Although many technical advances have been made in the field of surgical hair restoration over the past decade, particularly with the widespread adoption of follicular transplantation, many problems remain. The majority revolve around doctors recommending surgery for patients who are not good candidates. The most common reasons that patients should not proceed with surgery are that they are too young and that their hair loss pattern is too unpredictable. Young persons also have expectations that are typically too high – often demanding the density and hairline of a teenager. Many people who are in the early stages of hair loss should simply be treated with medications, rather than being rushed to go under the knife. And some patients are just not mature enough to make level-headed decisions when their problem is so emotional.
In general, the younger the patient, the more cautious the practitioner should be to operate, particularly if the patient has a family history of Norwood Class VII hair loss, or diffuse un-patterned alopecia.
Problems also occur when the doctor fails to adequately evaluate the patient’s donor hair supply and then does not have enough hair to accomplish the patient’s goals. Careful measurement of a patient’s density and other scalp characteristics will allow the surgeon to know exactly how much hair is available for transplantation and enable him/her to design a pattern for the restoration that can be achieved within those constraints.
In all of these situations, spending a little extra time listening to the patient’s concerns, examining the patient more carefully and then recommending a treatment plan that is consistent with what actually can be accomplished, will go a long way towards having satisfied patients. Unfortunately, scientific advances will improve only the technical aspects of the hair restoration process and will do little to insure that the procedure will be performed with the right planning or on the appropriate patient.
The improvement in surgical techniques that have enabled an ever increasing number of grafts to be placed into ever smaller recipient sites had nearly reached its limit and the limitations of the donor supply remain the major constraint for patients getting back a full head of hair. Despite the great initial enthusiasm of follicular unit extraction, a technique where hair can be harvested directly from the donor scalp (or even the body) without a linear scar, this procedure has added relatively little towards increasing the patient’s total hair supply available for a transplant. The major breakthrough will come when the donor supply can be expanded though cloning. Although some recent progress had been made in this area (particularly in animal models) the ability to clone human hair is at least 5 to 10 years away.
1. The greatest mistake a doctor can make when treating a patient with hair loss is to perform a hair transplant on a person that is too young, as expectations are generally very high and the pattern of future hair loss unpredictable.
2. Chronic sun exposure over one’s lifetime has a much more significant negative impact on the outcome of the hair transplant than peri-operative sun exposure.
3. A bleeding diathesis, significant enough to impact the surgery, can be generally picked up in the patient’s history; however OTC medications often go unreported (such as non-steroidals) and should be asked for specifically.
4. Depression is possibly the most common psychiatric disorder encountered in patient’s seeking hair transplantation, but it is also a common symptom of those persons experiencing hair loss. The doctor must differentiate between a reasonable emotional response to balding and a depression that requires psychiatric counseling.
5. In performing a hair transplant, the physician must balance the patient’s present and future needs for hair with the present and future availability of the donor supply. It is well known that one’s balding pattern progresses over time. What is less appreciated is that the donor zone may change as well.
6. The patient’s donor supply depends upon a number of factors including the physical dimensions of the permanent zone, scalp laxity, donor density, hair characteristics, and most importantly, the degree of miniaturization in the donor area – since this is a window into the future stability of the donor supply.
7. Patients with very loose scalps often heal with widened donor scars.
8. One should never assume that a person’s hair loss is stable. Hair loss tends to progress over time. Even patients who show a good response to finasteride will eventually lose more hair.
9. The position of the normal adult male hairline is approximately 1.5 cm above the upper brow crease. Avoid placing the newly transplanted hairline at the adolescent position, rather than one appropriate for an adult.
10. A way to avoid having a hair transplant with a look that is too thin is to limit the extent of coverage to the front and mid-scalp until an adequate donor supply and a limited balding pattern can be reasonably assured – an assurance that can only come after the patient ages. Until that time, it is best to avoid adding coverage to the crown.
Hair Transplantation has been available as a treatment for hair loss for over 40 years. 
Through a majority of that time, hair transplantation was characterized by the use of plugs, slit grafts, flaps and mini-micro grafts. Although these were the best tools available to physicians at the time, they were incapable of producing consistently natural results.
With the introduction of Follicular Unit Transplantation (FUT) in 1995, doctors were finally able to produce these natural results.  But the mere capability to produce them did not necessarily ensure that these natural results would actually be achieved. The FUT procedure presented new challenges to the hair restoration surgeon and only when the procedure was properly planned and perfectly executed, would the patient truly benefit from the power of this new technique.
The ability of follicular unit grafts to mimic nature soon produced results that were completely undetectable. This is the hallmark of Follicular Unit Hair Transplantation.  Of equal importance, however, is hair conservation – the one to one correspondence between what is harvested from the donor area and what ultimately grows in the recipient scalp. Since a finite donor supply is the main constraint in hair transplantation, the preservation of hair is a fundamental aspect of every technique. However, unlike the older procedures that used large grafts, the delicate follicular units are easily traumatized and very susceptible to desiccation, making follicular unit transplantation procedures, involving thousands of grafts, particularly challenging. 
As of this writing, the vast majority of hair transplants performed in the United States use Follicular Unit Transplant techniques. Due to limited space, this review will focus on only this technique and not on the older procedures. Nor will it focus on Follicular Unit Extraction, since this technique is still evolving and the ways to avoid the major pitfalls of this procedure are still being worked out and a subject onto itself. As the title suggests, this paper will focus on the prevention of the various problems encountered in FUT, rather than its treatment – an equally important subject, but one that has already been covered in an extensive review. [6, 7]
For those not familiar with Follicular Unit Transplantation, there is a concise review of the topic in the dermatology text Surgery of the Skin . For more detailed information, several hair transplant textbooks have sections devoted to this technique. [9, 10]
The most common types of problems that occur in FUT procedures can be grouped into two broad categories; those involving errors in planning the hair transplant and those caused by errors in surgical technique. Of the two, errors in planning often lead to far more serious consequences for the patient and will be the subject of this paper.
The single greatest mistake a doctor can make when treating a patient with hair loss is performing a hair transplant on a person that is too young. Although, there is no specific age that can serve as a cut off (since this will vary from person to person), understanding the problems associated with performing hair restoration in young persons can help the physician in deciding when surgery may be appropriate. Getting it wrong can literally ruin a young person’s life.
When someone is beginning to lose hair in their teens or early 20s, there is a significant chance that he (or she) may become extensively bald later in life and that the donor area may eventually thin and become see-through over time. Although miniaturization (decreased hair shaft diameter) in the donor area is an early sign that this may occur, and can be picked up using densitometry, these changes may not be apparent when a person is still young.
If a person were to become very bald (become a Norwood Class 6 or a Class 7) then he would often not have enough hair to cover his crown. A transplanted scalp with a thin or balding crown is a pattern acceptable for an adult, but totally unsuitable for a person in his twenties.  In addition, if the donor area were to thin over time, the donor scar might become visible if the hair were worn short – a style that is much more common in people who are young.
This subject is very closely related to age. For surgical hair restoration to be successful, expectations must match what can actually be accomplished. The expectations of a young person are usually to return to the look they had as a teenager; namely to have a broad, flat hairline and to have all of the density they had only a few years before.
The problem is that a hair transplant neither creates more hair (and therefore can’t increase overall density) nor prevents further hair loss (so the pattern must be appropriate as the person ages). But since receded temples and a thin crown is not an acceptable look for a young person, the surgery should best be postponed in a person in whom this is not acceptable. As a person ages, he often becomes more realistic and is happy with what a hair transplant can actually achieve. And, over time, if a person’s donor area proves to be stable and his hair loss limited, more ambitious goals can be attained.
Chronic Sun Exposure
Although it is common wisdom to avoid sunburns after a hair transplant, in fact, significant chronic sun exposure over one’s lifetime has a much more significant negative impact on the outcome of the hair transplant then peri-operative sun exposure.
Actinic damage alters the collagen and elastic fibers so that the grafts are not grasped as securely and the alteration to the vasculature decreases the ability of the recipient tissue to support the transplantation of a large number of grafts. Even with the very small recipient sites used in follicular unit transplantation, making sites too close can result in a compromised blood supply and result in poor growth.
Another issue is that a hair transplant will cover areas of sun damage and make cancer detection more difficult. When the actinic related growths are finally treated, the involved sections of the hair transplant will be destroyed.
The best approach in a person with significant sun damage is to first treat the entire scalp aggressively with 5-flurouracil to remove all of the pre-cancerous lesions before hair transplant is contemplated. One should wait at least 6-12 months after the treatment for the scalp to completely heal, as the tissue will be more friable during this period. Although this treatment can set the surgery back a year or more, it will result in better graft survival and less problems with future skin cancer detection.
Medical Conditions and Medications
Although not necessarily an absolute contraindication to surgery, a number of medical conditions make the follicular unit hair transplant procedure more problematic and need to be taken into account. Whenever significant medical conditions are present, it is always prudent to obtain medical clearance from the patient’s primary care physician or appropriate specialist.
Because the scalp is quite vascular, and FUT procedures involve a large surgical team, patients that are known to have blood born pathogens, such as HIV and Hepatitis B and C, pose some increased risk to the staff, despite the fact that universal precautions are used. It is useful if the team is aware of the medical histories of hair transplant patients so that they can proceed with a higher degree of alert when necessary.
In an HIV positive patient, it is important to make certain that the patient’s immune status is adequate, so that the patient does not have a greater risk of infection. In patient’s with Hepatitis, it is important to assess their liver function so that the dosing of medications is appropriate.
Patients with diabetes mellitus may be at greater risk of having a peri-operative infection. In this case the normal aseptic conditions that most hair transplants are performed under might be changed to a modified sterile technique (modified in that it is difficult to prep the scalp). This should also be considered in patients with cardiac valvular disease, implanted devices and others in whom bacterial seeding might have more severe consequences. Antibiotic coverage should also be administered in high risk individuals, although it is not needed in routine hair restoration procedures. 
A bleeding diathesis, significant enough to impact the surgery, can be generally picked up in the patient’s history; however medications often go under the radar and should be asked for specifically. Patient’s often don’t think to report taking aspirin and this must be asked about as well as other non-steroidal anti-inflammatory medications. Plavix, in particular can significantly increase bleeding during the procedure. Alcohol, of course increases bleeding as well. 
One should make adjustments in a patient’s anti-coagulant medication in conjunction with his/her cardiologist or regular physician. As a general rule, one should stop anti-platelet medications one week prior to the hair transplant, but the interval will vary depending upon the specific drug, the size of the procedure, and the importance of the medication to the patient’s health. They can be resumed three days after the procedure. If the anticoagulants cannot be stopped, it may be reasonable to proceed with a smaller session.
Since epinephrine is used in most hair restoration procedures, if a person has a history of arrhythmias or other cardiac disease that could be exacerbated by epinephrine, medical clearance from the patient’s primary care doctor, or cardiologist, should be obtained. Epinephrine can also interact with broad-beta blocking agents such as propranolol, causing a hypertensive crisis; therefore, it is best to have the patient switch to a selective beta-blocker for the surgery. 
A number of manipulations can be used during the procedure to control bleeding and decrease the need for epinephrine. Among the most useful, is to scatter the recipient sites broadly over the area to be transplanted (allowing the extrinsic pathway to begin coagulation) and then filling in the areas with additional sites when the bleeding has subsided. 
If patients have a history of seizures, it is important that they do not discontinue their medication for the procedure and that medical clearance is obtained. One should also remember that otherwise normal patients can have a vaso-vagal episode during the procedure; particularly during the administration of the local anesthetic. This can be avoided by immediately placing the patient in Trendelenberg as soon as the patient complains of nausea or begins to sweat, or look pale.
A patient should be monitored with a pulse oximiter if a significant amount of sedatives or other respiratory depressants are used. The patient should be monitored closely to be sure that local anesthetics are administered in safe amounts and that the warning signs of lidocaine overdose are well known to all members of the surgical team. 
Finally, it is helpful to have a pre-printed summary of all the medications and their doses commonly used during the procedure. This can be given to the patient’s regular physician when seeking medical clearance.
Hair loss can take a psychological toll on a person’s self-esteem and cause considerable emotional distress. When a person has underlying psychiatric issues, the impact can be more severe and, therefore, management of hair loss considerably more difficult. It is important to identify these problems as well as other psychological factors that may play a role in a patient’s ability to clearly understand both the hair restoration process and its anticipated outcome.
In some cases, counseling can be done in conjunction with hair restoration, but often it should precede treatment, especially when surgery is contemplated. It is prudent to obtain clearance for surgery from a psychiatrist or clinical psychologist when there is a history of mental illness, or when it is suspected at the time of the consultation.
A number of psychiatric conditions are particularly relevant to the successful outcome of a hair transplant. These include Trichotillomania, Obsessive-Compulsive Disorder (OCD), Body Dysmorphic Syndrome (BDS), and Depression.
Trichotillomania is a relatively common condition characterized by the persistent urge to pull out one’s hair. It most commonly involves scalp hair, but can also involve the eyelashes, facial hair or other body hair. It often results in bald patches and can be identified by short hairs in the affected area that are not long enough to grasp. Active trichitollomania on any part of the body is an obvious contraindication to a hair transplant, but if a person has a history of this condition, the doctor should also be cautious and only consider surgery if the therapist is confident that the condition has little chance of recurring.
Obsessive-compulsive disorder (OCD) is a condition characterized by recurrent, intrusive thoughts (obsessions) and related behaviors (compulsions) which attempt to neutralize the anxiety or stress caused by the obsessions. In consultation, the OCD patient often asks a litany of questions and often asks the next question before listening to the answer to previous one. OCD patients are extremely difficult to satisfy and even in a very successful hair transplant can focus on a minor imperfection seeming oblivious to the good overall result.
Body dysmorphic disorder (BDD) is a mental disorder that involves a distorted image of one’s body. The person is extremely critical of their physical self, despite the fact there may be no actual defect. It should be obvious that patients with BDD will not be satisfied with a hair transplant, or other forms of cosmetic procedures, and the condition is best treated by a psychiatrist rather than a surgeon. Another note of caution is that patients with BDD have a much higher suicide rate than the general population, even greater than patients with depression. 
Depression is possibly the most common psychiatric disorder encountered in patient’s seeking hair transplantation, but it is also a common symptom of those experiencing hair loss. The doctor must differentiate between a reasonable emotional response to balding and a depression that requires psychiatric counseling. It is important to realize that a hair transplant will be ineffective in curing a medical depression and unfulfilled expectations may lead to a worsening of the condition.
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