Awareness is key to spotting these treatable symptoms
“This study confirms a lot of what we already knew about Parkinson’s disease, but it gives more numbers to it and also the patient’s perspective rather than the doctor’s perspective,” Andrew G. Lee, MD, commented in an interview. “We know that patients with Parkinson’s disease have a lot of ophthalmologic symptoms – probably more than we recognize or ask about in the clinic – and their symptoms predominantly are out of proportion to what we see on exam,” said Dr. Lee, who is chairman of the Department of Ophthalmology at Blanton Eye Institute, Houston Methodist Hospital.
In fact, patients may have normal acuity, normal visual fields, and a normal structural eye exam, yet still report vision problems because of the central neurodegeneration occurring, he noted. “Ophthalmologists cannot rely on just the eye exam when examining patients with Parkinson’s disease. They have to take symptoms into consideration. It’s really important to be aware of how brain disease can affect the eyes symptom-wise, even though the eye exam is normal.”
Administering the questionnaire used in the study is not very difficult but is somewhat time consuming, so most ophthalmologists and neurologists are unlikely to use it, according to Dr. Lee. But knowing common symptoms and asking about them can ensure they are promptly recognized, the first step in addressing them.
“None of the visual complaints in patients with Parkinson’s disease are curable because Parkinson’s disease is not curable and the disease is the underlying major etiology for the problems. However, all of the symptoms have treatments,” he said.
For example, dry eye, caused by decreased blinking, can be treated with drops. Convergence insufficiency, which generates double vision when focusing on nearby objects, can be managed with prisms, exercises, and if needed, eye muscle surgery. Impaired eye movement is best treated with different sets of glasses specific to tasks, such as one pair for reading and one pair for distance. And visual hallucinations can be addressed with changes to existing medications or new medication, or simple reassurance that the hallucinations aren’t harmful.
“It’s important that this kind of study increases awareness in the medical community,” concluded Dr. Lee, who disclosed no relevant conflicts of interest. “The take-home messages are that eye doctors know that these are real complaints, that the eye exam is not going to give the answer, and that all of the symptoms have treatments even though there is no cure.”
SOURCE: Borm CDJM et al. Neurology. 2020 Mar 11. doi: 10.1212/WNL.0000000000009214.