Data

Reference values

The most important measurements that can be made with TrichoScan® are hair density and hair thickness. The best way to measure the total hair mass is by calculating the cumulative hair thickness which represents the sum of all hair diameters in the test field.

Any measurement reflects the status quo at the time of measurement and the measured hair parameters are largely dependent on where the analysis has been performed (crown, vertex, temporal recessions), the degree of hair loss (bald or just hair thinning), the treatment (before or after treatment), and the natural hair color (blond hair is usually thinner than dark hair) just to mention a few variables. As a consequence, there are no suitable standard reference values for hair.

However, with the TrichoScan® individual hair parameters can be monitored, provided the same area is analysed later in time. For this purpose, the hair density at a hair loss area on the top of the head is compared with the normal hair density at the back of the head. In this procedure, the hair density at the back of the head is the individual normal value, i.e. the hair density that was present before the onset of hereditary hair loss on the top of the head. If the hair density at the back of the head is, for example, 250 hairs/cm² and at the top of the head 150/cm², the person has already lost 100/cm² of hair. As a rule, the normal hair density of the Central European population is around 230 - 280 hairs per cm².

Publications on TrichoScan®

Technical journal articles

R. Hoffmann, H. Lüdtke.
Trichoscan®.
In: FM Camacho, A Tosti(eds); Montagna Trichology Diseases of the pilosebaceus follicle Vol I (2016), Page 177-183 Download

R. Hoffmann, H. Lüdtke, M. Hoffman-Wecker, B. J. Hughes-Formella.
Digital imaging for measuring of hair growth on the human scalp.
In: E. Berardesca et al. (eds); Non Invasive Diagnostic Techniques in Clinical Dermatology (2014), Page 413-422

Research articles

Blume-Peytavi U, Issiakhem Z, Gautier S, Kottner J, Wigger-Alberti W, Fischer T, Hoffmann R, Tonner F, Bouroubi A, Voisard JJ
Efficacy and safety of a new 5% minoxidil formulation in male androgenetic alopecia: A randomized, placebo-controlled, double-blind, noninferiority study.
J Cosmet Dermatol. 2018 Apr 16. doi: 10.1111/jocd.12541. Link

J Gassmueller, E Rowold, T Frase and B Hughes-Formella
Validation of TrichoScan ® technology as a fully-automated tool for evaluation of hair growth parameters.
Eur J Dermatol (2009) Feb (12): 224-31  Download

J Gassmueller, R Hoffmann and A Webster
Topical fulvestrant solution has no effect on male and postmenopausal female androgenetic alopecia: results from two randomized, proof-of-concept studies.
British Journal of Dermatology (2008) 158, 109–115

R Hoffmann
A 4-month, open-label study evaluating the efficacy of eflornithine 11.5% cream in the treatment of unwanted facial hair in women using TrichoScan.
Eur J Dermatol (2008) 18 (1): 65-70  Download

R Hoffmann  (comment to Van Neste)
TrichoScan, a GCP-validated tool to measure hair growth.
JEADV (2008) 22, 101–136

N Lengg, Heidecker B, Seifert B, RM Trüeb
Dietary supplement increases anagen hair rate in women with telogen effluvium: results of a double-blind, placebo-controlled trial.
Therapy (2007) 4, 59–65

D Van Neste, RM Trüeb
Critical study of hair growth analysis with computer-assisted methods.
JEADV (2006) 20, 578–583
 

U Blume-Peytavi, C Kunte, A Krisp, N Garcia Bartels, U Ellwanger, R Hoffmann
Comparison of the efficacy and safety of topical minoxidil and topical alfatradiol in the treatment of androgenetic alopecia in women.
JDDG (2007) 5 (5): 391-395 Download

R Hoffmann and D Van Neste
Recent Findings with Computerized Methods for Scalp Hair Growth Measurements.
J Investig Dermatol Symp Proc 2005 Dec;10(3):285-8.

R Hoffmann
TrichoScan: What Is New?
Dermatology (2005) 211:54–62

A J Chamberlain and R Dawber
Methods of evaluating hair growth.
Australasian Journal of Dermatology (2003) 44:10–18

R Hoffmann
TrichoScan: A Novel Tool For The Analysis of Hair Growth in vivo.
J Investig Dermatol Symp Proc. 2003 Jun;8(1):109-15.

R Hoffmann
TrichoScan: Ein neues Werkzeug für die digitale Haarzählung.
Hautarzt (2002) 53:798–804 Download

R Hoffmann
TrichoScan: combining epiluminescence microscopy with digital image analysis for the measurement of hair growth in vivo.
Eur J Dermatol (2001) 11: 362-368 Download

Publications on hair growth and hair loss measurement 

  • de Lacharriere-O; Deloche-C; Misciali-C; Piraccini-BM; Vincenzi-C; Bastien-P; Tardy-I; Bernard-BA; Tosti-A: Hair diameter diversity: a clinical sign reflecting the follicle miniaturization. Arch Dermatol. MAY 2001; 137 (5):641-646
  • Van-Neste-D; Fuh-V; Sanchez-Pedreno-P; Lopez-Bran-E; Wolff-H; Whiting-D; Roberts-J; Kopera-D; Stene-JJ; Calvieri-S; Tosti-A; Prens-E; Guarrera-M; Kanojia-P; He-W; Kaufman-KD: Finasteride increases anagen hair in men with androgenetic alopecia. BRITISH-JOURNAL-OF-DERMATOLOGY. OCT 2000; 143 (4) : 804-810
  • Gehring-W; Gloor-M: Das Phototrichogramm als Verfahren zur Beurteilung haarwachstumsfördernder Präparate am Beispiel einer Kombination von Hirsefruchtextrakt, L-Cystin und Calciumpantothenat. H+G (2000) 75:397-496
  • Whiting-DA; Waldstreicher-J; Sanchez-M; Kaufman-KD: Measuring reversal of hair miniaturization in androgenetic alopecia by follicular counts in horizontal sections of serial scalp biopsies: Results of finasteride 1 mg treatment of men and postmenopausal women. JOURNAL-OF-INVESTIGATIVE-DERMATOLOGY-SYMPOSIUM-PROCEEDINGS. DEC 1999; 4 (3) : 282-284
  • Price-VH; Menefee-E; Strauss-PC: Changes in hair weight and hair count in men with androgenetic alopecia, after application of 5% and 2% topical minoxidil, placebo, or no treatment. JOURNAL-OF-THE-AMERICAN-ACADEMY-OF-DERMATOLOGY. NOV 1999; 41 (5) Part 1 : 717-721
  • Price-VH; Menefee-E; Strauss-PC: Changes in hair weight and hair count in men with androgenetic alopecia, after application of 5% and 2% topical minoxidil, placebo, or no treatment. J-Am-Acad-Dermatol. 1999 Nov; 41
  • Van-Neste-D: Human scalp hair growth and loss evaluation methods: is there simple and reliable method? Exp-Dermatol. 1999 Aug; 8(4): 299-301
  • Gruber-DM; Berger-UE; Sator-MO; Horak-F; Huber-JC: Computerized assessment of facial hair growth. FERTILITY-AND-STERILITY. OCT 1999; 72 (4) : 737-739
  • Hutchinson-PE; Thompson-JR: The size and form of the medulla of human scalp hair is regulated by the hair cycle and cross-sectional size of the hair shaft. BRITISH-JOURNAL-OF-DERMATOLOGY. MAR 1999; 140 (3) : 438-445
  • Guarrera-M; Semino-MT; Rebora-A: Quantitating hair loss in women: A critical approach. DERMATOLOGY-. 1997; 194 (1) : 12-16
  • Hutchinson-PE; Thompson-JR: The cross-sectional size and shape of human terminal scalp hair. BRITISH-JOURNAL-OF-DERMATOLOGY. FEB 1997; 136 (2) : 159-165
  • Hayashi-S; Miyamoto-I; Takeda-K: Measurement of human hair growth.BIOENGINEERING-OF-THE-SKIN-SKIN-SURFACE-IMAGING-AND-ANALYSIS. 1997; : 241-250
  • Van-Neste-DJ; Rushton-DH: Hair problems in women. Clin-Dermatol. 1997 Jan-Feb; 15(1): 113-25
  • Van Neste DJJ, De Brouwer B, De Coster W: The Phototrichogram: Analysis of Some Technical Factors of Variation. Skin Pharmacol 1994; 7:67-72
  • Van Neste DJJ: Hair Growth Evaluation in Clinical Dermatology (Editorial) Dermatology (1993) 187:233-234
  • Alcaraz-MV; Villena-A; Perez-de-Vargas-I: Quantitative study of the human hair follicle in normal scalp and androgenetic alopecia. J-Cutan-Pathol. 1993 Aug; 20(4): 344-9
  • Peereboom-Wynia-JD; Beek-CH; Mulder-PG; Stolz-E: The trichogram as a prognostic tool in alopecia areata. Acta-Derm-Venereol. 1993 Aug; 73(4): 280-2
  • Rushton-DH; de-Brouwer-B; de-Coster-W; van-Neste-DJ: Comparative evaluation of scalp hair by phototrichogram and unit area trichogram analysis within the same subjects. Acta-Derm-Venereol. 1993 Apr; 73(2): 150-3
  • Hayashi-S; Miyamoto-I; Takeda-K: Measurement of human hair growth by optical microscopy and image analysis. Cosmetics Laboratory, Kanebo Ltd, Odawara, Japan. Br-J-Dermatol. 1991 Aug; 125(2): 123-9
  • Rushton-DH; Ramsay-ID; Norris-MJ; Gilkes-JJ. Natural progression of male pattern baldness in young men. Clin-Exp-Dermatol. 1991 May; 16(3): 188-92
  • Price-VH; Menefee-E: Quantitative estimation of hair growth. I. androgenetic alopecia in women: effect of minoxidil. J-Invest-Dermatol. 1990 Dec; 95(6): 683-7
  • Rushton-DH; Ramsay-ID; James-KC; Norris-MJ; Gilkes-JJ: Biochemical and trichological characterization of diffuse alopecia in women. Br-J-Dermatol. 1990 Aug; 123(2): 187-97
  • Peereboom-Wynia-JD; van-der-Willigen-AH; van-Joost-T; Stolz-E: The effect of cyproterone acetate on hair roots and hair shaft diameter in androgenetic alopecia in females. Acta-Derm-Venereol. 1989; 69(5): 395-8
  • Rushton-DH; Unger-WP; Cotterill-PC; Kingsley-P; James-KC: Quantitative assessment of 2% topical minoxidil in the treatment of male pattern baldness. Clin-Exp-Dermatol. 1989 Jan; 14(1): 40-6
  • Pelfini-c, Calligaro-A: Some Notes on the Evalutaion of Hair Growth by Means of Morphometric Computerized Analysis. J Appl. Cosmetol. 1986; 4: 67-76
  • Gibbons-RD; Fiedler-Weiss-VC: Computer-aided quantification of scalp hair. Dermatol-Clin. 1986 Oct; 4(4): 627-40
  • Guarrera M, Ciulla MP: A Qunatitative Evaluation of Hair Loss: The Phototrichogram. J Appl. Cosmetol. 1986; 4: 66-66
  • Mortimer-CH; Rushton-H; James-KC: Effective medical treatment of common baldness in women. Clin-Exp-Dermatol. 1984 Jul; 9(4): 342-50
  • Rushton-H; James-KC; Mortimer-CH: The unit area trichogram in the assessment of androgen-dependent alopecia. Br-J-Dermatol. 1983 Oct; 109(4): 429-37
  • Jackson-D, Church-RE, Ebling-FJ: Hair Diameter in Female Baldness. Br. J. Derm. (1972) 87:361-367
  • Barman-JM; Astore-I; Pecoraro-V: The Normal Trichogram of the Adult. Journal of Investigative Dermatology, 44:233-236