Q: I wanted you to determine if I would be a candidate for FUE (to camouflage a scar). After reading through your vastly informative website, I had become aware that the Fox test is necessary to determine patient viability for FUE. When I mentioned the test, I believe I heard you say it was unnecessary. Unfortunately, I can’t help but think there was miscommunication between us, as your letter states that I should schedule a Fox test if I am considering FUE. Please confirm if a Fox test is, in fact, necessary. — N.S., Garden City, N.Y.

A: I perform FOX tests on all patients when I am considering a FUE hair transplant. I do not routinely perform FOX tests before repairs (or on eyebrow transplants) where the number of grafts is relatively small.

The purpose of FUE is to identify those patients in whom FUE is inefficient — i.e. there is a greater than average risk of damage during the harvest. If this is the case, I would not perform the hair transplant since even slight inefficiencies create a significant problem when thousands of grafts are transplanted.