Surgical hair restoration is more popular today than at any time in history. This is due in part to the advent of follicular unit extraction (FUE). This procedure has a lower cost of entry into the industry for new doctors thus more clinics are opening every day. This logically makes the procedure available to more people worldwide. For all of the improvements we see in the industry there is still one thing that cannot be accomplished; full hair restoration
To clarify, full hair restoration means different things to different people but for the sake of this article we will assume that full hair restoration refers to a complete restoration of coverage and density from the front of the scalp to the back of the scalp. We will reference more aggressive cases of hair loss on the Norwood Hamilton hair loss chart as NW5, NW6 and NW7 degrees of loss.
The single rule of hair restoration that dictates the success or failure of every hair transplant surgery is “supply and demand”. The patient’s donor area is the supply and the area of loss is the demand. If a patient has a small area of loss then it is logical to assume that a full reconstruction can be achieved. In some cases, depending on specifics, this is true. With regards to more aggressive cases it is mathematically impossible.
On a typical NW5 patient the amount of hair loss that has been experienced is roughly 50%. Half of all the hair on the patient’s scalp is gone. When you consider the safe donor zone only covers a portion of the back and sides of the scalp we are dealing with an overwhelming degree of demand for an underwhelming degree of supply. The challenge is to identify and prioritize the areas that the patient cares about most and in almost every case that area is the front. This includes the hairline, mid-scalp and to the vertex. On a NW5 the vertex still exists albeit in a lower than native density so fewer grafts can be used in this area for the sake of blending. The crown on a NW5 is prohibitively large to expect a similar degree of coverage but cosmetically appealing thin coverage can still be achieved. A patient with NW5 hair loss will need 5000 to 7000 grafts for a cosmetically acceptable result.
A patient with NW6 level hair loss obviously has a demand for higher numbers of grafts and a potentially smaller area to harvest from. The need for more hair beyond that of a NW5 lies in the lack of a vertex and an expanded crown region. NW6 patients can experience strong frontal reconstruction but they should expect even less coverage for a crown but they can still achieve a cosmetic improvement if expectations are realistic. Depending on characteristics a patient will need in the range of 6500 to 8500 grafts to achieve a cosmetically acceptable result.
Patients with NW7 stage hair loss are usually discouraged from having surgical hair restoration of any kind. The total area of demand outweighs the available supply by such a vast margin that it is many times considered to be a useless, expensive and even cosmetically detrimental endeavor regardless of the amount of care that is taken for the best result possible. Cases of NW7 loss should be HIGHLY scrutinized especially for the patient’s overall final expectations of the result. There are many cases of NW6 and NW7 patients receiving little to no surgical attention in the crown region and still having a natural and cosmetically improved appearance but these cases are the exception especially as we move higher on the hair loss chart. Regardless, NW7 patients can achieve a level of satisfaction from surgical hair restoration as long as their expectations are low and they have favorable surgical characteristics. A NW7 patient will typically need 7,000 to 12,000 grafts to achieve a cosmetically acceptable result.
Many clinics that have been proponents of FUSS and subsequently embraced FUE have taken the position that a combination approach is the best method of achieving the ultimate number of grafts for any given case. The idea is that a patient should “strip out” using follicular unit strip surgery until it is agreed that the donor area can no longer provide additional strips without compromising the donor laxity resulting in a stretched or widening donor scar. This is where it is argued that FUE can take over to continue with more surgery to harvest additional grafts above and beyond what can be provided by FUSS alone. The logic is that the laxity is no longer a factor and viable donor hair can be extracted from outside of the traditional safe donor zone while still retaining non-DHT sensitive characteristics. Unfortunately, even with this approach, the FUE surgeon must take into account the one to one ration of reduced density throughout the donor zone. If this density is reduced too much then the cosmetic viability can be compromised thereby revealing the donor scar from the previous FUSS procedures. Regardless, combining the two procedures does allow for greater numbers of grafts to be harvested thus a satisfying outcome is more likely.
With patients lower on the Norwood chart the appearance of a “full restoration” is more likely with proper planning and care but it should always be remembered that a true full head of hair is not likely to be reproduced as each hair lost would have to be replaced. This is a mathematical impossibility if there is any expectation of achieving naturalness without the appearance of surgical intervention.