I have a Seborrhoeic keratosis on my cheek. I got retin-a .1% from my dermatologist. My keratosis is almost flat now but not quite flush with the rest of my face. The keratosis is very, very slightly raised -- just above a hairline from the rest of my face. Also,I have some scaring around the keratosis. I think these scars were caused by the retin-a. I'm not using the retin-a any more. Will microdermabrasion get rid of the remaining keratosis and the scarring? If not, what are my alternatives?