Hattingen HT : Coverage Not At The Expense of Density

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Hattingen HT : Coverage Not At The Expense of Density

A hair transplant cannot fully replace hair lost in a 1:1 ratio (100% restoration); a hair transplant therefore strives to achieve an illusion of thickness, placing the FU´s (grafts) in such a way to cover a surface area that in reality used to have much more hair. This basic principle allows especially people with more aggressive hair loss patterns to be able to achieve if not total but almost total coverage with a natural looking thickness or density.

The Visual Appearance of Hair Loss:

Hair Loss becomes apparent when light penetrates the hair coverage and is reflected back off the scalp surface. Our eyes can only make sense of something if there is light, if it is pitch black; there is nothing for the eye to see. So, when there is enough density the light only reflects off the hair coverage and not the scalp, therefore blocking the appearance of light and the appearance of hair loss/thinning.

Miniaturisation

The MPB hair loss process is not a sudden occurrence, but rather a prolonged process of miniaturisation, where the hair life progressively shortens its growth phase, the hair shaft becomes thinner, does not grow as long or as fast. The loss of diameter of the hair shaft leads to a loss in the coverage potential of the hair; this in turn allows light rays to reach the skin surface. The reflection that bounces back into our eyes is more and more from the skin. We see this as thinning hair or hair loss.

The goal of a hair transplant is to redistribute a sufficient amount of healthy, permanent hair from the donor area to the area of hair loss, recipient area in order to block the reflection of light off the scalp and therefore to attain the appearance of fullness.

Simply put, to try to cast a substantial shadow on the skin in order to block the light rays.

Consider the fact that your donor density on the back of your head (occipital area) is usually around 80 FU’s/cm², whereas the density on the lateral sides is around 65-70 FU’s/cm². This difference of 10-15% less density is imperceptible to the naked eye. This is proof that sufficient coverage of the skin / blocking of light rays is achievable with less than 100% of the mathematical density.
There is therefore a difference between mathematical and aesthetic density, and this is a vital aspect that makes a hair transplant work.

Coverage but not at the expense of density

The question then is how much hair has to be redistributed in order to achieve the blocking of light and an aesthetically acceptable coverage?
This depends on the individual´s characteristics or quality of the hair (thickness of the hair shaft, curl, colour contrast between hair and skin), but also the length of the hair shaft and the way the hair is combed /styled.

It is important to understand that the hair needs to have a certain length in order to be able to develop its coverage potential. The shorter the hair is cut then less shadowing/ coverage or fullness is achieved so for most people it is important to allow the hair to grow long enough to overlap the surrounding hair and therefore enjoy the maximum result of the transplanted hair.

Besides the above mentioned factors that are not influenced by the operating team, there are some technical tricks that we can use to maximise the coverage potential of transplanted hair. A more acute angle of the recipient incision allows the hair to lay flatter onto the skin, therefore obtaining a longer shadow. The method and technique of slit making, orientation and the use of custom blades allows for greater angulation control, recreates a naturally arranged pattern of FU’s and ultimately lead to better coverage/ better illusion of density.

Hair characteristics, correct placement angle and orientation are commonly discussed to be important to gain the illusion of thickness and greater coverage.
We touched on this in another thread; one aspect that is rarely discussed if at all is the use of the natural curvature of the hair to gain maximum coverage from each hair, and allowing the hair to blend into the native hair more effectively, so even with a shorter cut the curvature does not contradict the surrounding hair.

Image

This shows the FU´s after being removed and the natural curvature, below shows when placed in the recipient 2 FU´s with opposing curvature placement, one up the other laying down.

Image

Even a straight hair has a curvature, the lay of the hair when it is held up or when in the scalp will always fall in a certain direction when it exits (usually with the curvature of the hair facing down, towards the scalp). When placing a hair in the recipient site the hair shaft of the graft requires a few mm´s in order for the technician/placer to be able to determine the correct direction of the curvature. This is pain staking work and nothing to do with the way the recipient site (direction /angle) has been made, it is solely down to the technician checking each placement as it is made and adjusting accordingly which way the hair curvature falls.


To have enough hair length visible on the FU graft in order to correctly asses the direction of the curvature means that the hair cannot be close shaved in the donor when harvested. This proves problematic with FUE as the donor needs to be close shaved in order to precisely extract; it is easier with FUT as the donor area hair can be left longer.

Placing the hair with the correct curvature to the surrounding hair has three major benefits, firstly it will blend with the surrounding hair and not give the appearance of misdirected hairs, secondly it will allow each hair to give greater coverage allowing for fewer grafts to be used over a specific area of the recipient and thirdly more fullness or density can be achieved as the hairs are laying in a uniform pattern.

Hair transplants are a unique blend of strategic vision, understanding of mathematical and physical facts, technical prowess and artistic feel.

The redistribution of hair principle and the skills of the clinic to maximise them are the key secrets behind a successful hair transplant.

What is an adequate amount of hair that can be removed safely from the donor area to achieve an aesthetically pleasing coverage and density?

With a finite donor supply how is this possible?

How could hair loss evolve over time?

These are strategic considerations to be taken into account before deciding to undergo a hair transplant. The individual’s hair characteristics, their goals and expectations will ultimately be dictated by the resources of the donor hair and the artistic and medical ability to ensure that the supply can reach the demand dictated by the surface area of the recipient area; and if not the goals and expectations will have to change. For this reason it is important to keep an honest dialogue between patient and clinic to ensure your goals can be met.

Angle and Orientation

As said earlier the FU´s are placed in such a fashion, at specific angles, direction and positioning in relation to each other in order to obtain a nearly identical natural appearance. The angle and direction of each incision must be as precise as the appearance of the natural hair.

In the front areas for example, the angle should be acute, this helps to increase the coverage given by each hair unit with each unit overlapping the other, a “tile effect”.

The "crown" is a good example how the distribution of grafts can give the illusion of fullness without destroying the donor area as the crown can require many more grafts that treating a similar size surface in the frontal due to the spiral effect of the crown, less over lapping of each hair and changes in angle and direction.

Thickness of the Hair Shaft, Hair Calibre and Natural Groupings

Very basically the thicker the diameter of the hair shaft the more surface area it will cover, fine wispy hair requires more physical hair to cover the same area and to achieve the look of fullness.

Natural hair groups, single units to 3 and 4 hair units, this is different to density; density is the number of natural units you have, calculated per cm², but does not take into consideration the number of hairs in the same area. Typical the sides of the donor have a lower density and hair count compared to the back where there typically a high actual density and also hair count.

As an example it is possibly to have a high density per cm², 80 FU cm², but a low hair count if the majority of units are made of single and 2 hairs, this could mean only 120 actual hairs, compared to the same density but a balance of natural hair units resulting in 176 actual hairs.

If this is multiplied over a procedure of 3000 grafts the effect is dramatic in terms of the amount of coverage that can be achieved, short and long term, and possibly render them a non-suitable hair transplant candidate, dependent their hair loss stage and potential for future loss.

Colour Contrast

The greater the colour contrast between the hair colour and scalp pigmentation the higher the perceived colour contrast is. With greater contrast it is harder to block the reflection of light whereas with a low contrast the scalp is less noticeable and easier to conceal, allowing for a greater coverage with fewer grafts required.

Hair Length in the Recipient

Having a very short/shaved hair style after a hair transplant is not something that is possibly for the vast majority of hair transplant candidates.
The object of a hair transplant in the recipient area is to give coverage over the scalp and the illusion of thickness or a good head of hair. To achieve this hair has to be kept at a certain minimum length or longer so each hair covers, or lies over the surrounding hair. This has the effect of creating layers of hair that block light from reflecting off the scalp, the more the light is blocked the greater the illusion of density.

The shorter the hair, and if shaved all illusion of density is taken away and as it is impossible to replace like for like hair as before hair loss the result can appear unnaturally thin.

The thought of very short or shaved hairstyles should be viewed with a little caution as there are very few people who have the donor hair capacity and excellent hair characteristics to achieve this type of look from a hair transplant, especially higher NW patterns.

A hair transplant basic premise is to cover a bare scalp with hair by a reasonable compromise between graft density and hair characteristics. Therefore it makes aesthetic sense to allow the transplanted hair to grow a little to increase the look of fullness.

_______________________________
Hattingen Hair Transplantation

http://www.hattingenhair.com/index_en.html

https://www.youtube.com/user/HattingenHair1
contact: [email protected]

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Je ne suis pas docteur, mes avis ne sont pas des recommandations médicales.
I'm not a doctor, my opinions shouldn't be regarded as medical recommendations.
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