Whether you have one of the many ataxias or an ataxia compounded neurological diseases this article about VOR may help to answer some of your questions.
It was five years ago when I had my first vestibular-ocular event. It was a bright spring day and I walked into an army surplus store I had been to often. The store was dense with items to buy. The front of the store had fluorescent lighting that was bright but that light diminished as you moved deeper into the Quonset-like building. I got to the back and suddenly felt overwhelmed, somewhat disoriented, and off balance. I started to shake. I didn’t have any head or chest pain but the first thing my brain went to was that I was having a stroke.
Now, I am going to attribute the following to being a stereotypical “man-thing”. I left the building immediately, back into the bright sunshine and feeling more off-balance, and got into my car and drove the eight blocks to the urgent care centre. — See, kind of real dumb move.
After being with the attending physician for eight hours and submitting to numerous blood tests, vision tests, movement tests, x-rays, and a CT scan, I was released with an urgent appointment for an MRI in two days.
I met with a neurologist just before the MRI and was given some of the tests Ataxians and MSA, Parkinson’s, and PSP patients are used to: eyes closed balance (not good), heel-toe walk (not good), finger grasp (terrific), etc. I returned three days later to review the MRI results. The neurologist concluded that there was no evidence of stroke, thus I must have had a migraine attack. I have never had migraines in my 65 years so this was a surprise to me. The doctor was adamant. So started the next five years of progressively worsening balance, gait, visual, gastro, and movement disorders.
vestibular-ocular disorders associated with neurological diseases are not on the tips of doctors’ tongues
I share this story for two reasons. First, vestibular-ocular disorders associated with neurological diseases are not on the tips of doctors’ tongues when they are examining someone, especially someone over sixty. Neurological diseases are not simple and are often negated to exist by the medical profession’s reliance on the 14th-century rule: If you have competing ideas to explain the same phenomenon, you should prefer the simpler one (Occam’s razor).
Patients' story after story told on the NAF or MSA FaceBook pages reveals the long journey people must endure to get some semblance of a diagnosis finally. It took me three years of advocating for myself to actually gain a “possible” diagnosis of something. Ataxias, MSA, and other neurological diseases are complex requiring a holistic perspective by the medical practitioner. We have to advocate for ourselves to gain this perspective.
The second reason I share the story is that it highlights that most neurological research into ataxia and MSA acknowledges vestibular and vision issues but there is little in the way of describing the symptoms patients experience. I think this gives rise to the “Does anybody else here …” posts.
When a recent posting by Mike on MSA Coalition FaceBook described how his “gait/walking/balance issues” were “markedly different in different settings” I could immediately relate! Thanks, Mike! Like Mike, we both are pretty good at moving around our homes or other familiar smaller spaces. I felt kinship when Mike talked about using walls, furniture, and surfaces as touch points and proximity references. I do that at my gym as well. But get Mike and I outside or in a large building space then we wobble and are uncoordinated and clumsy.
Mike’s posting received nine comments from others all reporting similar sensations and reactions. The anxiety was evident in people’s posts. A few were reluctant to even leave their homes. Most noted that using walking sticks provided support for the decrease in balance and coordination in these spaces.
A woman shared that her husband was affected by changes in light, room width, and surfaces with stripes.
However, no one had an explanation and none of these symptomatic experiences have been widely reported in medical literature.
This vestibular-ocular disturbance is one of the most intrusive aspects of ataxia I experience. It is disruptive to movement, nauseating, and fatiguing. But what are we all experiencing and where does it fit in? The researcher in me wanted an answer.
After reviewing a substantial number of ataxia and MSA research papers, I found the same pat descriptions repeated. Patients exhibit vestibular disorders, vision issues including nystagmus, diplopia, and related gait and balance issues. Even knowing the meanings of these elements did nothing to illuminate (excuse the pun) why room size, light, surfaces, noise, and head movements seemed to trigger a greater ataxic movement response.
I found an article by Michael Schubert of the Vestibular Disorders Association (VeDA - #82) that looked at the situation from the vision and vestibular side. Schubert explains “vestibulo-ocular reflex” (VOR) as the system that keeps the eyes still when the head is moving. “Known as gaze stability…VOR also sends a signal down to the postural muscles of the trunk/arms/legs, which is crucial for maintaining balance.” For Ataxians, add in degeneration of the cerebellum, which already influences movement, gait, balance, coordination, and strength, and the issue just gets messy.
Here is what Schubert describes as patients’ experiences with a VOR disorder. The disorder can clinically present as nystagmus, oscillopsia, vertigo, and diplopia, along with gait, balance, and coordination issues. This, Schubert posits, translates into patients experiencing blurred vision during head movement, “illusions of motion in peripheral vision” (I thought I was seeing things over there!), and reduced clarity of vision when looking through progressive or bifocal lenses due to the lens shapes interacting negatively with the eye movements.
What I found that was most relieving was his list of possible environmental characteristics that could trigger our ataxic responses:
Photosensitivity ( bright light and darkness)
Flickering or strobing light (like walking through flickering shade)
Certain light sources found in stores including fluorescent, sodium, or mercury vapour lights.
Moving objects (and if it is moving and I am moving watch out!)
Rows of similar objects (the dreaded cereal aisle)
Lines of text in print or on-screen (I worked very hard to see the screen typing this.)
High-contrast patterns (crosswalk lines, polka dots, the annoying tile pattern design they used in the hallway leading to the new physiotherapy clinic at my hospital)
But what about those open spaces or busy spaces like Home Depot or the grocery store? People with healthy VOR develop “visual dependence”. Our brains become reliant on our vision and visual cues to keep us up-right. However, with the disorder, our need for those cues is magnified. If our field of view is wide open (outside for example), we have few if any proximal visual cues to rely on, so we tend to look to the ground and walk awkwardly. In open space rooms, I tend to hug the wall for example. Our attempt to find those cues becomes overwhelming and if busy patterns (read: rows of soup cans and moving people) and lighting are added to the mix, we start to feel and act super drunk.
If the only thing that was affecting us was VOR then Schubert offers a few treatments, which are worthy of us to consider. Vestibular physiotherapy, medication, and even surgery could help. Changing progressive lenses to sets of single-vision lenses with smaller lens sizes could be helpful to reduce distortion that only adds to our problem. Contact lenses may also work better for you. He also recommends using high-quality sunglasses, practicing focusing on a large object a short distance a way to walk toward, walking sticks for surface cues, eliminating fluorescent lighting in the home, and being aware that patterns in flooring, wallpaper, and window coverings could trigger our ataxic responses. Personally, I have found using my wheelchair in the big stores much more comfortable than attempting to stagger around and developing sensory overload.
Keep in mind that while VOR disorder may help to explain what we see and how we see it, our greater medical contexts of neurological diseases complicate our situations. Understanding that what we experience has a rational explanation helps me, and maybe you, to better cope with and accept our realities.
—Keep living into it!
(Visit vestibular.org for more information and check out Article 82 referred to here.)
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