Bikes with good blind spot visibility

I was wondering if something as simple as an extra mirror would work.

Bar end?

Attached to the existing mirror stem somehow?

The National Association for Bikers with a Disability may have previously helped with similar issues.

I have had two detached retinas. My first one was quite bad as I ignored the symptoms and was told i would lose most of my sight in that eye.

After my second one (other eye) I had a cataract operation in each eye and the difference in the first eye was incredible. A cataract develops as a result of the surgery and it happens really quickly so it may be that which is affecting the vision. See if you can get the cataract dealt with, you might be surprised.

I sold my bike after my first retinal detachment but got a bike again after my cataracts were fixed. Had to notify the DVLA but they are happy with my vision I think it is the missing segment of vision that is the biggest issue.