Hi. I'm online and happy to answer your question today.
The loss of vision on the left side of his visual field is due to damage of the optic radiations in his brain. That may improve a little bit over the course of 6 months or so, but what he is left with after that will most likely be permanent.
The difficulty focusing may be due to nerve damage to the muscle that is used to focus, or it could be related to the visual field defects.
If it is a problem related to the muscle that helps him focus on near objects simple over the counter reading glasses may help. I would try +1.50 power first.
You may, however, want to take him to an ophthalmologist given his history for a more complete evaluation rather then just trying reading glasses on your own.
Does this make sense to you?
I guess you have stepped away from your computer.
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