Hair transplantation is a surgical technique that involves moving skin containing hair follicles from one part of the body (the donor site) to bald or balding parts (the recipient site). It is primarily used to treat male pattern baldness, whereby grafts containing hair follicles that are genetically resistant to balding are transplanted to bald scalp. However, it is also used to restore eye lashes, eye brows, beard hair, and to fill in scars caused by accidents and surgery such as face lifts and previous hair transplants. Hair transplantation differs from skin grafting in that grafts contain almost all of the epidermis and dermis surrounding the hair follicle, and many tiny grafts are transplanted rather than a single strip of skin.
Since hair naturally grows in follicles that contain groupings of 1 to 4 hairs, today’s most advanced techniques transplant these naturally occurring 1 – 4 hair "follicular units" in their natural groupings. Thus modern hair transplantation can achieve a natural appearance by mimicking nature hair for hair. This recent hair transplant procedure is called "Follicular Unit Transplantation."
The use of both scalp flaps, in which a band of tissue with its original blood supply is shifted to the bald area, and free grafts dates back to the 19th century. Modern transplant techniques began in Japan in the 1930s, where surgeons used small grafts, and even "follicular unit grafts" to replace damaged areas of eyebrows or lashes. They did not attempt to treat baldness per se. Their efforts did not receive worldwide attention at the time, and the traumas of World War II kept their advances isolated for another two decades.
The modern era of hair transplantation in the western world was ushered in the late 1950s, when New York dermatologist Norman Orentreich began to experiment with free donor grafts to balding areas in patients with male pattern baldness. Previously it had been thought that transplanted hair would thrive no more than the original hair at the "recipient" site. Dr. Orentreich demonstrated that such grafts were "donor dominant," as the new hairs grew and lasted just as they would have at their original home. Today Dr. Orentreich's practice still performs hair transplants.
For the next twenty years, surgeons worked on transplanting smaller grafts, but results were only minimally successful, with 2-4 mm "plugs" leading to a doll's head-like appearance. In the 1980s, Uebel in Brazil popularized using large numbers of small grafts, while in the United States Rassman began using thousands of “micrografts” in a single session.
In the late 1980s, Limmer introduced the use of the stereo-microscope to dissect a single donor strip into small micrografts. In 1995, Bernstein and Rassman published the first paper on "Follicular Unit Transplantation," where hair is transplanted exclusively in naturally occurring groups of 1-4 hairs. With microscopic dissection of donor pieces from an excised portion of scalp, individual follicular units containing but 1-4 hairs could be prepared and individually relocated into needle punctures in the recipient areas. Since the transplanted hair mimics the way hair grows in nature, close to natural results were attainable.
The follicular unit hair transplant procedure has continued to evolve, becoming more refined and minimally invasive as the size of the graft incisions have become smaller. These smaller and less invasive incisions enable surgeons to place a larger number of follicular unit grafts into a given area. With the new "gold standard" of ultra refined follicular unit hair transplantation, over 50 grafts can be placed per square centimeter, when appropriate for the patient.
Surgeons have also devoted more attention to the angle and orientation of the transplanted grafts. The adoption of the “lateral slit” technique in the early 2000s, enabled hair transplant surgeons to orient 2 to 4 hair follicular unit grafts so that they splay out across the scalp's surface. This enabled the transplanted hair to lie better on the scalp and provide better coverage to the bald areas. One disadvantage however, is that lateral incisions also tend to disrupt the scalp's vascularity more than sagitals. Thus sagital incisions transect less hairs and blood vessels assuming the cutting instruments are of the same size. One of the big advantages of sagitals is that they do a much better job of sliding in and around existing hairs to avoid follicle transection. This certainly makes a strong case for physicians who do not require shaving of the recipient area. The lateral incisions bisect existing hairs perpendicular (horizontal) like a T while sagital incisions run parallel (vertical) along side and in between existing hairs. The use of perpendicular (lateral/coronal) slits verses parallel (sagital) slits however, has been heavily debated on patient based hair transplant communities. Many elite hair transplant surgeons typically adopt a combination of both methods depending on what is best for the patient.
At an initial consultation, the surgeon analyzes the patient's scalp, discusses his preferences and expectations, and advises him/her on the best approach (e.g.,single vs. multiple sessions) and what results might reasonably be expected.
For several days prior to surgery the patient refrains from using any medicines, or alcohol, which might result in intraoperative bleeding and resultant poor "take" of the grafts. Pre-operative antibiotics are commonly prescribed to prevent wound or graft infections.
In recent years hair transplants have become less expensive. Prices typically range from $3.00 to $7.00 per graft, with $4 to $5 per graft being about average. Normally the price per graft also drops as the size of the surgical session increases. Depending on the needs of the patient a typical surgical session can range from 1,500 to over 4,000 grafts, resulting in a total cost of approximately $6000 to $15,000. A few clinics offer larger sessions of up to 6000 grafts in one sitting.
In the usual follicular unit procedure, the surgeon harvests a strip of skin from the posterior scalp, in an area of good hair growth. The excised strip is about 1-1.5 x 15-30 cm in size. While closing the resulting wound, assistants begin to dissect individual follicular unit grafts from the strip. Working with binocular microscopes, they carefully remove excess fibrous and fatty tissue while trying to avoid damage to the follicular cells that will be used for grafting.
The surgeon then uses a fine needle to puncture the sites for receiving the grafts, placing them in a predetermined density and pattern, and angling the wounds in a consistent fashion to promote a realistic hair pattern. The assistants generally do the final part of the procedure, inserting the individual grafts in place.
During the first ten days, virtually all of the transplanted hairs, inevitably traumatized by their relocation, will fall out ("shock loss"). After two to three months new hair will begin to grow from the moved follicles. The patient's hair will grow normally, and continue to thicken through the next six to nine months. Any subsequent hair loss is likely to be only from untreated areas. Some patients elect to use medications to retard such loss, while others plan a subsequent transplant procedure to deal with this eventuality.
There are two main ways in which donor grafts are extracted today. These are the Strip Harvesting Technique and the Follicular Unit Extraction (FUE) Technique.
The Strip Harvesting Technique involves removing a strip containing a large group of follicular units from the donor area - almost always from the back and sides of the scalp. The strip is then divided into grafts (or follicular units) containing 1 to 4 follicles.
The Follicular Unit Extraction (FUE) Technique involves removing one follicular unit at a time directly from the donor area – usually the back and sides, but also sometimes from the chest, legs or face (beard hair) - using a small punch usually of between 0.5mm and 1mm in diameter.
Other side effects include swelling of areas such as the scalp and forehead. If this becomes uncomfortable, medication may ease the swelling. Additionally, the patient must be careful if his scalp starts itching, as scratching will make it worse and cause scabs to form. A moisturizer or massage shampoo may be used in order to relieve the itching.