Follicular Units in Hair Transplantation: The Days of Plugs are Gone

Follicular units in Hair Transplantation

Close of view of 'follicular units' two weeks after a hair transplant. In a week or two, these hairs will fall out and reemerge in 2-3 months. 

What are "follicular units"?

The buzz word of modern hair restoration is the 'follicular unit'. No longer do hair transplant surgeons move "plugs" of hair into balding areas. Nowadays, we move 'follicular units.'

The photo on the right shows a number of follicular units packed into an area of hair loss. The actual area measures less than 1 cm x 1 cm. The photo was taken two weeks after the hair transplant was performed. What you can see is the groupings of these follicular units. Many of the follicular units are two haired grafts, and some are even three haired grafts. These are the natural groupings of hairs in the scalp. By moving follicular units rather than plugs, a very natural look can be obtained. 

After a hair transplant,  follicular units develop crusts and fall out. They leave behind the root deep beneath the skin - and three months later a brand new hair is produced.

PRP for Hair Loss: Another Study Points to Benefits

PRP for Hair Loss: One More Study to Add to the List

PRP for Hair Loss

Platelet rich plasma or "PRP" for hair loss refers to the injection of a patient's platelets into the scalp in attempt to stimulate hair growth. In order to perform PRP, a small amount of a patients blood is taken (similar to getting a blood test done), and the blood is processed in a PRP machine in order to isolate the platelets.

A number of recent publications support the role of PRP in the treatment of genetic hair loss. In addition, some authors  showed that pretreatment of follicular units with PRP before transplantation resulted in improved hair growth and density.

In a new study, published in the journal Biomedical Research International, researchers from Italy performed a study in 10 men. One side of the scalp was treated with platelet rich plasma and the other side was treated with placebo (saline). Results were compared at 14 weeks, 6 months and 1 year. 

What are the results?

The results of the study showed a significant increase in hair count for the treatment area after just 3 months. There was an increase total hair density of 27.7 hairs per  square cm compared to baseline.  In addition, terminal hair density improved significantly by 27.0 ± 15.3 (number of hairs/cm2) in the treatment area, while decreasing by 2.1 ± 12.4   in the control area of the scalp.

Conclusion

We are no longer in the era where we "wonder" if PRP works to help those with hair loss. Rather we have moved into the era where we know if helps and now need to determine what is the best way to perform PRP.

What is the best machines to use to prepare PRP (what machine should physicians buy)?

What is the optimal amount of PRP to inject (is too much going to be bad)? 

What is the optimal frequency to repeat PRP injections for those with hair loss (1 month 4 months, 6 months)?

However, this Italian study adds to a growing list of studies showing that PRP is a bonafide treatment for hair loss.  

References

Cervelli et al. The Effect of Autologous Activated Platelet Rich Plasma (AA-PRP) Injection on Pattern Hair Loss: Clinical and Histomorphometric Evaluation. Biomed Res Int. 2014; 2014: 7  

 

Other References:

1. Takikawa M, Nakamura S, Nakamura S, et al. Enhanced effect of platelet-rich plasma containing a new carrier on hair growth. Dermatologic Surgery. 2011;37(12):1721–1729. [PubMed]

2. Li ZJ, Choi H-I, Choi D-K, et al. Autologous platelet-rich plasma: a potential therapeutic tool for promoting hair growth. Dermatologic Surgery. 2012;38(7, part 11):1040–1046. [PubMed]

3. Uebel CO, da Silva JB, Cantarelli D, Martins P. The role of platelet plasma growth factors in male pattern baldness surgery. Plastic and Reconstructive Surgery. 2006;118(6):1458–1466. [PubMed]

4. Trink A, Sorbellini E, Bezzola P, et al. A randomized, double-blind, placebo- and active-controlled, half-head study to evaluate the effects of platelet-rich plasma on alopecia areata. British Journal of Dermatology. 2013;169(3):690–694. [PubMed]

Minoxidil - How long should I leave it on?

Minoxidil - what's the minimum time to leave it on and still work?

Minoxidil has been in the market for about 25 years, receiving FDA approval in 1988. Many people recognize one of the popular brand names - Rogaine. Minoxidil is approved male pattern balding (androgenetic alopecia) as well as female pattern hair loss. It can also be used to treat several other conditions. In women, minoxidil can be used before and after a hair transplant to reduce the chances of post operative shedding. Some patients also use minoxidil after a transplant to speed up the rate of growth of the grafts.

How long should I leave the minoxidil on the scalp?

A common question I'm asked is how long to leave the minoxidil on the scalp. Ideally it is left on for 8 hours but the 'minimum' time I advise is 4-6 hours. After 4 hours, 75 % of the minoxidil is absorbed.

This advice comes from a 1990 study. In that study, twenty-two healthy male volunteers completed a four-way, multiple-dose, randomized crossover study to determine the relationship between contact time of applied drug on the scalp and minoxidil absorption from a 2% topical solution.  The researchers examined how much minoxidil is absorbed at 1 hr, 4 hr compared to 11.5 hours. Relative to the amount absorbed after a contact time of 11.5 h, absorption was approximately 50% complete by 1 h and greater than 75% complete by 4 h.

Conclusion:

Although minoxidil should ideally be left on 8 hours, tremendous benefit can still be achieved with 4 hour use. Understanding the absorption of minoxidil is important to help improve the ability of patients to 'stick with' the treatment. 

Reference

Ferry JJ et al. Relationship between contact time of applied dose and percutaneous absorption of minoxidil from a topical solution. J Pharm Sci. 1990 Jun;79(6):483-6.

Follicular Unit Extraction (FUE) for Grey/White Hair

FUE for Grey/White Hair

Follicular unit extraction (FUE) is a method of removing hair from the back of the scalp ('donor area') one by one. It is often considered in men who wish to wear their hair short because it does not create a linear scar.  By linear scar, I simply mean a scar that appears as a thin thin.

FUE is more challenging in patients with certain hair characteristics, including those with very curly hair and those with grey/white hair. However, with careful planning, their are ways to overcome these challenges.

1. FUE for Curly Hair (Black men and women).

A previous blog I wrote last year discussed ways of successfully performing FUE for black men and women.

2. FUE for Grey/White Hair

FUE is more challenging in those with grey white hair because it is more challenging to see the angle of the hairs beneath the scalp.  Theoretically, if the angle can not be properly seen, the rate of injury or transection goes up considerably.  We encourage our FUE patients with grey/white hair to dye their hair 4 days before the procedure and to wash the scalp daily in the days leading up to the procedure. This allows us to visualize the hairs more effectively and reduce transection rates during FUE extraction.

Comment:

Contrary to popular views, FUE is not for everyone.  However, with careful planning and design of the procedure, a large number of patients who might otherwise be considered poor candidates for FUE can be offered the procedure.

Minoxidil for Eyebrows: Worth Considering Before Eyebrow Transplantation

Thinning Eyebrows: Hair Transplant vs Minoxidil

Thin eyebrows are common and we're seeing more and more patients (both men and women) who are looking to enhance their eyebrows. For some of my patients, it's clear that eyebrow transplants are the only method to restore the density they are looking for.  For other patients, a trial of topical minoxidil is worthwhile before considering a hair transplant.

Minoxidil for eyebrows: New study suggests benefit

Topical minoxidil can be applied to enhance eyebrows. Until recently, there was no good study comparing minoxidil lotion with placebo for eyebrow enhancement. Researchers from Japan determined the efficacy and safety of minoxidil 2% lotion for eyebrow enhancement compared with placebo. 40 patients were randomized for minoxidil on the eyebrow on one side of the face and placebo on the other. Efficacy was evaluated by photographs, measurement of eyebrow diameter, eyebrow count and the satisfaction of study participants. Side-effects were also evaluated.

What were the results of the study?

Thirty-nine patients (97.5%) completed the study. After 16 weeks, the minoxidil group achieved significantly better results in all measured outcomes compared to the placebo group. Side-effects were minor and did not preclude patients from continuing the study. The conclusion of the study was that minoxidil 2% lotion is a safe and effective treatment for individuals with age related or genetically thin eyebrows.

Reference of Interest

Lee S et al. Minoxidil 2% lotion for eyebrow enhancement: a randomized, double-blind, placebo-controlled, spilt-face comparative study. J Dermatol. 2014 Feb;41(2):149-52. 

 

Scalp Dermoscopy

Scalp Dermoscopy.

A "dermatoscope" is a hand held device that uses magnification, and a transiluminating source (sometimes with polarized light) to better evaluate hair loss patterns. I have several types of dermatoscopes. Most images here in my blog have been shot with a device known as Dermlite Pro HRII or Dermlite DL. A dermatoscope is essential to the proper evaluation of hair loss.

Can men use dutasteride and finasteride together?

Finasteride is formally FDA approved for the treatment of male balding. While not formally FDA approved, dutasteride can be used off label in the treatment of male balding or 'androgenetic alopecia'. Both drugs can be used alone or with other therapies such as hair transplantation, minoxidil and platelet rich plasma. 

Finasateride is an inhibitor of the enzyme 5 alpha reductase type 2  and dutaseride is an inhibitor of both 5 alpha reductease type 1 and type 2. Dutasteride is more potent and leads to greater reductions of dihydrotestosterone (DHT). Side effects are also greater.

Patients who have a partial response to finasteride often wonder if they should switch to dutaseteride or add dutasteride. Adding a very small dose of once weekly dutasteride can often be a good option. An Australian study in 2013 reported a 47-year-old man who was initially treated with finasteride for male pattern balding. Despite continuous treatment, after year 4 his hair density was not as good as previous years, and low-dose dutasteride at 0.5 mg once per week was added to the finasteride therapy. Interestingly, this resulted in a dramatic increase in his hair density, demonstrating that combined therapy with finasteride and dutasteride can improve hair density in patients already taking finasteride.

Comment

This study shows how careful planning of safe medical treatments can lead to improvements in patient's outcomes.

Reference

Boyapati A and Sinclair R. Combination therapy with finasteride and low-dose dutasteride in the treatment of androgenetic alopecia. Australas J Dermatol. 2013 Feb;54(1):49-51.  

 

Topical ketoconazole shampoos: Are they helpful for hair loss?

Ketocaonzole shampoos promotes hair growth

Ketocaonzole is a an antifungal agent and effective for the treatment of seborrheic dermatitis and "dandruff". But research over the past many years has suggested that they help hair loss as well. I often recommend that individuals with genetic hair loss consider use of anti-inflammatory shampoos.

What were the results of ketoconazole studies for hair loss?

A 21 month study  compared the use of topical minoxidil to ketoconazole 2 % shampoo. Study participants received the 2 % shampoo or an unmedicated shampoo with or without minoxidil 2 %. Interestingly, hair density and follicle size improvements were similar with both ketoconazole and minoxidil regimens.

How do ketoconazole shampoos help hair loss?

The mechanism by which topical ketoconazole improves hair density and hair growth is unclear, but may be due to is anti-inflammatory effects against T cells and the yeast of the scalp which create inflammation (Malassezia yeast). Ketoconaozle also inhibits steroidogenesis and decreases DHT levels.

References

Inui.  J dermatol Sci 2007; 45: 66-8.

Pierar Franchimont Dermatology 1998; 196: 474-7

Achieving density in hair transplants: does FUE, Artas or strip make a difference?

One question I'm often asked is robotic FUE can lead to more dense hair transplant results compared to manual FUE or follicular unit strip surgery (FUSS).

The type of donor area extraction technique does not impact the density of hair transplant results. The only factor that influences the density of the hair transplant is how the hair restoration specialist creates the recipient sites. If the sites are made at 30 FU per cm2 the results will be more dense than if made with 20 FU per cm2.

ARTAS, manual FUE and strip are all techniques to get the hairs out - the artistry and talent of hair restoration is determined by how they are put back in.

How much better is 5 % minoxidil than 2 % minoxidil ?

Both 5 % and 2 % minoxidil are available for treating genetic hair loss. The 2 % minoxidil was initially FDA approved in 1988 for male balding and this was followed by approval of the 5 % minoxidil for male pattern hair loss in 1997.

For men, the initial clinical studies showed that 5 % minoxidil was more effective than the 2 % minoxidil. 60 % of men have some benefit from the 5 % compared to just 40 % with the 2 % minoxidil. 23 % of men using the placebo in these studies also had benefit.

For women, clinical studies suggest 5 % and 2 % minoxidil have similar efficacy. The 5 % formulation is now formally FDA approved for use by women.

Understanding Color Contrast in Hair Transplant Surgery

The Role of Color Contrast: 

The key to a great hair transplant is understanding the aesthetics of angles, proportions, direction, density --- and also "optics." The way that light is reflected from the scalp affects how an onlooker views the density of one's hair.

The basic principle of 'optics' in hair transplant is as follows:

The less contrast there is between the color of a patient's skin and the color of their hair, the easier it is to create a perception of naturalness. 

Therefore creation of an appearance of naturalness is easier for patients with light-colored skin and moderate thickness blonde, grey or salt-and-pepper hair. The same is true for individuals with darker skin and darker hair. Careful planning is needed for those with light skin and dark hair (or dark skin and light hair) to ensure a great result.

Strip vs FUE in hair transplantation: What was more commonly performed in 2013?

Follicular Unit Strip surgery more common in 2013

In 2013, strip surgery remained more popular than follicular unit extraction according to the 2013 ISHRS Practice Census Survey

It comes as a surprise to many that strip surgery was more commonly performed than follicular unit extraction (FUE). A 2013 survey of over 900 hair transplant surgeon members of the International Society of Hair Restoration Surgery (ISHRS) showed that about 67 % of procedures were performed using strip surgery (FUSS) and 1/3 were by follicular unit extraction (FUE).

At Donovan Medical, both types of procedures are performed. Some individuals may be better candidates for FUE than strip and other individuals may be better candidates for strip than FUE.

Source:

International Society of Hair Restoration Surgery (ISHRS) - 2013 Practice Census Survey.

22nd Annual International Hair Transplant Surgery Meeting Announced

Hair Transplant Surgery Meeting Set for Kuala Lumpur 

Great news that the 22nd Annual Scientific Meeting of the International Society of Hair Restoration Surgery is set for Oct 8-11 in Kuala Lumpur, Malaysia. Looking forward to another great meeting!

The International Society of Hair Restoration Surgery (ISHRS)

The ISHRS is the leading authority on hair loss treatment and restoration with more than 1,000 members throughout 60 countries worldwide. 

Achieving appropriate densities in hair transplantation

The density of follicular units can be calculated by dividing the number of grafts placed in an area by the area. This patient with extensive thinning was transplanted at a density of 32 follicular units per square cm (32 FU/cm2).

What densities do we aim for in hair transplantation?

One of the most important parts of the hair transplant surgery is determining how close to place or 'pack' the grafts. A patient with a large area of hair loss to fill (such as a Norwood VI) with limited donor supply may want to use 3000  grafts at a density of 30-35 follicular units per square cm. Another individual with limited hair loss in the frontal scalp may want to use 1000 plus hairs packed at a density of 35-45 follicular units per square cm

 

 

Different follicular unit densities for different patients and different areas of the scalp

The frontal hairline is an area where decisions on target density are very important. A density of 40-45 follicular units per square cm was planned for this patient.

The density that is chosen for each patient requires careful thought. A patient with course curly grey-white hair will require less grafts for than a patient with fine straight blonde hair. A density of 30-35 FU/cm2 might be chosen for the grey haired patient whereas a target of 40 FU/cm2 or more may be required for the patient with fine hair.

In addition, different areas of the scalp often require different densities to achieve a good result. The frontal hairline might require 40 FU/cm2 to 50 FU/cm2 depending on the patient.

It's extremely important to think about the density of recipient sites in hair transplant surgery There is not magic formula or recipe - and each patient's procedure needs to be carefully considered and planned. 

The Phototrichogram: A Powerful Tool in Assessing Hair Loss and Growth

The phototrichogram helps assess hair growth patterns & treatment responses

The phototrichogram is a clinical tool I generally only use in my research - when I want to understand if a specific treatment is helping or not and quantify just 'how much' it helps. However, sometimes I will use the phototrichogram in patients with complex hair loss patterns. The phototrichogram involves comparison of two small 1 cm x 1 cm areas on the scalp at an interval of three days.  On day 1, the hairs in the target 1 cm2 area are clipped to 1 mm and a photograph is taken. 2-3 days later the same areas is evaluated again

What information comes from the phototrichogram?

Several key pieces of information come from the phototrichogram. Hairs that grow over the 2-3 day period are deemed 'anagen' hairs. Hairs that don't grow or elongate are deemed 'telogen' hairs. Hairs that are not present at day 1 but present at day 2-3 are deemed anagen hairs. In addition, hair calibre can also be ascertained. Hairs greater than 40 um are terminal hairs.

Figure 1. The Phototrichogram. Hairs that do not elongate over a three day period are telogen hairs. The blue circle shows a telogen hair. The green circle shows one telogen hair and one anagen hair. The red circle shows a significant increase in hairs. Hairs that were not present at day 1 but present at day 3 are anagen hairs. 

In general, the following information can be ascertained from a carefully conduced phototrichogram:

1. hair density

2 terminal hair density

3. vellus hair density

4. anagen hair counts

5. telogen hair counts

6. mean hair thickness

Conclusion

The phototrichogram is a powerful tool. It's not routinely employed in the clinical setting because most patients don't want their hairs clipped (patients come to see me for help with more hair - not less).  Nevertheless, the phototrichogram remains a tool I call upon from time to time 

What is the risk of balding if my father has hair loss?

What is the risk of developing male pattern balding if my father has hair loss?

It's challenging to 100 % predict any man's exact chances of balding. The genes for hair loss come from mom's side and dad's side and dozens of genes contribute to one's chances to develop hair loss. 

I'd like to tell you about two studies I often share with my patient's when they ask me about their chances of balding

Two Important Male Balding Research Studies

In a study of 572 men ages 16-91, young men with a balding father had a 5.5 times increased risk of balding than young men who did not have a balding father.

In another study, only 1 of the sons of 50 non balding men had Hamilton Norwood type III balding or worse. In contrast, 32 of 54 (60 %) of sons whose fathers were bald had Hamilton Norwood scale type III baldness or greater 

Having a father with balding greatly increases the chance a male with develop male pattern baldness or MPB.

References

Birch  MP Eur J Dermatol 2001; 11-16

Ellis JA. J Inv Dermatol 1998 110: 849-53

To caffeinate or not to caffeinate: What is the benefit of caffeine shampoos in men?

Are Caffeine Shampoos Helpful for Hair Loss?

This was a great week for discussions with my hair transplant patients about caffeinated shampoos.  Do they work?  What is the evidence? I thought this would be a good time to review this interesting topic. Previous studies have shown that caffeine can inhibit the negative effects of testosterone in a laboratory setting (i.e. in a petrie dish). How exactly it does this remains to be clarified, but caffeine is known to have many effects including blocking the cell death that occurs with androgenetic alopecia.

One of the best studies to date looking at the role of caffeinated shampoos was a study by Sisto et al and published in the Journal of Applied Cosmetology in 2013.

2013 Study of Caffeine Shampoos

Sisto et al from Italy set out to look at the benefit of a caffeine shampoo using a randomized controlled, double-blind study in 66 men with genetic hair loss. 33 received the test shampoo and 33 received the 'placebo' shampoo not containing caffeine. These two groups were matched to ensure that they were similar ages and had similar degrees of balding.

What were the results of the study?

Men using the caffeinated shampoo for 6 months were more satisfied with their outcome than men using the placebo (84.8 % vs 36.4 %, p<0.001). Men using the test shampoo were significantly more likely to feel that their hair loss had improved and were significantly more likely to report and improvement in strength and thickness of their hair.

Conclusions

This study supports a mildly beneficial effect of caffeinated shampoos. One of the limitations of the study is that it is predominantly survey based and the researchers relied on subject responses to survey questions to determine if a benefit present. Further studies are needed to quantify the benefit of caffeinated shampoos more precisely. However, this study does lend support to the notion that caffeinated shampoos may improvement the strength of hair follicles and slow the rate of balding.

Reference

Efficacy of a Cosmetic Caffeine Shampoo in Androgenetic Aloepcia Management. J Appl Cosmetol 2013;

Fischer TW et al. Effect of caffeine and testosterone on the proliferation of human hair follicles in vitro. Int J Dermatol 2007; 46: 27-35.

Is genetic hair loss in women the same as in men?

Genetic hair loss in women: Is it the same as in men?

I'm not asked this question very often by patients, but it's a question that I think about nearly every day. Genetic hair loss in women is not the same as genetic hair loss in men. In fact, most hair specialists, including myself, steer away from using the term "androgenetic alopecia" for women and use the term "female pattern hair loss (FPHL) instead.

 

FPHL vs male AGA: A few of the important differences:

1. In men, androgen hormones are essential in driving the process of baldness.  Without androgens there is no baldness. This is not quite so clear cut in women and blocking androgen hormones doesn't always have a benefit. In fact, increasing androgen hormones may actually help some women.

2. The genetics of hair loss in women is more complicated as well. A proportion of women develop genetic hair loss without strong family histories

3. Alterations in estrogen signalling may have an important role in FPHL.

4. In men with AGA, the drug finasteride seems to be more effective in those men with specific findings in the androgen receptor gene (i.e. shorter CAG repeats of the AR gene).  In women with FPHL, the efficacy of finasteride can’t be predicted with the same degree of certainty.

5. The patterns of hair loss are different as well with women losing hair in the central scalp and men losing hair in the temples and crown. 

6. A much lower proportion of women are good candidates for hair transplant surgery on account of genetic hair loss affecting the donor area.

7. Females have 3 to 3.5 times less 5 alpha reductase than men 

8. Female have higher aromatase levels than men. This enzyme converts testosterone to estradiol and estrone which reduces the conversion to DHT. The levels of aromatase are 6 times higher in the frontal hairlines of women than men. These differences in aromatase may explain why retention of the frontal hairline is a typical feature of FPHL but not male balding

9. Furthermore, even though androgen receptor levels are greater in the frontal scalp than the occipital scalp in both men and women, the total receptor level is 40 % less in women.

10.  The above points 7-9 may explain why the oral medication finasteride does not help as many women as it does men.

References

Conclusion

It's a mistake to think of FPHL as simply the female equivalent of male balding. 

References

Sawaya et al J Inv Dermatol 1997; 109: 296-300

Does FUE leave a scar? Does ARTAS leave a scar? OF COURSE!

Hair transplants with FUE and ARTAS: Does it leave a scar? 

One of the biggest sources of confusion in the public is that hair transplants done via follicular unit extraction or "FUE" is a scarless procedure. This is wrong. 100 % wrong.  Any time an incision is made in the skin, below a certain level, a scar wants to form.  There is no changing the laws of nature. We have to deal with the laws of nature and work around them. Such is life.

FUE leads to small circular micro scars.

Yes, FUE leads to small circular micro scars. Any form of FUE, whether robotic FUE with ARTAS or manual FUE or motorized FUE or Neograft. They all lead to tiny circular scars. There is a lot of interesting research going on to try to figure out how to reduce the appearance of these scars -  but scars do form. 

Fortunately, or unfortunately, there is no changing the laws of nature. We have to deal with the laws and work around them.  Anytime an incision is made into the skin, a scar wants to form. In 2014, a scar does form. Someday we might be able to block this process of scarring or reduce the formation of a scar, but not right now.  FUE is not a scar-less procedure.

New study of HairMax LaserComb shows benefit in men and women

Men and women benefit from HairMax LaserComb according to new research study 

As my patients know, I'm a stickler for good scientific evidence and data on hair loss treatments. If I'm going to recommend a treatment, there has to be evidence it helps. Why would anyone want to spend time or money on a useless treatment?

There has been emerging data over the past years on the potential benefits of low level laser therapy (LLLT). A number of LLLT devices are on the market now and are being used in patients with hair loss and in some patients after hair transplants. Few LLLT devices have been subjected to rigorous testing.

What is considered rigorous testing for LLLT?

A good scientific study involves testing of a drug or product in a randomized, double-blind manner and multiple different centers. Randomized means that some patients would receive the real medication or treatment device and some would receive a placebo or 'fake' treatment. Double-blind means that both patients and doctors don't know who is getting the real treatment and who is getting the placebo.

So, are there any randomized, double blind multi-center studies of any low level laser therapies? 

Fortunately, there is ! I was pretty excited to share with my patients this past week a new study published in the American Journal of Clinical Dermatology last month. The study was a randomized, sham device-controlled, double-blind clinical trials conducted at multiple US centres.

How was the LLLT study designed?

Investigators set out to determine whether treatment with the HairMax Lasercomb® was helpful for men and women with pattern hair loss. A total of  128 male and 141 female subjects were randomized to receive either a lasercomb (one of three models) or a sham device in concealed sealed packets, and were treated on the whole scalp three times a week for 26 weeks. Terminal hair density of the target area was evaluated at baseline and at 16- and 26-week follow-ups, and analyzed to determine whether the hypothesis formulated prior to data collection, that lasercomb treatment would increase terminal hair density, was correct. 

What were the results?

The HairMax LaserComb was found to increase in terminal hair density and this was independent of the age and sex of the subject. Additionally, a higher percentage of lasercomb-treated subjects reported overall improvement of hair loss condition and thickness and fullness of hair in self-assessment, compared with sham-treated subjects. No serious adverse events were reported in any subject receiving the lasercomb in any of the four trials.

Conclusion

The key limitation in LLLT becoming more accepted in the world of hair loss is solid scientific data. This is one of the first high quality independent multi centre studies in LLLT done.  These results suggest that the HairMax LaserComb low-level laser treatment may be an effective option to treat pattern hair loss in both men and women.   

 

Reference

Jimenez JJ, Wikramanayake TC, Bergfeld W, Hordinsky M, Hickman JG, Hamblin MR, Schachner LA.  Efficacy and Safety of a Low-level Laser Device in the Treatment of Male and Female Pattern Hair Loss: A Multicenter, Randomized, Sham Device-controlled, Double-blind Study. Am J Clin Derm 2014 Jan 29.