Brief Answer:
Corneal transplantation will not help your dad.

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 father has got decreased vision/loss of vision because of diabetic retinopathy.
Diabetic retinopathy causes irreversible loss of vision if not treated earlier and diabetes is controlled.
It is unfortunate that your dad has reached this advanced stage of diabetic retinopathy.

Corneal transplantation can cure blindness caused by corneal diseases like corneal opacity, corneal dystrophies, corneal degenerations.....
This will not be of help in your dad case as his retina is damaged by diabetic retinopathy.

As of now there is no reversible treatment for this condition.
The only hope will be use of low visual aids.

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

Thank you

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Brief Answer:
Low visual aids are optical appliances which improve vision.

Detailed Answer:
Hello
Thank you for the follow up question.

Low visual aids are optical appliances which are given to people with poor vision to enhance their vision.
For prescription of low visual aids you need to consult your ophthalmologist.

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

Thank you

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