Ear mite infection

Question
A neighbor's cat had a severely swollen ear and they weren't taking him to the vet due to the expense. I took him in and found out he had terrible ear mites.  The vet slit his ear twice and drained it, but it's swollen again.  They treated the earmites but the swelling keeps coming back.  We've had him on antibiotics twice a day but it's been two weeks and the vet says he needs to be anesthetized and have the ear thoroughly drained and cleaned out, which will involve stitches and quite an expense.  What will happen if we leave the ear as it is and don't do the surgery?  Is he in pain from this?

Answer
This is called an aural hematoma and if the cat's ears are treated properly, the hematoma only needs to be fixed once.  If it is not fixed, the ear cartilage crinkles and it can close off the ear canal.  That would be painful because stuff collects in the ears and that stuff cannot get out, so it builds up pressure.