Eyes as diagnostic tools for PD?

Yesterday, John & I enjoyed a lunch with two other Parkies and their spouse/ caregivers. Ed & Jane have put together a slide show presentation giving hints and tips for living with Parkinsons. I looking forward to attending the discussion. They are currently writing a book telling about their Journey. Jane had early onset PD… so the illness progresses more slowly, but after 30 years She now has two Deep Brain Stimulators in her brain and is in a wheelchair. They recommended the place in Gainsville I had gone to once. And Rose, who puts together a weekly newsletter for the parkinson’s group, gave me the name of the Movement Disorder Specialist her husband, John, sees and they recommended. I called to see if I could get an apppointment with her. But was told that they couldn’t allow me to switch doctors after I’ve already seen one. But after further discussion, she said she would pursue my request, so I am hopeful.

And now I know what I want for my birthday. After the ladies shared their experience with UTI’s… Something I recently completed receiving a round of antibiotics for… Jane said, The doctor said the best way to quit having the problem was to get a good Bidet. One that doesnt have plastic valves.. make sure the hardware is metal and it has a heater for the water. The one they got also has a nightlight built into it. They said expect to pay at least $300. for a good one, They run as high as $900. + or as cheep as $39.

Jane, like I, experiences eye challenges. She has to use a VERY Large font to enable her to type. They recommended I go see a neuro-ophthalmologist. I pointed out, there are none in the Lady Lake or The Villages. They knew of a good one… in Gainsville, of course.

<><><><><><><><><><><><><><><><><><><>

As I was brousing the Parkinson’s News Today, I saw this article:


 Eyes’ Pupils May Be Window Into Assessing Disease Stag

The response of the eyes’ pupils — the black circle in the center of the eye  that allows light to enter — seems to change according to the progression of Parkinson’s disease, a recent study has found.

The results suggest that measuring the pupils’ response to stimuli could become a noninvasive way to measure disease progression.

The study, “Analysis of pupillometer results according to disease stage in patients with Parkinson’s disease,” was published in Nature: Scientific Reports.

The pupil is the hole situated in the center of the iris (the colored part of the eye) that allows light to enter the retina, a lining of tissue at the back of the eye that is sensitive to light.

The iris is a contractile structure, and expands or dilates depending on the amount of light available. In this way it regulates the amount of light by controlling the size of the pupil, functioning like a photography camera’s aperture. This movement is known as the pupil light reflex (PLR) and plays a key role in determining the eye’s image quality and response to light.

A team of researchers in South Korea looked at the PLR using a pupillometer, an instrument used to measure pupil response to light. This reflex allows one to assess the functionality of the autonomic nervous system — the part of the body that controls involuntary actions such as digestion and heartbeat.

The sympathetic system activates several bodily functions when an imminent threat or major stressor is perceived, while the parasympathetic system works to calm the body afterward. Measuring the balance between these two systems can be a useful test for patients with neurological disorders.

In this study, patients with Parkinson’s were divided into early or late stages based on the Hoehn and Yahr scale (HY scale). Among the 132 patients, 100 were early stage (HY stages 1–2) and 32 were late stage (HY stages 3–5). After matching both groups for age and sex (to compensate for the effect of age on pupil light reflex), only 64 patients remained in the early stage group.

Those with late stage disease had longer disease duration and higher levodopa equivalent daily doses, meaning they were on higher doses of medications to treat their disease.

The study found there was a significant difference between the two groups in terms of pupil constriction velocity (the speed at which the pupil contracts when exposed to light) and maximum constriction velocity, which were significantly slower in the late-stage group.

“Constriction velocity and maximum constriction velocity are parameters involving the parasympathetic system, and changes in these parameters suggest that in patients with PD [Parkinson’s disease], the abnormalities of the PLR are mainly caused by parasympathetic autonomic dysfunction,” the researchers wrote.

There was not a significant difference in the two groups when it came to pupil dilation velocity (how quickly the pupil dilates when light is removed), baseline pupil size, minimum pupil diameter, and constriction latency, the delay in pupil constriction following light stimulation — all parameters that involve the sympathetic system.

The researchers noted that pupillary dilation response may have not been affected because the medications that the patients were taking may have affected the sympathetic nervous system, and thus offset the progression of the disease on dilation response.

“[T]he parameters measured by pupillometry changed according to the motor progression of PD,” the researchers wrote, adding that “pupillary parasympathetic dysfunction progresses with the progression of PD. In contrast, the factors related to sympathetic dysfunction did not change much, implying that pupillary sympathetic dysfunction advances relatively slowly even [in] PD advanced.”

The authors thus suggest the progression of Parkinson’s disease could be identified measuring pupil constriction velocity

by Yedida Y Bogachkov PhD | September 24, 2021

Author: suerosier

In May of 2018, I was diagnosed with Parkinson's. After researching, I believe the symptoms began to manifest themselves years prior to last year. The purpose for my blog is to share what I have learned (with an index) to save others time as they seek for answers about, symptoms, therapies [and alternative things to try], tools I use, Parkinsonisms, recipes, strategies, clinical studies, words of encouragement or just enjoy the photos or humor.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: