FUE (Follicular Unit Extraction)
FUE also known as “Follicular Unit Extraction” is the movement of genetic groups of hair known as follicular units (FU); “bunches” of hair usually 1 to 4 hairs. A surgical punch surrounds the FU and with a great deal of skill and precise measurement of skin and hair angles the FU is removed. Extraction is relatively slow compared to the Strip Technique with between 1500 and 2000 being extracted and placed in one day. More important to the amount is the yield or growth rate, so the amount will vary from person to person.
Dr Villares believes the FUE Technique has proved a good option for those with minimal thinning and those who have undergone multiple “older” procedures and their donor is impaired, as FUE opens the extraction area allowing hair to be removed in areas a Strip procedure could not. Larger areas of thinning say NW4 and higher can be treated with FUE but the person has to have better than average donor hair density and good hair characteristics to ensure sufficient FU numbers can be safely extracted and leave options for the future.
Since FUE became available, various punch sizes have been used and generally the punch size has reduced. Dr Bisanga has been at the forefront of FUE development for a number of years and with his experience prefers to use of a punch less than 1mm; with a 0.75 or .8mm tool he has proved a 4 hair FU can be removed whilst minimising skin trauma, peripheral damage to surrounding FU and control any scarring to the smallest size possible, and in many cases non visible to the eye, whilst maintaining the yield.
To perform FUE to the highest standard the donor area requires total shaving, except possibly for small procedures such as 100-500 grafts when smaller areas could be shaved and hidden by surrounding hair. Shaving will allowing the doctor to precisely measure the angle the FU exits the scalp as well as give a greater comprehension to the position within the skin, a very important aspect of the extraction. If the concept of FU angulations, skin variations and healing is not understood by the doctor, the FU will not be removed intact or will result in a high transection rate or low yield, either way this is bad for the patient. Removing the FU over the widest surface possible will reduce and diffuse the lost hair.
FUE when performed correctly and on a suitable candidate can yield excellent growth and design without causing obvious signs of a hair transplant. It has opened up the possibility to revise and correct old strip scars by placing hair back into the scar opposed to reopening an earlier scar; it has enabled the removal of FU out of the strip safety zone thus enhancing the number of FU that can be taken after multiple Strip procedures, as well as not having to cause a linear scar for those who wish to keep their hair short and only need minimal work. It has enabled the doctor to “cherry pick” certain hair calibre for specific areas of placement; this is very pertinent when designing a hair line, temple points and laterals as well as eyebrow or eye lash reconstruction. The hair ideally needs to be fine and having the entire donor safety zone to choose from enhances the result in such a crucial area. It does have limitations as does Strip/FUT but if the patient is educated and made aware of the pros and cons then FUE has proven in the right hands to provide natural results.
FUE Donor Calculation to Estimate Follicular Unit Extraction Capability
Donor surface area X donor density (less miniaturisation) = TOTAL FU X EXTRACTION % Example: 180 CM2 X 80 = 14,400 FU X 27% = 3888 FU TOTAL CAN BE EXTRACTED
Although the FU’s are removed over a wider surface area compared to Strip/FUT does not essentially imply there are more FU’s to take. To calculate the number of FU that can be removed the donor safety zone is sectioned in to three areas, both sides and the back and measured. The density of FU’s measured in each area and an average taken including the number of hairs per FU excluding miniaturisation.
Overharvesting of the Donor
There has to be a protocol as to the % of FU that can be removed the donor before the area becomes visibly thinner. If this is not managed correctly it will reduce the options of the patient to keep their hair short OR and importantly restrict the donor for future procedures if and when required; this is called over harvesting. Dr Bisanga practices approximately 25-30% extraction per cm2 dependent on hair density and characteristics; he believes in preserving the donor to the maximum whilst making FUE a viable alternative. Obviously this calculation (25-30%) is assuming the maximum amount would be removed in one procedure which is very unlikely and ill-advised. Larger hair less areas or wider scarring can also occur when larger punches are used; this is due to severing adjacent FU’s and causing transection with the likely conclusion of killing a hair. To remove a single FU becomes harder the larger the punch used due to the probability of overlapping adjacent FU; therefore much harder to adhere to the extraction protocol whilst removing enough hair.
Included in this problem is the pattern of extraction, a person’s hair characteristics will determine the pattern of extraction. As the average numbers of hairs per FU can alter dependent on the area of the donor safety zone it is important to keep an educated extraction pattern to not remove too many of a particular size from a particular area. Not taking adjacent or corresponding FU’s parallel to each other, especially larger hair FU groups to ensure no large hair less areas are created. The term “cherry picking” is often used with FUE to remove finer hair for hair line work, but again this has to be controlled to not remove too many from an area, say by the ear and leave the patient with visibly thinner density.
Hair characteristics and FU constitution can play a large part in how suitable FUE can be; it is misunderstood that FUE is suitable for all hair loss stages and hair types and some may not have the right attributes to ensure a solid result. This can be due to reasons such as donor hair density or hair diameter, including the % of miniaturisation in the donor or the average size of a person’s natural groupings of hair as well as skin texture and healing properties. If there is a doubt when consulting on line then a personal consultation would always be the best option before making your decision.