Hair Loss Restoration Treatment Procedures

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Hair loss can occur from a combination of aging, changes in hormones, and a family history of baldness, as well as from burns or trauma. There are several different techniques used for hair restoration, sometimes performed in combination, and these may include the following:

· Scalp reduction

· Tissue expansion

· Scalp flaps

· Hair transplantation (including plugs, strip grafts, mingrafts, micrografts, and follicular unit transplants)



Scalp reduction, also referred to as advancement flap surgery, is generally used for individuals requiring coverage of bald areas at the top and back of the head, and may not be beneficial to those requiring coverage of the frontal hairline. For this procedure, the scalp is injected with a local anesthetic, then a segment of the bald scalp is removed. The segment removed typically resembles an inverted Y-shape, particularly if a large amount of coverage is required, but it may also resemble a U, a pointed oval, or some other shape. The skin surrounding the removed segment is loosened and pulled, then sections of hair-bearing scalp are pulled forward, brought together, and closed with stitches.
Tissue expansion is a procedure which has been commonly used in reconstructive surgery for burn wounds and other injuries involving significant skin loss. The use of tissue expansion for hair reconstruction tends to result in significant coverage in a relatively short period of time. For this procedure, a tissue expander, or a balloon-like device, is inserted beneath an area of hair-bearing scalp which lies next to a bald or thinning area of the head. Over a period of weeks, this device is gradually inflated with salt water, forcing the skin to expand and ultimately produce new skin cells. This will cause a bulge to form beneath the hair-bearing scalp, usually several weeks after insertion. Typically within two months following the first surgery to insert the tissue expander, the skin will be sufficiently stretched and ready for a second procedure to move the expanded skin over to the adjacent bald or thinning area.
Flap surgery is a procedure which has been performed for over 20 years and is generally thought to be able to cover large areas of a balding scalp fairly quickly. One flap is capable of achieving the results acquired by 350 or more punch grafts. The surgery is customized for each patient, thus the size and placement of the flap will depend upon each patient’s goals and needs. For flap surgery, a section of bald scalp is cut out and replaced by a flap of hair-bearing scalp. The hair-bearing flap is lifted off its surface, moved to its new position and sewn into place, all the while still attached at one end to its original blood supply. The resulting scar is typically hidden by the relocated hair. Flap surgery is often combined with other hair restoration procedures: for better coverage of the crown of the head, it may be combined with scalp reduction; for better frontal coverage and a more natural hairline, it may be combined with tissue expansion.
Hair transplantation is the procedure designed to fill in balding areas of a patient’s scalp using that patient’s own hair. It is important to note that no ‘new’ hair is added but rather existing hair is simply transplanted, thus the actual volume of hair will not increase. Hair transplantation is the most widely available hair restoration technique and the most likely approach that a hair restoration clinic will offer to you. There are several different variations on the general theme of transplanting hair from the back of the sclpa to blad areas. When hair transplantation was first developed, quite large "plugs" of skin with around 20 hair follicles in each plug would be extracted from the back of the scalp and implanted. The problem was that the result looked very artificial and produced a "doll hair" corrow look. However, over the last 20 years many improvements have been made in hair transplantation and today a good hair transplant surgeon can produce a very natural looking result. The most advanced form of hair transplantation currently available involves the transplantation of follciular units - small pieces of skin containing no more than five hair follicles and on average only three hair follicles each, and even single hair follicles. These implants are arranged to mimic the natural pattern of hair growth and can give a very effective and pleasing result.

The best candidate for hair transplant surgery is an individual with healthy hair growth at the sides and back of the head which can serve as donor sites. Patients should be in good physical health, psychologically stable, and have realistic expectations. There are several factors which may impact the outcome of hair transplantation, such as hair color and texture. Those with lighter hair color, as well as those with thicker hair, may achieve better results than those with darker or thinner hair. The procedure tends to work best on men with male pattern baldness once the hair loss has stabilized.

It is very important that you have realistic expectations because, though hair transplantation can enhance your appearance and increase your self confidence, it may not necessarily alter your looks to match your desired ideal. Because there are limits to what the procedure can achieve, hair transplant surgery may not be suitable for individuals with very little hair.

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The actual hair transplant information in terms of percentage of hair that can be harvested from the donor site without causing any visible scarring during its closing, or causing very little hair being left at the donor site for future hair restoration surgery, is very crucial for a hair transplant surgeon. And depending upon the Hair transplant information calculated as demand/supply ratio, an expert hair restoration surgeon exploits the donor hair for the greatest benefit of the patient according to the following procedures:

· Size of donor area and tissue to be collected

· Preparing the occipital scalp for donor skin removal

· Method of donor tissue collection

Size of donor area and tissue to be collected

This page refers to the procedure generally used for patients with androgenetic alopecia. The procedure will vary somewhat depending on the personal preference of the surgeon, and will vary even more if you have a form of alopecia other than androgenetic alopecia that is being surgically restored.

Planning the donor site is just as important is planning the hair implant recipient site in hair restoration. The donor area has to be preserved as much as possible, you don’t want an irregular shaped occipital scalp hair growth or a large scar from the removal of the donor hair follicles. The primary issue for the hair transplant surgeon in planning the donor site is how big it is and how much skin should be taken to provide enough hair follicles for the transplant session. Not all donor sites are the same size in hair transplant patients. Some men and women have quite large areas of occipital scalp where the hair follicles remain unaffected by androgenetic alopecia. In other patients, the androgenetic alopecia has spread far back on the scalp and the occipital scalp hair growth area is relatively small. In addition, there are some people in whom their androgenetic alopecia is so extensive that the hair follicles on the occipital scalp are also affected to some extent and the hairs are finer and thinner than would be expected. If the donor area is too small or the area is affected by androgenetic alopecia then the individual may not be a suitable candidate for hair restoration.

Some experience is required on the part of the hair transplant surgeon to correctly define the area of donor hair on the occipital area that is unaffected by androgenetic alopecia. It is important to get it right as transplanting hair follicles that are androgen responsive will lead to transplanted hair follicles miniaturizing in response to the androgen hormones. Also, the surgeon must leave enough hair behind after removing the donor hair follicles to ensure a natural look to the occipital hair line. It is generally believed that the “safe” area of potential donor hair follicles resistant to androgenetic alopecia is in the area from the lower hairline at the back of the neck, up to an imaginary line running around the back of the head about 2cm above the openings of the ears. This defines the maximum extent of the potential donor area for all but a few individuals. However, when actually removing the donor skin, the surgeon must leave margins above and below the removed hair follicles. The surgeon also has to take into account the possibility that the patient may need more hair restoration procedures in the future. Bearing these limitations in mind the surgeon will identify an area of skin to remove.

Preparing the occipital scalp for donor skin removal

At the start of the procedure, you, as a patient, will be dressed in a surgical gown, or at least you will be asked to cover your upper body and around your neck in a disposable apron. You will be positioned face down on an operating table with your head on a prone pillow – it has a hole in the middle for your face to go into so you can breathe! The area of skin at the back of your head will be sterilized with one or more solutions swabbed over the skin and hair. The long hair that you have hopefully been growing to use later to cover over the sutures, will be combed out of the way and held in place with hair clips. The area of skin from which the donor hair follicles will be cut, will be shaved with clippers or cut with scissors so that the long hair doesn’t get in the way of cutting the skin and later when the skin is microdissected to obtain the hair follicles. The hair is not completely removed down to the skin surface, about 2mm of hair is left above the skin surface so that the surgeon can see where the hair follicles are when he cuts the donor skin. The skin is swabbed again to get rid of the loose, cut hair and to repeat the sterilization. Usually the solution is iodine (Betadine) or chlorhexidine (especially if you are allergic to iodine).

To prepare the skin ready for cutting, your skin will be injected with a saline solution and then a local anaesthetic or alternatively you may receive both saline and anaesthetic as a mixed solution. The intention of the saline is to increase tumescence in the skin that is, to make the skin relatively hard. This makes it easier to cut with a scalpel and ensures nice clean edges to the cut skin which makes healing of the wound quicker. It also spreads the hair follicles apart so they are easier to see and to cut between with the scalpel blade. The local injections can be painful, although the pain should be brief until the local anaesthetic takes effect. To overcome the brief pain during injection of the saline and local anaesthetic, some surgeons offer the option of a partial systemic anaesthetic like nitrous oxide. You usually administer this to yourself, by breathing it through a mask you apply to your mouth as and when you feel you need it, during the injection of saline and local anaesthetic. You should remain awake throughout the procedure. The breathable anaesthetic is only used until the local injected anaesthetic takes hold.

Method of donor tissue collection
The next step is for the surgeon to actually cut the donor skin area. Most hair transplant surgeons currently (as of 2004) use a multi bladed knife to remove a strip of skin from the occipital scalp. The distance between the blades and the length of cut determines the size of the skin area that is removed. The multi bladed knife can be resized to change the distance between the blades. The surgeon will determine how much skin is needed and position the blades of the knife appropriately. The scalpel blades are inserted into the skin at one side of the head at an angle such that the blades are parallel to the hair follicles in the skin. The surgeon can predict how angled the hair follicles are in the skin by observing the angle of hair growth coming from the hair follicles. The cut is relatively quick in the hands of an experienced surgeon. It can take less than 30 seconds. However, it can take longer if you are one of the few individuals in whom the angle of the hair follicles changes across the scalp. Then the surgeon has to go more slowly and carefully to ensure he/she does not cut into the hair follicles.

The surgeon will then cut across the skin to make the strip of donor hair follicles. If you have already had one or more procedures done, the surgeon will cut the strip of skin just next to where the previous strip of skin was cut. The surgeon will cut the new strip of donor skin such that it also just cuts out the scar left from the previous operation. In this way, the surgeon can ensure that, regardless of how many implant procedures you have, you only ever have one scar on the occipital scalp. Just how much skin is removed depends on the size of the recipient area that needs to be implanted and the density of your hair follicles. Roughly speaking, the density of hairs in the donor region of the scalp typically ranges from 70 to 120 follicular units per square centimeter, with a median of 80. Therefore, in the typical patient, a 20-cm2 donor strip (20 cm in length by 1 cm in width) would be required for a 1600-graft procedure.

The strips are then cut away from the scalp. Usually, the surgeon or nurse will pull gently on one end of the donor strip with forceps and as the skin is lifted up above the remaining scalp skin, a pair of surgical scissors will be used to cut underneath the hair follicles to release the skin strip from the scalp. This is then put into a saline solution in a plastic dish in an ice bucket. This is taken away for further processing to make the grafts ready for implanting. What is left is a usually a narrow elliptical hole in the occipital scalp skin. If there is bleeding from some of the larger blood vessels, they may be cauterized. The wound is then sutured (sewn) together, often with a single running stitch. Some hair transplant surgeons use biodegradeable sutures that eventually fall out. Most however, use normal sutures that need to be taken out by a doctor at a later date. It will take a while until the grafts have been dissected ready for implantation. During this time you will probably be free to sit up and read or watch a video.

The donor skin is then processed to isolate the follicular units for transplantation.

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After the hair transplant donor site has been planned and the donor skin excised, the donor skin strip must be dissected and processed to make grafts ready for implantation.

Size of donor area and tissue to be collected

The donor strip of skin is taken to a preparation room. Here the skin is dissected into grafts ready for implantation. In modern clinics the donor skin is dissected by a team of highly trained assistants. There can be three to five, and sometimes even seven or eight, technicians dissecting the skin simultaneously. Arguably the best, hair transplant clinics have their technicians divide up the donor skin using stereo dissecting microscopes.

Using the binocular microscope, the assistants subdivide the single strip into thin slivers 2 to 3 follicular units wide. These individual slivers are then further dissected into individual follicular units. The tissue is handled with fine forceps and cut with small scalpels. The tissue is held with forceps on one side, the scalpel is angled parallel to the angle of the hair follicles, and the skin is cut to the side of a follicular unit. If the technicians see significantly damaged hair follicles or hair follicle missing a bulb, they will cut these away from the follicular units and discard them. They cut off much of the non hair bearing scalp skin around the hair follicles. The smaller the follicular unit the quicker and better it will heal into the skin once it is implanted. It is also less likely to leave a visible scar. The grafts, separated by numbers of hairs, are kept in chilled saline until the time of implantation, separated by hair number. The mean number of hairs per graft is 2.2 to 2.3, so most grafts contain 2 or 3 hairs. Follicular units of ones and twos will be used towards the front to make the hair line, while follicular units of three and four hair follicles will be used to fill in behind the implanted hair line.

The use of dissecting stereo microscopes during hair transplant graft dissection has only recently been advocated as a means of reducing hair follicle damage and improving graft growth. The first publication on their use was in 1994 although the top hair transplant doctors were using microscopes for dissection since about 1990. If a dissecting microscope is not used to cut up the donor skin strip, it has been found that it is much more likely that hair follicles will be cut and damaged. Using the microscope, technicians can see the hair follicles much better and so are less likely to cut through a hair follicle. One study evaluated the prevalence of hair follicle transection in grafts prepared with and without the dissecting stereomicroscope. Half as much transection (10% vs 20%) was noted in grafts prepared with microscopes, suggesting their use may be associated with less hair follicle trauma and improved hair growth (Cooley 1999).

To be fair to those surgeons that do not have their technicians use microscopes when they cut up the donor skin into grafts, some studies have shown that implanted hair follicles can grow even after sustaining mild to moderate damage and that sometimes cutting the hair follicles in two can actually lead to two hair follicles being produced from one! The issue is how much damage a hair follicle can sustain before it becomes so damaged that it cannot grow. Those follicles from which more than a third of the lower follicle and bulb region have been cut will not grow. In light of this, dissecting hair follicles under a microscope is probably the safest way to ensure that the dissected hair follicles are healthy and will survive and grow after implantation. One study that compared implanted hair follicles that had been dissected with microscopes or loupes suggested microscope use increased the hair yield by as much as 20% (Berstein 199.
Dissecting the hair follicles under a microscope also enables a relatively new development in hair restoration to take place – follicular unit grafting. Hair follicles often grow in natural clusters of twos, threes, and fours. Using the stereo dissecting microscope, the hair follicles in the donor skin can be divided into their natural “follicular units” and implanted in these units. This makes for a much more natural looking transplant result. So in short, microscopic dissection results in grafts that are smaller and contain a minimum amount of scalp skin. These grafts can be placed into smaller recipient sites, and this theoretically allows for a greater hair density, faster healing, and less trauma to any existing hairs in the implant recipient area. In addition, transplanting grafts with a limited amount of skin around them minimizes any changes in pigmentation and texture of the recipient scalp skin. So with the donor skin now dissected into follicular units the next part of the procedure, the implantation, can begin.

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Hair Transplant Recipient Site Preparation and Implantation


Below is an overview of the step by step procedure involved in hair restoration surgery. This applies primarily to procedures using follicular unit transplantation, but a similar approach will be used in other types of hair restoration surgery.
Implant site preparation

To prepare you, the hair transplant patient, for receiving the graft implants, you will be asked to sit in a surgical chair or in a semi supine position on a surgery table. There are arguments about which position is more comfortable and which leads to fewer complications with the procedure. So far no clear winner has emerged. The advantage of the semi supine position is that it reduces the chances of fainting or dizziness during the procedure. This can happen before the anesthesia is injected into the implant area, but rarely happens once the anesthesia takes effect. On the other hand, a sitting position reduces the amount of bleeding when the grafts are being implanted. The vertex (front and top of the scalp) has a high density of blood vessels in it. When the skin is cut on the scalp it can bleed quite a lot. A sitting position helps drain blood away from the scalp and in so doing reduces the amount of blood that bleeds from the implant wounds. Some surgeons may arrange for you to lie down for the initial anesthetic injection and then have you sit in a chair for the implant procedure to get the best of both approaches.

The hair line

The area of skin for implantation is sterilized by swabbing with an antimicrobial solution. Anesthetic is injected locally in the area of skin ready for implantation. Once the anesthetic has taken effect, the implantation procedure can begin. For those with classic androgenetic alopecia in a male pattern and recession of the frontal hair line, the hair line is the first problem to be addressed. The surgeon, rather than any assistants, should be the one to make the incisions for the graft implants that will form the hair line. In general the surgeon will also be the one that fills the hair line incisions with grafts, although sometimes a nurse will do it. The hair line is the most important part of any hair restoration procedure. This will determine whether the result looks natural or artificial. For the hair line to look as natural as possible, the surgeon must make the line reasonably bilaterally symmetrical although perfect bilateral symmetry of the implanted hair line is unlikely. The hair line needs to adjusted on each side depending on the shape of the face - particularly if your face is not very symmetrical! When the hair follicles are actually implanted, only the small one, and occasionally two, hair follicle unit grafts are implanted into the hair line. They may not be in an exact line as, if you look at a natural hair line, there are always a few odd follicles out of line. A very slight “wiggle” in the hair line makes it look just that much more natural.

Making the incisions and inserting the hair follicles
Different hair transplant doctors have different personal preferences for how they make the incisions into the skin ready to receive the hair follicle grafts. Some use needles of 16-18 gauge – which is pretty small. Others use small scalpels and make little slits in the skin into which the implants can be squeezed. A few hair transplant surgeons still use punch biopsies, although punch biopsies are only made as small as 2mm which is, for the most part, too large for the modern practice of follicular unit implantation. There are also some special implantation devices available that some surgeons use. Regardless, the objective is to make nice clean, small wounds ready to receive the hair follicle implants. The hair follicle units are then pushed into the small wounds using watchmaker’s forceps. Because the follicular units are so small and there are often many of them to implant, there are usually two nurses working on either side of the head to speed up the implantation process. Time is important, the longer the hair follicle grafts are lying in cold saline the longer they are away from nutrients in the blood that they need to grow. This is probably why it takes so long for transplanted hair follicles to grow after a procedure. The hair follicles have been starved and that usually sends them into a state of suspended animation (telogen). Once the grafts are healed in and they start receiving food via the blood again, so the hair follicles can repair themselves, rearrange themselves and start growing hair.

Pattern of implantation

The pattern of incisions and hair follicle implantation is very important for ensuring a natural looking result. Hair follicles grow at an angle over the scalp and the angle changes depending on what area of the scalp you look at. For most people, though not everyone, the hair on the top of the scalp grows in a clockwise whorl pattern with the center of the whorl at the vertex. For this reason, if there is a parting it is usually on the left hand side of the scalp. It is much harder to part hair on the right and have the hair lay flat. Because of this whorl pattern, the surgeon will similarly arrange the implanted hair to match this natural hair growth whorl. The hairs will be implanted into the skin at an angle consistent with any remaining hair and pointing in a direction that follows the whorl pattern. The parting is also an important consideration for the surgeon. He/she may implant hair follicle units at a slightly higher density around the natural parting than on the opposite side of the scalp. This will help give the parting a normal looking hair follicle density.

Whilst the ideal is to give you a normal hair density in a natural growth pattern over the entire bald area, the limitations on how many donor hair follicles you have and the size of the recipient area to cover will modify the nature of the implantation. If there aren’t enough hair follicles to transplant, then the surgeon may implant more towards the front of the head than the back so that the hair can be grown longer and combed back to cover the thinner areas behind. The surgeon must also modify the implantation when there is more than one surgical procedure in the complete hair restoration. If subsequent transplant sessions are expected, then the implanted follicles may be more spread out than would be expected with just one implantation procedure. The surgeon is leaving room for hair follicles to be implanted in the next session in between the grafts implanted in the current session. This means the total hair restoration is built up over multiple session, and until the final session is done, it is not possible to determine just how natural (or not) the transplant looks.

Eventually all the grafts should be implanted and the basic procedure is complete.

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In the 1990's Micro Grafts and Mini Grafts were widely used for hair transplant surgery in mega sessions to achieve acceptable hair density in first session of the hair replacement surgery.
Micro and mini grafts are still used as exclusive hair restoration procedures and involve extensive graft preparation and handling along with tremendous assistant support. Teams of 8-10 surgical assistants work with a hair restoration surgeon for 8-10 hours together to isolate the grafts. Though these mega-sessions result in aesthetically superior results, it is considered to be a highly demanding hair restoration procedure on the part of a hair transplant surgeon because of the long time taken for isolating hair transplant grafts.

Problems with Micro Grafts and Mini Grafts

Laser hair restoration was initially thought of as a hair restoration procedure which could remove the graft compression problem associated with micro and mini-grafts.

Graft compression is the result of the hair transplant procedure where follicular hair transplants with 1-2 and 3-4 haired follicular grafts are inserted instead of single follicular transplants in order to achieve a high density. And when thousands of such grafts are closely placed together in mega sessions, the scalp skin pushes or squeezes the hairs through the slits, making them appear as if they are growing from a single hole. This tufted hair effect is called graft compression. Sometimes overcrowding or graft compression also led to the exclusion of the grafts.

Initial Experiments for Laser hair restoration

As laser surgery was becoming popular with most of surgeries performed, Laser hair restoration was seen to have much potential in solving the graft compression problem associated with mini-grafts and micro-grafts by the use of highly focused laser beam.

It was thought that when a laser beam would be used for preparing a narrow slot in the scalp for the implanting hair graft it would offer a better hair transplant procedure. By actually removing tissue, it was thought that laser hair transplant would reduce the risk of graft compression, and produce more natural results.

The first laser hair transplant procedure was performed by Dr. Unger and David in 1992 using the carbon dioxide laser. The subsequent laser hair restoration studies were undertaken with the hope to achieve a reduction in bleeding due to photocoagulation effect of laser. It was thought that laser hair restoration would lead to more natural hair restoration results due to consistent recipient channel depths produced by uniformly vaporized tissue. The proponents of laser hair transplantation thought that by using a laser hair transplant technique they would be able to transplant hundreds of grafts together which could reduce the time of a hair transplant surgery many fold.

Flaws of Laser Hair Transplants
But the histological and histo-chemical analysis in laser hair transplant experiments had a different story to tell. In all laser treated specimens, the damage to the tissue was more evident than seen with the standard punch technique. Thermal damage caused by the high energy of lasers in all laser hair restoration studies was found to be statistically significant for both the connective tissue and the adnexal structures (hair follicle, sebaceous glands and eccrine).

Even with modifications and advances in laser hair transplant technology, there was not seen to be much possibility for laser hair transplant surgery to replace the conventional methods of hair transplant surgery, however tedious and time consuming they had been.

Why did laser hair restoration fail

Most of the reports and experiments confirmed that not only is laser hair transplant inappropriate for follicular unit transplantation, it is actually detrimental regardless of whatever different modifications and variations of laser hair restoration procedure it is tried.

The reason for failure of laser hair restoration lies in the procedure itself and has nothing do with a hair transplant surgeon not being efficient in the procedure. The laser beams have the properties of "selective photo-thermolysis" (this is the ability to destroy a specific target without injuring the surrounding tissue). Hair transplant surgery is different in this regard from other surgeries because of the lack of a target tissue. And when one is using laser hair transplant surgery for channel creation, it is actually making use of the destructive properties of the laser. The laser literally burns a recipient hole in the skin and actually damages the surrounding skin in the process. And all the claims made by laser companies for a new class of laser causing no thermal damage, is anything but true. Regardless of the source and the type, a laser is something which causes thermal damage by burning the tissue by its high energy. The laser hair restoration technique always leaves surface change and scarring. Not only this, high energy laser beams used for laser hair transplants may damage hairs existing near the implant site because of burning of the surrounding tissue.

There is another drawback of laser hair transplant surgery which is more critical than the one discussed above. The high energy of the laser beam leads to the closing of the blood vessels. This characteristic feature of the laser beam is useful in other types of surgery where it helps to close wounds and provides quick healing. But in the case of hair replacement surgery, blood supply is very crucial for nourishing the grafts after they are transplanted. This is the main concern about a laser hair transplant surgery. Laser assisted transplants either are not able to grow or heal more slowly and have unpredictable growth due to impaired blood flow.

The thermal damage caused by the laser hair restoration to the surrounding tissue destroys the collagen and weakens the elastic support around the newly transplanted grafts. It also increases the coagulum (clot) around the graft which, in turn, decreases oxygen perfusion and retards healing. The uniformly created channels created by laser hair transplant surgery lose all its promise when the laser "loosens" the "snug fit" between the transplanted graft and recipient site. And this is the reason why laser hair restoration results in unpredicted and slow growth of the hair follicle.

The advantage of laser towards decreasing bleeding at the recipient site is also of not much use. A hair transplantation surgeon can decrease bleeding more effectively by the use of precision instruments and better hair transplant procedures than using laser.

Regardless the hair restoration procedure a hair transplant doctor uses, maximizing the growth of a transplant is the primary aim of any hair transplant surgery. And whatever the type of implanted graft, whether it is a single follicular unit or a group of follicular units, restoring the blood supply to the graft is of utmost importance. Since the laser hair transplant surgery fails to accomplish the vital function of restoring the blood flow, laser hair restoration is to be simply ignored as a hair restoration procedure.