“It is in the brain that the poppy is red, that the apple is
odorous, that the skylark sings.”
– Oscar Wilde
Well I wrote two political posts in the last couple of days and that, as they say, is enough. Everyone’s mind appears to be made up anyway and so my musings appear to have no useful purpose. So enough politics for now. I do recommend we all get off of our dead asses, acquaint ourselves with the issues and VOTE IN THE MIDTERM ELECTIONS.
Today I want to talk about eyes. Mine in particular.
Those of you who follow me know that 6 years ago I was totally blind for several weeks. It wasn’t fun and you can read about it here:
Blindness can be a curse of long-term diabetics (and mine has been with me virtually all of my life) along with circulatory disease leading to amputations (a cousin died in his forties after losing parts of both legs), heart disease (my mother died from a heart attack at 43) and kidney failure.
And so I take good care of my self and at 75 I am still quite comfortable living on my own. Luckily I survived a heart attack in 1995.
My first eye problems (beside the fact that I have been woefully near-sighted since childhood) were cataracts. In the late ’90s it finally got to the point where they had to be removed,
For you fearful out there, let me tell you it was the easiest thing I have ever done and most rewarding. I had a great eye surgeon who removed the clouds and fitted me with artificial lenses. In the old days you didn’t get fitted lenses; you got eyeglasses the size of coke bottle bottoms. You looked like “daddy cool.”
For the first time in my life I was able to see 20/20 without glasses, though I needed glasses for reading. I reveled in my new eyes and face, sans frames.
Move forward to 2004.
My wife is critically ill and sleeping in a hospital bed in our home. She is scheduled for admittance to hospital the next day to find out what definitively is wrong. I am seriously worried and I was right. She had a metastasized cancer and would pass before the week was out.
That Sunday morning I woke with a splitting headache and noticed something was wrong with my vision to the left. Low sugar levels perhaps? I ate breakfast and took to the couch waiting for the headache t subside.
I was not going to the hospital myself that day. She needed me and I was going to there.
The headache subsided but my left peripheral vision did not return. After she was admitted to hospital and settled in I visited my eye surgeon on Wednesday.
He did a visual scan test. I looked into a scope and red dots flashed in different places one at a time before my eyes. I was to press a button each time I saw one and the results were recorded and a graph noting the location of the flashing dot I saw.
The results were plain to see – no dots were recorded on a large portion of the left side of the graph.
“You had a stroke. You have a left homonymous hemianopsia.”
Besides being hard to say left me try to explain the condition;
A homonymous hemianopsia is the loss of half of the field of view on the same side in both eyes. . It occurs frequently in stroke and traumatic brain injuries due to the way part of the optic nerve fibers from each eye crossover as they pass to the back of the brain. The visual images that we see to the right side travel from both eyes to the left side of the brain, while the visual images we see to the left side in each eye travel to the right side of the brain. Therefore, damage to the right side of the posterior portion of the brain can cause a loss of the left field of view in both eyes. Likewise, damage to the left posterior brain can cause a loss of the right field of vision. The most common causes of this damage include stroke, brain tumor and trauma.
Look at the above colored boxes and picture them as four colored buildings. If you were to stand across the street from them and stare at them dead center a person with a left homonymous hemianopsia would see nothing of the two buildings on the left with either eye. He would have to move his head to see them. Moving his eyes alone wouldn’t help. If I put my nose on the computer screen I can only see the boxes on the right side.
What a person with a complete left homonymous hemianopsia sees out of either eye.
This condition is a result of damage to the right visual centers of the brain and not an eye problem. The eyes are working fine and transmitting but there is no receiver.
Now I do not have a complete hemianopsia. On my left I have lost only perhaps a third of my visual field. My Hemianopsia is in more of a crescent moon shape or perhaps shaped like the horn of Africa starting in Egypt, moving south and jutting out in the lower left quadrant before moving back.
I am lucky. I still have two thirds of my left visual field; it could have been much worse.
Of course those suffering a massive stroke will have many other problems in addition to a possible hemianopsia. Here again I was lucky. My stroke affected only that left portion of my visual field and even there only partially.
The “view” pictures above really can’t do justice to what a hemianoptic sees.
First of all it tries to illustrate what a complete loss of visual field on the left looks like. I luckily still have maybe 2/3s of that left visual field, but not an even line. Horn of Africa as described,
Secondly we do not see black. I saw blind black in my life time and that is not what I see now.
Do you remember the early television days and static?
This is what I see in my blind crescent/horn of Africa area. It will take on the colors of whatever I happen to be looking at. If for example I am staring at my green lawn, my brain will “color in” the static with the background colors so that I perceive green static. If I close my eyes in the dark I can still perceive the black static next to the velvet quiet black of closed eyes.
I had an MRI after the visit to the ophthalmologist and indeed had suffered a blood blockage to the right occipital lobe – the “receiver” of all eye images on the left of midline. Just a tiny little thing, but enough to take away a third of my visual field.
It took some getting used to; before I “learned” to scan to my left I was constantly bumping into things. Visiting my wife I has hit by an elevator door closing from my now blind left side. After a time I got used to it and how I function with a visual limitation.
For a number of years I wore glasses fitted with prisms on the left hand side of each lens. Since the remainder of my vision was still good, the glasses were primarily to hold the prisms. With these glasses I could see what was on my left without moving my head – only my eyes. Looking through the prisms would bring whatever was on my left into my field of vision.
Getting used to prisms requires some work. Looking through the prism I could see what was on my left in my remaining field of vision. For example if my glass of scotch was on my left I could glance through the prism and see it without turning my head. The problem is that the glass of scotch is not physically where your vision tells you it is. Look at it, reach for it and you will find it is not there – it is to your left. The image is moved to the right by the prism so you can see it but it is not where your brain tells you it is.
I got used to them but at my youngest daughter’s wedding I put them down and then lost them. By now however I was so used to functioning that I found I no longer needed them. Today I wear ordinary glasses.
I no longer read books as I need to scan the pages and often lose my place when moving to the next line. I have solved that problem with a Kindle where all the text is within my field of vision.
Crowds can be an issue and bumping into people. Airports are the worst. Walking to my gate there will be people moving in the opposite direction on my left as well as those in a hurry passing on either side dragging their carry-ons. So I’m careful in crowds.
Other than that I don’t think much about it anymore save how lucky I was. Brains can be remarkably resilient.