The skin biopsy is over in 5 seconds. A small patch or plug of skin is taken above the ankle after a spray of lidocaine. A band-aid and you are good to go. The analysis in a special lab (mine went to a Texas) determines the percentage of small nerve fibers in a defined area of the sample. The report will tell you your actual percentage and the desired percentage range. Just for reference, my sample was .09% The desired range was over 8.5%. Quite a difference and an important step in the diagnostic process and in the selection of a treatment program.