Hair Transplantation Procedures

Providing the reader with all of the tools necessary to select patients properly, design a treatment plan, and perform hair transplantation would be impossible within a single article. The purpose of this article is to provide a broad overview of the techniques used by many hair transplant surgeons, which serves as a foundation for the hair transplant surgeon. Hair transplantation is as much an art as it is a science, requiring both technical skill and artistic creativity.

Patient Selection and Preoperative Preparation

Hair transplantation is a surgical modality used for the correction of androgenic alopecia, scarring alopecia, and other causes of permanent alopecia. Since hair transplantation is a surgical procedure, all patients must be in good health. Many surgeons perform preoperative laboratory studies that include complete blood count, platelet count, serum chemistries, prothrombin time, pre–prothrombin time, and bleeding time. Some surgeons also check for human immunodeficiency antibodies, hepatitis B surface antibodies, and hepatitis C antibodies.

As with any cosmetic surgical procedure, the patient must have reasonable expectations. In fact, dissatisfaction after hair transplantation often arises from changed or unreasonable expectations rather than from complications or poor results. During initial consultation, the physician must learn the patient's goals and the circumstances that brought the patient to the decision to consider hair transplantation.

In addition, the physician must examine the patient, recognize the underlying cause of the patient's hair loss, and estimate the effect that time will have on the hair loss process. The patient must be provided with ample time to ask questions and arrive at a complete understanding of the procedure, expected outcome, and the changes that can be expected over time (eg, how results will change with future hair loss). Together with the patient, create a logical plan that will impart a natural-looking result both now and in the future.

Provide patients with both written and oral preoperative instructions. They need to be instructed to discontinue blood-thinning agents well before surgery to normalize bleeding time. Most surgeons require patients to discontinue aspirin or aspirin-containing products a minimum of 7-10 days before surgery. Nonsteroidal anti-inflammatory medications (eg, Advil, Motrin, Aleve) must be discontinued depending on the half-life of the agent. Consumption of alcoholic beverages has been shown to increase bleeding tendency and should be stopped a minimum of 7 days before surgery. Excessive vitamin E consumption is believed to increase bleeding tendency, and most surgeons advise patients to discontinue vitamin E supplements a minimum of 1 week before surgery. Consider inquiring about dietary and nonprescription alternative medications, since the list of herbal supplements that affect bleeding is growing.

Before and after hair transplantation (with permed hair).Before and after hair transplantation (with permed hair) with 1000 follicular grafts.Before and after hair transplantation with 1243 minigrafts and micrografts.

Preoperative Skin Preparation

To reduce risk of intraoperative wound contamination, many surgeons require patients to shampoo with 4% chlorhexidine gluconate the night before surgery. Note that significant keratitis has resulted from chlorhexidine remaining in the eye during surgery; therefore, one must instruct all patients to keep the cleanser out of their eyes. In addition, rare reports of anaphylaxis have been reported. Alternatives to chlorhexidine include Betadine shampoo, 3% chloroxylenol (Techni-Care), Dial liquid antimicrobial soap, and pHisoHex. In addition, some surgeons also require patients to shampoo their hair the morning before surgery and abstain from using hair products (eg, gel, mousse, hair spray).

Surgical preparation

Both the recipient and donor sites are scrubbed with 4% chlorhexidine gluconate or povidone-iodine (Betadine) solution. Some surgeons prefer to place the patient in a prone position when harvesting follicular grafts, while others seat patients for both harvesting and placing grafts. Hair at the donor site most often is trimmed to 1-mm length using scissors or an electric trimmer. To provide better exposure of the donor site, some surgeons prefer to tape the hair superior to (above) the donor site or to use sterile Kling gauze to improve visualization.

Anesthesia

In addition to local anesthesia, some surgeons also administer sedatives prior to and during the procedure.

Methods of administration

Most surgeons administer local anesthesia using a traditional syringe and a 30- or 27- gauge needle. A novel device has been created that precisely controls the infusion rate and pressure of local anesthetic using a microprocessor pump. This device, called the Wand or CompuMed - Featuring the Wand Handpiece, has been shown to produce less pain and discomfort than traditional injection.^[1]

Donor site

Several methods are used to provide anesthesia to the donor site. Some surgeons prefer to infiltrate the donor site locally or use a ring block using 1% or 2% lidocaine with 1:100,000 epinephrine. Other options include using a mixture of 1% lidocaine with 1:100,000 epinephrine and 0.5% bupivacaine or 0.5% lidocaine with 1:200,000 epinephrine.

Regardless of which concentration and agents are used, good skin turgor aids the surgeon when harvesting donor tissue and is extremely important when using punch harvesting or multistrip harvesting techniques. Consider the total dose of lidocaine, and ensure that nontoxic doses are used.

Recipient site

Local infiltration after completing a ring block remains the most commonly used technique for achieving anesthesia of the recipient site. Many surgeons use 1% lidocaine with 1:100,000 epinephrine, 2% lidocaine with 1:100,000 epinephrine, 0.5% lidocaine with 1:200,000 epinephrine, or a mixture of lidocaine with epinephrine and bupivacaine.

Tumescent anesthesia using standard Klein solution has been used and provides good anesthesia. Regardless of which method of anesthesia is used, ensure that the total dose of lidocaine remains below the toxic level.

Procedure

Donor harvesting

A number of different techniques are available for harvesting hair follicles; each technique has advantages and disadvantages. Regardless of which harvesting technique is used, the principle of protected hair follicles remains paramount. It is well known that some hairs are not lost to androgenic alopecia. Usually, the protected follicles are found in the inferoposterior scalp and inferior parietal scalp. It is essential that only protected follicles be transplanted to ensure maximal survivability. With any of the below techniques, the punch, blade, and blades used are angled parallel to the hair follicles and not perpendicular to the scalp itself in order to minimize transection of hair follicles.

Punch harvesting

This technique was used most commonly for harvesting donor follicles until the late 1980s or early 1990s, when excision with or without a multibladed knife became used more widely because of its many advantages. With the punch harvesting technique, a small hand engine is used (which spins approximately 10,000-15,000 revolutions per minute) with a 2- to 6-mm punch. As the punch spins, it is pressed into the donor scalp parallel to the hair to minimize transection of any hair follicles. When the desired depth is achieved, the punch is withdrawn and moved to the next donor site to be excised.

Once punching of the number of grafts desired is complete, the graft may be lifted gently, using forceps or a sterile needle, and cut free using scissors (leaving approximately 1 mm of fat at the base of follicle). Defects created from harvesting may be left to heal by secondary intention or may be closed using sutures or skin staples. Healing by secondary intention has been abandoned, largely because of results that are cosmetically inferior.

Excision

The donor site is excised as an elongated fusiform ellipse of full-thickness scalp using a scalpel blade size 10 or 15. Take care when excising not to damage hair follicles at the edge of the donor tissue. The resultant defect is closed using suture or skin staples, and the scar is minimal. Then, donor tissue is dissected carefully into the desired number of grafts, which can vary in size.

Strip harvesting

A scalpel containing 2 or more size 15 blades mounted in parallel is used to cut strips of donor tissue. This facilitates the division of donor scalp into minigrafts and micrografts. Several multibladed scalpel handles currently are available that can accommodate as many as 6 or more No. 15 blades, which most commonly are spaced 1.5-2.5 mm apart. This technique may carry a higher risk of follicle transection than excision.

Creating and dissecting grafts

Grafts obtained by punch grafting can be transplanted directly or cut into smaller grafts using a size 15 blade or razor blade. These round grafts can be cut into halves or quarters, or they can be dissected down to single hair grafts. Grafts harvested by excision or strip harvesting can be cut to single grafts, minigrafts, or micrografts by using a size 15 blade or razor blade.

Most surgeons use magnifying loupes or a dissecting microscope to aid the dissection of grafts. Some surgeons believe that follicular grafts (ie, those that are essentially a single follicular unit) offer better results, although further studies are needed.^[2]

Creating recipient sites

Several techniques are used for creating and preparing recipient sites (where grafts are to be placed); each has several advantages and disadvantages.

• Single hair and slit grafting: Using a scalpel with a No. 15 blade or number 3764 beaver blade or an 18-gauge needle, 18-gauge Yeh needle, or NoKor needle, multiple 0.5- to 3-mm slits are made in the scalp in which the grafts are placed (see Dilator use, below) Single hair or micrografting is most often used to recreate the frontal hairline. Magnification with illumination with polarized light emission diodes may reduce the risk of follicle transection during the creation of slits.^[3]
• Dilation (modified slit grafting): Sharp 0.8- to 1.6-mm dilators are inserted directly into the scalp, pushing the scalp aside to provide hemostasis. Micrografting (grafts containing 1-2 hair follicles) or minigrafting can be performed using dilation. Micrografting most often is used to recreate the frontal hairline. This method has not become popular as it is typically slower than slit grafting and may result in compression of the grafts, especially when more than one hair follicle is grafted.
• Punch grafting: Using 1- to 4-mm diameter punches, a defect is created at the recipient site into which the graft may be inserted. Occasionally, bleeding occurs that can be tamponaded easily by inserting a dilator or the graft. The larger the size of the graft, the more likely it is to have what is termed a "doll's hair" or "cornrow" appearance.
• Laser-assisted grafting: Carbon dioxide laser has been used to create recipient sites.^[4] To date, optimal laser parameters have not been determined. Many surgeons use 35-50 W at an interval of 0.05 seconds. Significant delay in the growth of the transplanted hairs usually occurs after laser-assisted transplantation.

Dilator use

After creating recipient sites, dilators may be used to enlarge the opening, by pushing adjacent scalp aside, and/or to provide hemostasis. In addition, many surgeons believe that this aids in the insertion of grafts; therefore, lesser trauma results to the grafts during insertion.

Graft insertion

Most surgeons use jeweler's forceps or similar small non–toothed forceps to insert grafts. Gently insert a graft by grasping the fat immediately beneath it to minimize trauma to the follicle. Some surgeons use a needle to insert and tease grafts gently into place. More recently, implantation devices have been designed that create recipient site and insert grafts.

Medications and Postoperative Dressings

Antibiotic use

Significant controversy remains regarding the use of prophylactic antibiotics in hair transplant surgery, since few studies support the use of antibiotics. Although prophylactic antibiotics can decrease the risk of wound infection, the risk of hypersensitivity reactions and the emergence of resistant organisms need to be considered. The most appropriate time to administer prophylactic oral antibiotics (as single dose) is 1 hour preoperatively; however, if endocarditis prophylaxis is necessary, an additional postoperative dose is administered.

For most patients, first-generation cephalosporin is used, unless a history of cephalosporin allergy exists. If cephalosporin hypersensitivity exists, azithromycin or ciprofloxacin may be substituted. Some surgeons also use topical antibiotics during the postoperative period to reduce risk of wound infection, although no benefit has been established yet. Some surgeons use oral antibiotics for 3-5 days postoperatively to reduce risk of infection.

Corticosteroids

Many surgeons administer oral or intramuscular corticosteroids to reduce postoperative swelling, although few data are available supporting this practice.

Pain medications

Some patients require oral narcotics for the first few days after hair transplantation. Usually, Tylenol with codeine # 3, Percocet, or Lortab 5 is sufficient to alleviate most postoperative discomfort.

Postoperative dressings

Most surgeons advocate use of surgical dressings to minimize risk of graft loss. Many surgeons apply (1) topical antibiotic, (2) Telfa nonstick gauze, (3) gauze, (4) Kerlix gauze, and (5) Coban wrap to create a turbanlike dressing. Most often, this dressing is removed after 24 hours; no dressing is required thereafter. Some surgeons use no postoperative dressing and require patients to wear a baseball cap.

Complications

As with any surgical procedure, a risk exists of the following infrequent complications:

• Bleeding
• Infection
• Scarring at donor site
• Scarring at recipient sites
• Dyspigmentation at recipient sites
• Cobblestone appearance at recipient sites
• Failure of graft
• Cyst formation

Postoperative edema is expected; therefore, it is not a complication, although it can be severe.

 

source :medscape.com