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What is PRP?

PRP stands for Platelet Rich Plasma. PRP provides a concentrated delivery of growth factors which may help to rejuvenate hair follicles. Activated PRP can increase the proliferation of dermal papilla cells and stimulate extra cellular signaling. This procedure may be effective in helping patients with hair loss – although clinical studies are limited and thus the results can not be assured. The procedure is very safe and there have been no negative side effects reported.

PRP is performed differently in different offices. In our office, local anesthesia is used to numb the area to be treated.  The platelet rich product is produced and combined with a product called ACell. This product has been used in reconstructive medicine in a variety of fields. Some doctors do not use any ACell with the PRP and others feel it acts to potentiate the results and provide a scaffolding to hold the PRP in the area for a longer period of time. We also perform a fairly aggressive microneedling prior to injection of the PRP. This signals the patient’s system to begin the healing cascade and also improves activation of the the growth factors in the PRP. Dr. Unger has found that patients can be treated twice with her technique after checking the platelet number. If the procedure is effective for the patient, the results last on average between 9-18 months. It is not a cure for hair loss – none exists at this time. However, it may be an effective treatment that does not involve daily use of medication and is an alternative option to try if other treatments have failed or produced undesirable side effects.

Platelet rich plasma (PRP) is a portion of blood that is rich in platelets and their various growth factors. The blood is drawn from one’s arm or hand, similar to the blood drawn for labs. The blood is processed in a centrifuge and after preparation it is injected in the body area of interest. PRP has shown beneficial in various medical conditions such as alleviating symptoms of osteoarthritis, bone fracture and wounds healing, various musculoskeletal injuries, skin rejuvenation and hair loss among others.

To Learn more about PRP click here.

Is The Use Of PRP Helpful?

Platelet rich plasma is being used now by some hair restoration surgeons, in a variety of ways including; injection into the scalp to help patients with chronic telogen effluvium, to help re-grow hair in men with androgenetic alopecia, as a holding solution for grafts while outside the body. In our office, we are currently studying the efficacy of the use of PRP. However, studies of this nature are exceptionally difficult to conduct. There are many confounding variables in the patient population, compliance in follow up is often inconsistent, and the manner of delivery of the PRP also varies. Dr Unger’s initial impressions thus far (still anecdotal) are that PRP may be most helpful in slowing the shedding of patients with chronic telogen effluvium, and may improve cell survival of the grafts while outside the body. For that reason, PRP is now being utilized as a graft holding solution for the majority of surgical patients. Other patients interested in enrolling in the study should contact Dr Unger’s office for an appointment.

Can PRP (Platelet Rich Plasma) treatment restore hair loss?

The answer to this question is somewhat complicated.  Briefly, PRP may be helpful, but there are limited clinical studies to determine how effective PRP can be in the treatment of hair loss. To make matters even less clear, one doctor’s PRP treatment may be very different from another doctor’s. Thus studies performed in different clinics cannot necessarily be compared to one another nor can the data be collated to provide a more complete picture.

Dr. Robin Unger has been using PRP in her practice for over 15 years. The technique and applications have evolved over that time. There are many patients who have seen regrowth of hair and a slowing of their loss. However, not everyone has positive results from PRP and there is no clear information to allow us to differentiate between those that are more or less likely to respond.  Our office in conjunction with Cornell is currently doing retrospective studies to try to further clarify the answer to this question.

Why PRP treatment needed only once – or twice?

A very frequent question I get in consultation is why my PRP treatment for hair loss is effective without doing it three or four times, as is commonly performed in most offices. To begin with, it is important to note that the answer to this question is not based on any clinical study with comparison of the results of different methods (such studies do not exist); rather it is based on my experience over the last fifteen years of treating patients with PRP. Most doctors who have started doing PRP for hair loss have only recently started doing so.


What Can Be Done To Minimize Any Scar In The Donor Area?

When performing a strip harvest, the surgeon needs to be certain to close without tension, bring the edges of skin together so they perfectly meet, and instruct the patient regarding post-operative care. Dr. Unger uses both “standard” and trichophytic closures. The latter provides the least visible scar, however there are some patients in whom a standard closure is preferable in the first surgeries. The scars are usually 1mm or less. FUE is an alternative approach discussed fully in the section on the donor harvest.

When Is The Right Time To Start With Hair Transplant Surgery?

Anwers to this question vary significantly between surgeons. Dr. Unger believes the patient is usually the best one to decide, and does not adhere to any doctrine limiting the age or stage of hair loss. The amount of existing hair is not important provided the hair transplant surgeon has the skill necessary to prevent permanent injury to this hair. Some individuals want to be very pro-active and either have an aversion to or have failed medical therapy: they may still have a significant amount of native hair but never want to go through a “bald” period. The patient may have hair loss unnoticeable except to themselves, or may have severe loss which has bothered them for quite a while. Other patients come to the decision to have surgery after all other attempts to address their hair loss have failed. The important caveat to clarify is that the surgeon must have a surgical plan which addresses current and future concerns – this is especially important when young patients are treated; the doctor needs to help the patient take a long-term view of their hair loss.

How Much “recovery” Time Does The Patient Need To Plan For?

Patients having this surgery for the first time should ideally take 7-10 days away from work and social activities if they want to keep the procedure confidential. In most cases, this amount of time is actually more than necessary. However, if you have planned to return to work after 3-4 days and you happen to be one of the patients with more swelling or bruising than the average patient, it can become a very akward situation. Usually, the first surgery is a good indicator of future healing, thus your schedule can be adjusted for subsequent surgeries. Obviously, patients with more pre-existing hair and those working posterior to the frontal hair line will have an easier time camouflaging the area during the post-operative period. A PDF of Dr. Unger’s post-operative directions is available on this website, and it may help answer further questions (although these are not uniformly followed by all doctors in the field).

How Many Surgeries Will Be Required?

This is one of the questions which can only be answered after a thorough examination with a hair restoration surgeon. The number of surgeries that will be required over the patient’s lifetime depends upon the age of onset of hair loss, the family history, and any underlying conditions. With respect to male patients, it also depends upon the surgeon philosophy with respect to treating only current areas of hair loss versus treatment of future areas of loss simultaneously. Therefore, one surgeon may say only one surgery is necessary: meaning the central region of frontal and midscalp hair loss can be treated in one surgery. In the future, that patient will undoubtably require a second surgery to treat areas which will develop with age. The benefit of this approach is that the patient’s immediate concerns are addressed. The drawback is that if the patient is unable to return in a timely fashion to treat evolving areas of loss, he will be left with a pattern of distribution of hair that does not occur in nature. Alternatively, a hair restoration surgeon may believe it preferable to complete the frontal area (current and future areas of hair loss) and subsequently repeat a similar process in the midscalp. This approach is beneficial because the patient is never left with an unnatural distribution of hair, and if for some reason is unable to return, he will not have a “strip” of hair down the middle with bald alleys on either side.

How Many “grafts” Do I Need ? What Are Megassion?

More is not always better – and in fact it may sometimes be worse. It is natural for patients to want to have as many grafts transplanted in one surgery as possible, however it is important that the pros and cons be carefully weighed. For purposes of this discussion, megasession will be defined as a surgery in which more than 2800 FU are transplanted (the definition varies greatly within the field). A detailed discussion of this topic can be found in many articles, however a brief summary may help to clarify some of the issues. The advantages of megasession potentially include 1) greater area of alopecia covered 2) possibly higher density achieved 3) fewer number of total surgeries. The disadvantages may include 1) larger strip harvest is more likely to lead to closure of the wound under tension and thus a wider donor area scar 2) greater time outside the body and hence potentially lower survival 3) a prolonged surgery and the concomittant exhaustion may increase error by the technicians or surgeon, leading again to decreased hair survival 4) greater injury to the blood supply with the large number of incisions in a relatively small area, once again threatening hair survival.

Each surgeon and each patient has to decide whether the potential risks of megasession are worth the benefits. Dr. Robin Unger does not promise a certain number of grafts per surgery, rather an approximate number is estimated after assessing the density and laxity of the donor area and deciding upon the surgical plan for the recipient area. The grafts may include follicular units consisting of 1-5 hairs, or double follicular units containing 4-8 hairs in appropriate patients. Average surgeries in female patients consist of 1000-2000 FU, while male patients with their longer and denser donor areas average 1800-2200. Dr. Unger believes that the blood supply in the recipient area becomes a significant concern if greater than 3000 sites are created in one surgery: this corresponds to approximately 12 feet of incisions in a very concentrated area (presuming the sites are approximately 1mm size).

What is A Cell?

Dr Unger has been using Acell in a variety of ways, for the last four years. Initially she tried using in the donor areas of patients who had developed bad scars from prior surgeons. Some of these scars were depressed and atrophic, as well as widened. With proper closure technique and the application of Acell, the scars and the texture of the tissue improved considerably. When tested on the donor areas of new patients with normal healing characteristics (one side with Acell and the other without), no significant benefit was noted. Although the sample size was small (10), Dr Unger was left with the impression, that Acell in the donor area is most useful in patients with pre-existing poor scars. Dr Unger feels it is most useful when combined with the PRP as a holding solution for the grafts. For the last six months she has done this fairly consistently, and although not ready yet for publication, her strong impression is that the Acell considerably hastens the re-growth of grafts – many of the transplanted hairs actually never undergo effluvium. Although Dr Unger is still unable to present the facts in a scientific paper, she feels that this technology has significantly improved the preservation of cells while outside the body. It remains a clinical investigation and therefore participation is voluntary, at no cost to the patient.

What is Liposomal ATP?

Theoretically, liposomal ATP is believed to accelerate the uptake of oxygen by cells. As applied to hair transplantation, this may improve the speed of healing and produce higher rates of survival. Dr Jerry Cooley has been at the forefront of this research, and he has determined that the optimal use for this product is at a specific concentration to be sprayed on the recipient area every two hours for the first 48 hours and then every 3-4 hours. Thus it is fairly labor intensive for the patient. We are just starting to treat patients with the liposomal ATP and we will carefully document results at 2 month intervals.

How Should I Choose My Hair Transplant Surgeon?

Firstly, DO NOT base your decision on anything you read on the internet. The internet can be a wonderful source of information, but can also be very misleading and/or function as an advertising tool for a particular doctor. Ask your primary care doctor, dermatologist, plastic surgeon, hair stylist, and friends. Speak to people who have seen the actual results from the particular surgeon (and not just those specially chosen by the doctor as “good examples”). Go meet the hair transplant surgeon in consultation in person if at all possible – different doctors may have an approach or style that matches more or less closely to your needs. Ask to see photos of their work and ask how they are specifically trained in this field: hair transplant surgery requires very specialized training and is not “officially” part of most residency programs. A fellowship and/or American Board of Hair Restoration Certification are the best available means to ensure the doctor is qualified. This is a very important decision which will have permanent consequences for your life, so take time, meet several doctors for whom you received recommendations and meet more if necessary until you find the right match for you.

What Are The Benefits And Disadvantages Of Fue (Follicular Unit Extraction)?

Dr Unger believes that every good hair restoration surgeon should have the knowledge to use all the “tools in her toolbox” – and this includes FUE. Patients that may be appropriate for FUE include those who want to wear their hair exceptionally short, those with very tight scalps, patients who have bad scars from previous strip excisions, and patients with inexplicable fear. Otherwise, the best use for FUE is after elliptical harvests have been maximized; FUE can help slightly expand the available donor hair and can also be used to camouflage even good linear scars. This harvest method is being very broadly marketed throughout the world as the “newest technique”. It is in fact a variation on the old technique of utilizing punches to extract grafts from the donor area. The new punches are smaller (0.9-1.2mm) and the grafts they retrieve are likewise smaller follicular unit grafts. Each site where the graft is removed is left to heal by secondary intention, forming a small circular scar. These scars are obviously much less evident that those created by the 4.0mm or 2.0mm punches – but instead of hundreds of larger scars being created, thousands of smaller ones are left after FUE. When the patient is still young, these are not particularly problematic, however as the patient ages and the donor rim hair thins, the impact on the density becomes more significant. Furthermore, because only every 3-4 follicular units can be harvested with FUE, it is tempting to expand the size of the donor area to include more hair – however some of this hair will be outside the safe donor rim. Those hairs which have been transplanted will be lost over time (in a dispersion that is not controlled) and the small scars may become fully visible in the alopecic areas.

Are Women Good Candidates For Hair Transplant Surgery?

Female hair transplantation is an exceptionally successful procedure if the treatment area is carefully chosen and the technique is meticulous. Approximately 40% of Dr. Robin Unger’s practice consists of female patients – and the impact on their life is of great significance. Female hair loss is very distressing, regardless of the age at which it occurs, and unfortunately, there are few options available that will actually re-grow hair. The hair transplant is performed in the area which will produce the greatest cosmetic benefit, and the grafts are placed between the pre-existing hairs. Great care is taken to protect this native hair and in a recent survey, her patients reported that the increase in density met or exceeded their expectations in 97% after one surgery. For more information please see the description under general procedural details.

During menopause do women lose hair?

Yes! Every woman (every!!) will experience a more rapid rate of hair shedding during the peri-menopausal period. When woman are in complete menopause and without hormone replacement they will lose hair at a more rapid rate than prior to the menopausal period. Hair loss can be significantly influenced by the ratio of androgens to estrogens. Depending on how thin a woman’s hair is at the start of the process, this increased loss may become very significant. An earnest conversation with your gynecologist or endocrinologist may help determine whether hormone replacement therapy or anti-androgen treatments may be helpful in slowing the rate of hair loss.

Does hair transplant surgery work for women?

Hair transplant surgery always works if performed properly AND the potential results are well matched with the patient’s expectations. The main premise behind this is that of “donor dominance”. When hair is transplanted from the relatively permanent donor rim of hair to an area more significantly affected by hair loss, the transplanted hair retains the same characteristics as the relatively permanent rim hair. Thus, if a patient and the doctor discuss the areas of greatest cosmetic concern and there is sufficient donor hair to treat that region, the patient will have a significant increase in density that is long lasting – in the area of greatest importance. Many times doctors tell female patients they are not good candidates or their donor hair is insufficient. This is only true if the doctor believes that he/she needs to treat all the areas of alopecia. In many cases, women have very good styling options provided that certain key regions are transplanted to achieve higher hair density. In addition, many surgeons today are accustomed to treating largely bald areas or those that they can shave. This renders them reluctant to treat women with long hair present in their areas of thinning. It is important to seek out a surgeon with a significant amount of experience in treating patients who still have a significant amount of pre-existing hair.

Does hair transplant surgery hurt?

Most patients find the hair transplant very easily tolerated. It hurts approximately the same as a dental procedure. However, patients have different levels of tolerance for pain (and pain medication) – thus it is difficult to say “yes” or “no”. Most patients report that the procedure is mildly uncomfortable. The initial injections to numb the surgical areas do sting a little. The numbing medication usually last the entire day or is reinforced at intervals to maintain complete anesthesia. Each office is different in terms of the level of anesthesia they can provide. Our office is certified by the Joint Commission and thus we regularly administer light sedation for our patients over the day. We also provide intravenous analgesia (pain control) that lasts through the post-operative period. We dispense pain medication to all our patients at the end of the day. These are taken as needed – and as previously mentioned, some patients need this medication while others are quite comfortable with Tylenol.

Overall patients do find the sutures after a strip harvest more uncomfortable than the generalized “razor burn” sensation after an FUE procedure. Neither procedure is pain-free. We do our very best to provide our patients with excellent pain control measures and virtually every patient is surprised at the ease with which they tolerate the surgery.

How long do the results from hair transplant surgery last?

This question is very important to clarify. The results from a hair transplant are long lasting. The patient, over their lifetime, will always have more hair than they otherwise would have had. That being said, the pre-existing hair in the region will continue to thin and – at a much slower rate – so will the transplanted hair. The hair that is transplanted is taken from a region of the scalp much less affected by the process of androgenetic hair loss. Thus those hairs will shed at a rate much slower than those naturally occurring in the affected region. This is the main reason why hair transplants have been effective in treating androgenetic hair loss. It is important to try to slow this future loss with adjuvant therapy, which may include medical therapy, hormone therapy or PRP.

Does biotin work for hair loss and should everyone take it?

Biotin (also known as vitamin B7) is a water-soluble vitamin and an essential component of several metabolic processes in the body. More specifically, biotin plays a role in gluconeogenesis (generation of glucose from non-carbohydrate carbon substrates and one of the two main mechanisms that we use to keep our blood glucose levels from dropping too low), fatty acid synthesis (important for cell growth, differentiation, and homoeostasis), and amino acid catabolism (to synthesize new amino acids, or to be used for energy).

If I take biotin, will it help my hair loss? For other FAQ's click here.

Does The Hair Transplant Always “work”?


Yes. When a hair transplant is performed carefully and with attention to detail, the surgery increases the density of hair in the area treated. Hair is removed from the permanent donor area and moved to an area with hair loss. The transplanted hair will behave in this new region, as it would have in its original location. To be clear, this hair is “relatively permanent” in that it will gradually thin as a person ages, but will not disappear completely. Thus, the effects of the hair transplant are long lasting.

Of course, there are situations that can result in an unsuccessful transplant: poor planning by the surgeon with respect to the blood supply and density of sites, poor dissection technique by technicians, sub-optimal storage of the grafts outside the body and/or traumatic graft placement. Modern transplant surgery utilizes very small grafts, which are especially vulnerable. Therefore it is particularly important to be certain that the surgeon performing the hair transplant is well-trained and has a similarly excellent staff of technicians, who have the training and time to prepare and place the grafts with the utmost care.

Dr. Robin Unger

Dr. Robin Unger710 Park Avenue, Suite 1ANew YorkNY, 10021
Main: (212) 249-4369
Fax: (212) 249-4032

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