Update on vision therapy: I have been working around the clock to rehabilitate what is for me quite a debilitating oculomotor dysfunction. Once I work out completely what is effective, I plan on writing a lengthy post about it on my blog. For now, I continue to research in order to get to the bottom of things. I have made leaps and bounds in identifying the specifics of my condition, there is so little literature out there in respect to what physiotherapy is required for my symptoms. I have now come across other cerebellar stroke survivors with the same symptoms as myself, and know that there is a wider community of stroke survivors who would benefit from my research. So, here goes, this is an update on what I have uncovered, and the exercises I am doing to correct the condition known as cerebellar stroke syndrome. As a caveat, I am no medical expert but am stabbing in the dark like everyone else, and I could be barking up the wrong tree. However, I can know what has been working for me, and hope I’m on the right track. My understanding stems purely from cerebellar stroke, other stroke may have different causes for visual and balance problems.
At first I thought I had a proprioceptive impairment, which generally speaking is true, but it goes much more deeper than that and is far more complex. I worked out I have an oculomotor dysfunction, which also is true but, as above, goes much more deeper than that, and is far more complex. I will try not to make this too technical, as there is a lot more to this condition than my summary in brief.
The issue lies in what they call the vestibulo-ocular system, this system is a very complex visual-balance and coordination reflex affected when the cerebellum is damaged. It’s complex because it requires so many functions in order to do the most simplest of tasks.
For instance, sitting on the side of the bed and putting on a pair of socks may seem like an effortless activity but the eyes must operate vertically and horizontally, they must track the hand to the socks, they must adjust to the lighting, all the while the body must balance upright, the socks must be coordinated onto the feet, the eyes will track the feet entry into the socks (perhaps noticing other things in the space while doing the task), the body must balance while the leg is lifted, all the while the eyes are adjusting focus from the feet being on the floor to being lifted, as well as the foreground movement of the hand with the socks. When you think about it, the brain must account for accuracy, it has to factor in any latency, it must follow multiple trajectories, and time speed and acceleration of saccades (eye movements) in order to coordinate a movement.
Normally, the cerebellum makes sense of all this movement and sight. It will organise visual noise so that the eyes can focus only on what it needs to focus on. It will calibrate movement of the body and the eyes so that this function can be plain sailing. This region is called the vestibulocerebellum. When there is damage, the cerebellum can’t do this without difficulty. Usually, the eyes and the vestibular system are working perfectly, it’s the cerebellum that isn’t able to synchronise.
Okay, take a breather, there’s more. Nystagmus and blurred vision are two symptoms that can be a result of brain injury. Medical professionals don’t really know why nystagmus occurs but it does, even without brain injury. There are different sorts of nystagmus which makes it difficult to assess just what issues may result unless one has a thorough eye test (via the Optometry Department at the hospital)
So, this is why giddiness occurs. I make the distinction between giddiness and dizziness. For me, dizziness is the room spinning and relates to vertigo. Giddiness is a sensation of whirling that comes from within the body. Initially, I was given ‘gaze stabilisation’ exercises to do but this kind of exercise benefits vertigo, and in my experience, not giddiness. I then moved to doing eye exercises like pencil push-ups &c. While these are good, because they concentrate on focal points, they are limited as they only pay attention to oculomotor functions. I then moved onto ‘visual tracking exercises’ which are also beneficial but are passive, i.e. there is no movement of the body involved. So, recently I have begun what they call auditory biofeedback in combination with movement, visual and focal tracking.
Auditory biofeedback is a way of commandeering the body through an outward-looking voice, essentially talking to oneself. It’s been proven to ease nystagmus, and so I have adopted it as part of my exercise routine. I will write more about the practical side of this at another time, save to say, I have identified that the up/down movement of my head is causing the most giddiness. Every person will be different, and I will write something clearer as to what I have been doing to improve my situation. Logically, this impairment can improve naturally, as we have to move and see in our every day activities, but the benefit of controlled exercises enables the brain to work on one problem at a time, resolve it, and then move onto the next. The natural rectification of this would take a long time if left to its own devices because every millisecond of the day, movement and sight changes, and it means the brain doesn’t get time to use repetition in order to put into place a result. This is why impairments can drag on for many, many years as opposed to a few years. As I mentioned at the start, everyone is different, so an individual’s circumstance may prolong something even if controlled exercises are applied.