to follow the lines of a page are slowed and have trouble starting (similar to gait freezing in the legs).
- Blinking to change eye position. Levodopa can help.
- Trouble voluntarily opening the eyes, known as apraxia (treated with "lid crutches" or botulinum toxin injections).
Some people with PD notice as the disease progresses their vision loses sharpness. Difficulties related to the eyes and vision often progress alongside other PD symptoms.
Tips for Managing Vision Changes
- Regularly see your ophthalmologist for an eye examination.
- Get two pairs of glasses, one for distance, one for reading. This may be better than bifocals. Ask your ophthalmologist if prescribing prism glasses can help.
- Apply warm moist compresses or ointments for eyelid irritation.
- Use artificial tears to moisten dry eyes.
- Consider adding a neuro-ophthalmologist to your medical care team. This is a specialist, either an ophthalmologist or a neurologist, who has additional training in diagnosing and treating eye and vision problems associated with PD and other neurological diseases.
Uncommon Vision Conditions
It is not common for people with PD to experience involuntary closure of the eyes, but it does occur in some cases. This phenomenon is known as Spasmodic winking caused by the involuntary contraction of an eyelid muscle.. Blepharo refers to the eyelid, and spasm is defined as an uncontrollable muscle contraction.
There are many conditions that can cause involuntary eye closure. These conditions are not related to PD. They include:
- An inflammatory eye condition due to an infection or an allergy
- Dry eyes
- Damage to the surface of the eye
- Ptosis (when a person's eyelid appears to be drooping). It can be caused by muscle weakness, nerve damage or looseness of the eyelid skin, as in normal aging.
- Other conditions
If the ophthalmologist determines that the conditions above do not account for the eye closure, the next step is to see your neurologist to determine if the problem is related to your PD medications.
If eyelid closure remains a problem after medications have been optimized (optimizing your medications refers to a process in which you and your doctor work to find the medication regimen from which you derive the greatest benefit), then injection of botulinum toxin (Botox®) every three to four months in the muscles around the eyelids has been found to be effective.
In rare cases, botulinum toxin may be ineffective and it may be helpful to consult a movement disorder specialist (MDS), a neurologist with expertise in movement disorders like PD. A MDS can help determine whether the diagnosis is correct.
Page reviewed by Dr. Chauncey Spears, Movement Disorders Fellow at the University of Florida, a Parkinson's Foundation Center of Excellence.