Here is a two dimensional presentation (figure 1.) of an actual patient’s entire donor area. Each of the 14 boxes represents a region of the donor area and have all been magnified for easier viewing. You may notice that some follicles have been circled in a few of the boxes to simplify the task of counting each follicular unit. Also attached is a depiction of a 2nd patient’s donor area where 1400 CIT grafts were harvested from the entire donor area. By observing figure 1, you may find that hair densities are different from one region to another. Most patients will have an average hair density of about 180 hairs per square centimeter while other patients will have higher densities. The donor area shown as figure 1 has hairs that occur at an above average hair density of 286 hairs per square centimeter. Each box is a quarter of a square centimeter.
At any rate, CIT allows us to take advantage of harvesting specific follicular units to yield the best aesthetic result in the donor and recipient areas. We harvest from within the entire donor area to minimize noticeable decreases in donor density. Harvested donor hair follicles are best extracted where areas of denser hair growth are within the donor area. Dr. Cole has steadily improved on our method of harvesting and has perfected instruments used in harvesting numerous types of donor areas. No two donor areas are the exact same so instruments used during our procedures are constantly changing. Our new method of harvesting has allowed for the average number of hairs per follicular unit to be about 2.9 hairs per graft with a transection rate of about 2%. Transection occurs when follicles are critically injured at the bulb and have zero chance of survival. In a recent study, several strip surgeons completed strip (FUT) procedures with microscopes and without microscopes. In cases where microscopes were not used, 20% of 406 follicles (range 15% to 23%) were transected. However, in cases where microscopes were used, 10.2% of 343 follicles (range 0% to 25%) were transected. It is very important to know the statistics of your potential surgeon beforehand.
The importance of donor density is that it dictates how patients must realistically approach their hair loss. Donor density is a major factor in determining how much donor resource each patient has to combat hair loss. Dr. Cole typically advises younger patients to maximize medical therapy, focus on the frontal scalp and postpone goals of aggressive coverage in the crown. Since hair loss can be a progressive condition, lower density in certain areas allows for our patients to look natural in the event of additional hair loss. Dr. Cole favorably recommends that the conservative approach to hair restoration is in all patients’ best interests as there is no sure-fire way to predict that any patient can resolve hair loss in one procedure. We educate patients of the fact that donor area resource is finite. Our clinic offers to provide consistent quality results with fewer grafts transplanted and less grafts transected.