Saturday, April 24, 2010

Body Hair Transplant (BHT)




There are about one hundred thousand hairs on the normal human head and about 1 million hairs of the body. Person having major loss of class 7 (almost 75000 hair out of 100000 are lost) may not have enough donor hairs at the back and side of the head (only 12500 out of remaining 25000 may be transplanted). Often donor hair may be even less. This situation made some surgeons to look for other Body hairs. Dr. Woods , Dr. Cole, Dr. Poswal and Dr Umar may be the torchbearers. Body Hair Transplant (BHT) as a major plus point may become donor hair because they are not genetically DHT susceptible hairs as some of the scalp hairs in MPB. But there are many issues with the effective use of BHT as routine. The conventionally used donor hairs from the back and sides of the scalp are very much similar to the hairs to be replaced in MPB but the characters of the BH has many variations such as thickness, length, colour, texture, the growth period etc. As a result for many years BHT was given the back seat. But some studies have shown that BHT hairs may change some of the character if not fully but partially when transplanted to the scalp (recipient "co-dominance" - or partial donor dominance) and this generated more interest and BHT is now being seen more seriously. . BHT is not widely practiced because, it requires special instruments, is very time consuming and the results can be somewhat unpredictable. Results are typically not at par with scalp hair yields Many patients consider body hair unnecessary and try to remove it. A body hair transplant serves a dual purpose by moving unwanted body hairs to the scalp, where they are more productive.


Body hairs from various areas have been used:
Dry zone: Beard, chest, back, limbs, abdomen
Wet zone or Apocrine zone : armpits and pubic hairs (so called because of Apocrine nature of sweat glands- In the case of sweat produced by the apocrine glands, which are located near hair follicles on the scalp, underarms, and groin area, the sweat contains fatty compounds. Bacteria feed on this sweat when it is secreted to the skin´s surface, and the resulting waste products, fatty acids, ammonia, and chemical reactions form a palpable odor which is unique for every individual.


 

Possible Uses of BHT:
1.      Obviously the most common use of BHT is as a viable option for those whose traditional donor hair supply is depleted.
2.      To feather out hair line by cherry picked thin and soft body hairs esp. in the people with strong and coarse scalp hairs where taking the thin hairs from the nape of the neck or per auricular area may not be a good option because they do not belong to what is conventionally called safe donor zone of scalp.
3.      To camouflage the widened strip scars of already depleted donor area where taking further the hairs from the scalp either by strip or FUE is not a sensible option. Coarse Beard hairs and other BHT from Apocrine area which grow thick and long is a good option.
4.      Body hair is an excellent filler to increase the density for use in between naturally thinning hair
5.      Transplanted scalp hair for the eyebrow restoration may not be the best match and grow very fast and need to be trimmed often. Some body hair with better match ( lighter colour, thinner diameter and slow growth than that of scalp hairs).
6.      Body hairs may be used for restoration of the hairless scar etc which become more obvious in the exposed part of the body.
7.      Donor recharging or Donor sealing of the scalp donor area by BHT esp. when the scalp donor area is very thin.

Problems:
·        Tiny Hyper or hypopigmented marks may be visible in some
·        Follicluitis esp. in case of buried or transected follicles with ingrown hairs may sometimes need antibiotics or steroid to resolve.
·        Keloid esp. is possible in the chest and shoulder area- one may doe a small test grafting
·        Redness for few weeks may be possible avoid sun exposure and use steroid application
·        Unpredictable growth at times
·        Long time to grow at times after transplant
·        Synchronous cycles
·        Due to difficulty in extraction compared to scalp hair may be more expensive and time consuming ( slow extraction and less yield per day) due to difficult positioning of doctor and patient.

It is a general perception that the short hair style gives the less ugly feeling of baldness than when the side and back hairs are kept long. Also, keeping the hair shorter might cut down on the number of grafts needed to diminish the bald look. BH usually do not grow very long (1 to 2 inches or less because their hair cycle is short) since it will not grow as long as scalp hair, a shorter hair style should ultimately be preferred.


Technical issues for BHT:

1.      The acuity of direction makes it demanding to use the instruments with more precision
2.       Most BH do not have as close a Bony support to the skin as that to the scalp hair (except in case of sternum and shin of tibia etc.). Some firm background support makes it easier to extract the grafts and in case of pubic and abdominal area due to minimal firm support at the back ground may make extraction more challenging.
3.      Many body hairs are not robust and without the good bony background it may nor be easy to harvest such hairs in some areas esp. when they are acutely placed and every other hair grows in different direction. This makes the extraction process very slow.

4.      At a  given time 80 to 90% of scalp hair are in anagen ( growing phase) and only about 40 to 60% of Body hair  are in anagen phase Some studies show that body hair has a very short anagen phase and a very long telogen phase.
Their duration of anagen is much shorter (12 to 16 weeks) as compared to the scalp donor hair (2 to 5 years).This means that body hair grows in a period of about six months to about 2 inch long, and they then rest on this length for some years. In Body Hair Transplantation when hair is transferred from the body to the scalp, it may have considerable delay in growth due to their long telogen phase. That does not mean that 10% to 20% of head hair and 40 to 60% of body hair died. It means that those percentages should always be resting or in telogen. As one hair cycles out, another cycles in and begins to grow. since body hair growth cycles are faster and more hairs are resting at any given time, it takes more body hair ( and even more BH follicular unit grafts- because most grafts have only one hair unlike the scalp grafts which may have up to 4 hairs) than scalp hair to create the same illusion of density. In Body Hair Transplantation when hair is transferred from the body to the scalp, it may have considerable delay in growth due to their long telogen phase.
5.      The dermal components of the hair, secondary germ cell and the dermal papilla are attenuated in telogen hairs, and more prone to damage during individual follicular extraction. Transactions by shearing forces will be higher with a higher chance of leaving behind vital cells that are essential for the healthy regeneration of the hair follicle.
 Therefore, only body donor hair follicles in the active anagen phase (which are strong even at the dermis level) are preferred for transplant. The hairs are shaved flush with the skin, 4-5  days prior to extraction. At the end of three to four days, the actively growing hair is easy to identify due to their increased length. If telogen hair is successfully extracted it will be bulbless hair and if transplanted will grow villous or thin hair  if at all it ever grows.
6.       Pre shaving pinpoints body donor hair whose growth cycles are more closely synchronized. Transplanting these hair results in a closer synchronization of the growth and synchronized shedding phase of these hairs at least, in the initial growth cycles. However, over couple of years, as the hair go through repeated growth cycles, the growth phase of these transplanted body hair lose their synchronicity. Without preshaving and selection of only non growing hair, a certain proportion (perhaps 10-30%) of the early anagen hairs could be mistaken for telogen hair because of factors like clear bulbs that are yet to get pigmented.
7.      Positioning of surgeon and also that of patient varies greatly from one area of body to that of other and even in the same area due to variable direction of hairs the angling and direction of instrument keeps changing unlike in case of scalp hair extraction.
8.      It has been said that the rate of growth: Body hair grows about 0.2 mm per day while scalp hair grows about .44 mm per day. The same body hair transferred to the scalp grows about .34 mm per day.
9.      predictability of growth- somewhat less than the scalp hairs
10.  Mix the various body as well as scalp donor hair in any particular area of scalp to achieve a uniform look and feel

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