Funny story about those scars.
My dad had a to wear glasses,and about 15 years ago he went through a laser surgery,which improved his vision by bit,and left a scar on his left eye,since then,he had a better vision in his right eye,and he still needed to wear glasses.
About four years ago he went to get he went to get new glasses,because his vision got a bit worse,and when he was there,the optometrist asked him "Do you know you got the wrong number on your right eye?", my father didn't know,and then he understood that the bad vision on his right eye wasn't because of the scar,but because of some error the optometrist did.