Hair loss is undeniably linked to a genetic programming. Hair from the upper part of the scalp is often scheduled to shrink over time and, in some cases, to disappear. Hair from the upper part and the sides is almost always resistant hair that will remain the entire life. The theoretical principle is quite simple: micro grafts consist in transferring this resistant hair from the back of the scalp to the bald front area. Furthermore, you should collect the graft as it stands. That is what is called a follicular unit transplant.
The follicle is an entity that contains two, three or four hairs, rarely one. All the techniques other than the follicular unit transplant consist in transferring several follicles, or pieces of follicles, in a single slit and lead to a pluggy or a leek field aspect.
In 1994 and 1995, two articles written by B. Limer, B. Bernstein and W. Rassman showed the interest of isolating each follicle. Hair transplant was born.
FUE and FUT are the two follicular techniques we use nowadays.
The goal of a hair transplant is to introduce the maximum amount of hairs in the tiniest possible volume. The careful cutting using a microscope enables us to remove all the skin and fat in the follicle and also to remove the conjunctive tissue found between the follicles.
This enables us to implant a higher number of hair in a delimited area. Depending on graft thickness, which is determined by the number of hairs that a graft contains, we will be able to transplant 35 to 45 grafts for every cm², which means 45 to 80 hairs per cm².
During the cutting phase, the grafts are classified according to the number of hair they contain.
There are 3 types:
- the "singles" group, which contain one hair. These grafts are placed in the first rows of the front hair line.
- the "doubles" group. These grafts are placed just behind the "singles".
- the " three, four or more hair" group. These grafts are exclusively placed inside the recipient area.
This judicious use of grafts is the only technique resulting in a totally natural aspect.
Several comparisons were made regarding growth levels depending on the different cutting techniques applied. Nowadays, the use of microscopes allows us to avoid any type of waste. The percentage of growing hair varies from 95% to 98% when prepared under a microscope.
Cutting hair using magnifying lenses or without any visual aids at all rarely yields a good result. The best way to illustrate this is with the cutting of grafts containing white hair.
Actually, the root of these hairs is transparent and it is totally impossible to see them without using a microscope! Without the aid of a microscope, the degree of transection will inevitably rise, resulting in a waste of hair.
The number of transferable grafts is somewhere between 6,000 and 10,000. Any loss is dramatic, because it is disappointing for the patient. Moreover, the hair loss undermines the success of future grafts, as it exhausts the donor zone unnecessarily.
Incisions are tiny and precise. It is thus also possible to treat areas which are not completely bald yet.
You can have a hair transplant at any time. These days you no longer need to be fully bald to have one.
When incisions are made with sharp instruments, the scar goes undetected.
However, when blunt instruments – which damage tissue – are used or when punches are used to make the incisions, you will notice tiny ugly scars at the root of each graft.
Transferring hair actually impoverishes the donor area in order to enrich the recipient area. How can it work?
The basic principle which hair transplant is based on is the notion of visual apparent density, which is discussed in another chapter. As said, it is possible to reduce an original density by half with no visible signs. This principle is used both in the donor and in the recipient areas. That is how we can reduce the density of the donor area while increasing that of the recipient area. The number of hairs doe not change: they do not multiply, they are just moved to another place.
This is very important to try defining the outlines of the future hair loss, especially when the patient is young.
Indeed, the grafted hair will remain during the whole patient’s life. We must then not only imagine the immediate consequences of the transplant, but also the mid-term and long-term ones. A hair transplant should ideally be the last one, that is to say that it should be sufficient. In practice, this means that the patient should ideally lose all his hair he still has to lose, keep the grafted hair only and still be in a situation which seems natural.
This is not always possible. For example, when a young patient wants a transplant for the temples, he must know that he is very likely going to need a second surgery in the future.
Given these two principles, we have to be very careful while defining the surface to cover and the density to reach. This is not about reaching the maximal density, but reaching an ideal balance between density and covered surface.
Moreover, this is often wiser to base the strategy on the number of grafts that can be reached on short- and long-term. The frequent questions “How many grafts do I need?” can often be more judiciously replaced by the question “What is the number of available grafts?”. Furthermore, we should have a notion of the total number of available grafts both on the short and on the long haul.