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Dr. Bertram Medical Hair Transplant
眉 髮 醫 學 移 植 中 心 ( 香 港 ) |
( 852 ) 3421-1138
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Research 3 - Hair Loss in the Donor Area After Hair Transplant
The result of this study was presented in the 2008 ISHRS Annual Scientific Meeting in Montreal, Canada. It was subsequently published in International Forum ( March/April 2009 Volume 19, No. 2 ).
Introduction
When patients come for hair restoration surgery, the last thing they want is to lose more hair. Yet this can occur post-operatively, both in the recipient and donor areas.
In the recipient site the loss of existing hair is often referred to as “shock loss.” So far there is no consensus whether the effluvium is telogen,1-5 anagen,6-11 or a combination of both.12
In the donor region the same confusion exists in regard to hair loss after follicular unit harvesting. Most hair transplant surgeons label this as telogen effluvium.13-16 Some consider this the same entity as recipient site shock loss. Marzola and Vogel were amongst the very few that described the effluvium as anagen.17
Why is it important to make the distinction? By relating the effluvium to the hair cycle one would be able to predict the course of this distressing complication. Nowadays patients are so well informed that any ambiguity from the surgeons in regard to their loss of hair after surgery will fail to convey confidence and reassurance.
Why is it important to make the distinction? By relating the effluvium to the hair cycle one would be able to predict the course of this distressing complication. Nowadays patients are so well informed that any ambiguity from the surgeons in regard to their loss of hair after surgery will fail to convey confidence and reassurance.
Objective
Our objective was to study the onset of hair loss in the donor site after hair transplantation in order to determine whether it should be classified as anagen or telogen effluvium.
Materials and Methods
We reviewed two studies that were presented at the 2008 ISHRS Annual Scientific Meeting held in Montréal, Canada.
The first study was conducted by Lorenzo in 2003 involving 400 hair transplant surgeries harvested by the FUE technique.18 The second was a prospective and retrospective study conducted by Ng and Pathomvanich in 2007-08. All cases reported to have hair loss in the donor site were studied.19 Both studies examined various aspects of donor site effluvium. Only those results related to the onset of hair loss are summarized here.Result of this study was published in Hair Transplant Forum International ( Vol 20:2, Mar / Apr 2010 )
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Results
1. Lorenzo’s study. Donor site effluvium occurred infrequently after FUE (incidence not quoted in the abstract). The average time between surgery and the appearance of hair loss was 20 days. The zones that presented effluvium were limited and not exceeding 25% of the donor surface.
2. Ng and Pathomvanich’s study. Retrospective study: The medical records of 169 patients who had surgery from July to November 2007 were examined. Six patients reported donor site effluvium. |
Prospective study
177 patients undergoing hair transplantation from January to May 2008 were informed of the study and asked to report any kind of hair loss post-operatively. A questionnaire was sent out 6-12 weeks after surgery to 97 patients who could be contacted by email. Twelve patients reported hair loss around the incision.
Combining the data from the retrospective and prospective studies: Amongst these 18 patients, 11% (2 patients) noticed hair loss as early as 1-3 weeks after surgery. The majority, 72.2% (13 patients), claimed that hair loss started at 3-5 weeks. In 16.7% (3 patients), the effluvium was delayed until 7-9 weeks. No case was reported after 9 weeks (Chart 1). The most common pattern of effluvium was hair loss all along and on both sides of the wound (Figures 1, 2, and 3). None of these patients developed hair loss in the recipient site.
Discussion
As only about 10% of the scalp hair follicles are in telogen at any time, the extent of donor effluvium in both studies suggests that the injury associated with hair transplantation is inflicted upon hair in the anagen phase.
Anagen can be subdivided into six stages, starting from the migration of bulge stem cells downward towards the dermal papilla, until the fully developed hair emerges above the skin surface. Direct insult to the rapidly dividing keratinocytes will have two possible outcomes:20
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1. Hair damage without anagen release. Matrix cell division and differentiation are abruptly and temporarily reduced, but without termination. As a result the partially keratinized portion of growing hair shaft is weakened. The weakened hair continues to grow at 1cm per month. Since anagen hair bulbs are located in the subcutaneous tissue approximately 4mm from the scalp surface, it takes about 2 weeks for the damaged section of the hair shaft to reach the scalp surface.
Once free of the supporting follicular duct, the anagen hair will break off at this narrowed point. Shedding occurs 2-6 weeks after surgery. This is the classic form of anagen effluvium. Up to 90% of scalp hair is potentially affected sparing the telogen hair. Hair will regrow after weeks to months.
When examined under the microscope, the affected hair is “dystrophic” with a tapered proximal end and lack of root sheaths. On occasion, the hair is tapered (Pohl Pinkus Lines) without fracture and does not lead to hair loss.
2. Hair damage with immediate anagen release. Matrix cell proliferation is ceased followed by termination of anagen. Spontaneously the damaged hair enters into the catagen phase, during which the dermal papilla contracts upwards and is released from the apoptotic lower follicle. The hair root is shortened and its terminal portion becomes club-shaped. Formation of this normal club hair marks the completion of catagen and the beginning of telogen.21 | .
A normal human follicle containing a club hair may simultaneously reinitiate early anagen.22 Telogen and anagen may therefore be occurring in the same follicle at the same time. The common belief that the new anagen hair mechanically displaces the old club hair appears to be unlikely. First, each telogen shaft sits in its own epithelial sac quite separate from the anagen portion. Second, multiple shafts, as noted by Kligman, can exist in the same follicle. Finally, anagen shafts may grow past an adherent telogen shaft.
It is now believed that shedding of the club hair is mediated by a distinct and active proteolytic process known as exogen.23 Though exogen also occurs in telogen follicles, the largest peak of exogen is coupled to anagen. That most club hairs do not shed during telogen is important in timing any effluvium. Take into consideration that the hair cycle progresses as follows:24
- Catagen: 2 to 4 weeks
- Telogen: 8 to 16 weeks
- Early anagen/exogen: unknown
It then would take at least 10 weeks before a club hair is shed after initial damage to an anagen follicle. The increase loss of normal club hair was first termed telogen effluvium by Kligman in 1961.25 Some prefer the term telogen “defluvium” to precisely describe excessive hair loss. Immediate anagen release was listed by Headington as the most acute form of his five functional types of telogen effluvium. 22 The other four types generally take 3-4 months, or longer, for shedding to occur.
Looking at the results of both studies, it would be reasonable to conclude that postsurgical donor site effluvium is a classic form of anagen effluvium without anagen release, rather than acute telogen effluvium, which takes a minimum of 10 weeks to occur.
Conclusion
The most important clinical feature in distinguishing anagen from telogen effluvium is the onset of hair loss after exposure to the noxious stimuli. If the preexisting hair in the donor site falls out 2-9 weeks after hair transplantation, the mechanism is most likely an anagen effluvium according to the commonly used terminology. Confirmation will require microscopic examination of the shed hair.
References
1. Leavitt, M. Corrective Hair Restoration. In D. Stough and R. Haber, eds. Hair Replacement Surgical and Medical. Mobsy 1996; 313.
2. Stough, D. The Consultation. In R. Haber and D. Stough. Hair Transplantation. Elsevier Saunders 2006, 46.
3. Bernstein, R.M., and W.R. Rassman. Telogen Effluvium. In: W.P. Unger and R. Shapiro, eds. Hair Transplantation. New York: Marcel Decker, 2004; 395-396.
4. Karamanovski, K. Hair-styling technique to camouflage post-operative thinning in women. Hair Transplant Forum Int’l. 2007; 17(2):73.
5. Shapiro, R. Why comparing techniques in hair restoration surgery is an intrinsically difficult task. Hair Transplant Forum Int’l. 2007; 17(5):157
6. True, R., and R. Dorin. A protocol to prevent shock loss. Hair Transplant Forum Int’l. 2005; 15(6):197-199.
7. Unger, W.P. Postsurgical effluvium of preexisting hair. In: W.P. Unger and R. Shapiro, eds. Hair Transplantation, 4th edition. New York: Marcel Decker, 2004; 562.
8. Cole, J. Post-transplant anagen effluvium. Hair Transplant Forum Int’l. 2002; 12(3):115.
9. Shiell, R. Notes from the Editor Emeritus. Hair Transplant Forum Int’l. 2002; 12(2):54.
10. Knudsen, R. Notes from the Editor Emeritus. Hair Transplant Forum Int’l. 2005; 15(2):45.
11. Lusicic, N., A. Susacasa, and S. Araujo. A method for removing scabs in the post-operative stage in hair restoration surgery. Hair Transplant Forum Int’l. 2004; 14(3):95.
12. Perez-Meza, D., M. Leavitt, and M. Mayer. The growth factors, part I: clinical and histological evaluation of the wound healing and revascularization of the hair graft after hair transplant surgery. Hair Transplant Forum Int’l. 2007; 17(5):173.
13. Stough D., Haber R. The Donor Area. In: D. Stough and R. Haber. Hair Replacement Surgical and Medical. Mobsy: 1996; Table 5-2, 137.
14. Beehner, M. “Focal dense-packing” in hair transplantation. Hair Transplant Forum Int’l. 2008; 18(1):1-7.
15. Pak, J., et al. Management of the occipital scalp tension wound in hair transplant surgery with the Quill suture. Hair Transplant Forum Int’l. 2008; 18(4):149.
16. Martinick, J. Cyberspace Chat. Hair Transplant Forum Int’l. 2003; 13(2):305.
17. Marzola, M., and J. Vogel. In: R. Haber and D. Stough. Hair Transplantation. Elsevier Saunders, 2006; 175.
18. Lorenzo, J. Abstract: Post-surgical telogen effluvium of the donor zone after FUE technique. Oral Presentation. ISHRS 16th Annual Meeting, Montréal, Canada; 2008.
19. Ng, B., and D. Pathomvanich. Donor site effluvium: retrospective and prospective studies to define the incidence, onset, pattern, and associated factors. Oral Presentation. ISHRS 16th Annual Meeting, Montréal, Canada; 2008.
20. Olsen, E., ed. Disorders of Hair Growth Diagnosis and treatment. 2nd Edition. McGraw-Hill, 2003; 275-302.
21. Dawber, R. Diseases of the Hair and Scalp. 3rd Edition. Blackwell Science, 1997. 7.
22. Headington, J. Telogen effluvium—new concepts and review. Arch Dermatol. 1992; 129:356-363.
23. Yoram, M. et al. Exogen, shedding phase of the hair growth cycle: characterization of a mouse model. Journal of Investigative Dermatol. 2002; 119:639-644.
24. About Hair Loss: Hair Loss and the Hair Growth Cycle. ISHRS website, www.ishrs.org.
25. Kligman, A. Pathologic dynamics of human hair loss, I: telogen effluvium. Arch Dermatol. 1961; 83:175-198.
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