Brief Answer:
This can be because of transient ischemic attack.

Detailed Answer:
Hello
Welcome to Health care magic

I am Dr Dadapeer k an ophthalmologist and I answer health problems related to eye.
I reviewed your history.
It seems from the history that your husband is having sudden onset of inability to focus for long distance.
These symptoms can be because of transient ischemic attack.
The common causes are hypotension, hypoglycaemia, hypovolemia...

Hence we need to look for deceased blood pressure, decreased sugars....

Hence I advice you to consult your family physician for evaluation.


Hope I have answered your question and the information is helpful to you.
Do write back to me for further questions.

Thank you
With regards

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