International Journal of Trichology

: 2022  |  Volume : 14  |  Issue : 5  |  Page : 153--155

Sense and nonsense of trichoscopy

Ralph Michel Trüeb 
 Center for Dermatology and Hair Diseases Professor Trüeb, Zurich-Wallisellen, Switzerland

Correspondence Address:
Ralph Michel Trüeb
Center for Dermatology and Hair Diseases Professor Trüeb, Bahnhofplatz 1A, CH-8304 Zurich-Wallisellen

How to cite this article:
Trüeb RM. Sense and nonsense of trichoscopy.Int J Trichol 2022;14:153-155

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Trüeb RM. Sense and nonsense of trichoscopy. Int J Trichol [serial online] 2022 [cited 2023 Feb 8 ];14:153-155
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Full Text

“I could not agree more with the statement of Antonella Tosti that diagnosing hair and scalp disorders without trichoscopy is a professional practice gap.”

–Lidia Rudnicka

Dermoscopy refers to the dermatoscope, a magnifier (typically ×10) with a light and a liquid medium between the instrument and the skin used for the examination of the skin. Also known epiluminescence microscopy, it allows for inspection of skin lesions unobstructed by skin surface reflections. When the images are digitally processed, the technology is also referred to as a digital epiluminescence dermoscopy.

The technique has originally been introduced in dermatology for distinguishing benign from malignant skin lesions, particularly in the diagnosis of pigmented skin lesions. In 1989, German dermatologists developed a new device for dermoscopy in collaboration with the medical device manufacturer HEINE Optotechnik, which was handheld and illuminated by a halogen lamp featuring an achromatic lens with 10-fold magnification. To reduce light reflection, the lesion was covered with immersion oil. This technique helped to diagnose pigmented skin lesions more precisely, as confirmed by Stolz from the Ludwig Maximilian University of Munich.[1] At the Medical University of Vienna, a dermatoscope based on cross-polarization was developed and patented, a technique further used in digital dermatoscopy such as the MoleMax™ device and the FotoFinder™. Subsequently, a California medical device manufacturer, 3 Gen, introduced the first polarized handheld dermatoscope, the DermLite™. Polarized illumination, coupled with a cross-polarized viewer, reduces (polarized) skin surface reflection, thus, allowing visualization of the skin structures without immersion fluid. With the marketing of polarized dermatoscopes, dermoscopy increased in popularity among dermatologists expanding the technique for the study of further skin pathologies. Due to the fairly standardized imaging and limited amount of diagnoses compared to clinical dermatology, dermoscopic images eventually became a center of interest for automated medical image analysis and its commercial utilization in clinical practice.

In fact, skin surface microscopy started as early as 1663 by Kolhaus for capillary microscopic examination of the nail bed,[2] and was improved with the addition of immersion oil in 1878 by Ernst Abbe[3] Finally, German dermatologist, Saphier, added a built-in light source to the instrument, provided the first detailed description of possible applications in dermatology, and was the first to coin the term dermatoscopy in 1920.[4]

Eventually, dermoscopy was introduced for the hair and scalp evaluation by Antonella Tosti with a respective textbook on “Dermoscopy of Hair and Scalp,”[5] and originally named trichoscopy by Rudnicka et al.[6] This simple method allows viewing of the hair and scalp at high magnifications (10 fold to 70 fold) and can be combined with photography and digital imaging. Using dermoscopy, signature patterns are seen in a range of scalp and hair conditions that have provided the foundation for diagnostic algorithms.[7] And yet, algorithms may be useful for the initiate and the average diagnosis, but they fail when signs are vague, multiple, or confusing.[8] Although the dermatoscope is a practical instrument for use in routine practice, clinicians need to know that the sensitivity may be affected by multiple factors and overlapping features. All of these can be overcome in everyday practice with growing familiarity with dermoscopy through regular and frequent use of the device (”learning by doing”), but most importantly, an understanding that dermoscopy represents an integral part of a comprehensive dermatological examination. Finally, costly, multi-parameter computer-assisted technologies are the least effective in clinical practice.[9]

In fact, epiluminiscence microscopy of the hair and scalp has been performed by trichologists, a nonmedically qualified discipline founded as early as 1902, long before its introduction into dermatology, although without the sophistication of the clinical pathologic correlations conferred to dermatologists through their academic learning. Over the following decades, the branch started gaining momentum, and in 1974, the first trichology course was developed at the University of Southern California.[10]

Despite the current plethora of seminars, online courses, and apps on trichoscopy, it would be imprudent to replace well-tried dermatologic examination procedures with dermoscopy, such as the trichogram in telogen effluvium, light microscopic analysis in disorders of the hair shaft, microbiological studies in infectious diseases of the scalp, scalp biopsy for histopathological examination, and direct immunofluorescence studies in the scarring alopecias. So far, only in the diagnosis of early female androgenetic alopecia, dermoscopy has proven to be superior to the respective traditional diagnostic procedure.[11] In addition, dynamic trichoscopy encompasses the use of dermoscopy for invasive diagnostic (biopsy) or therapeutic procedures (intralesional therapy or surgical) in hair and scalp disease, for monitoring of therapy, and for the appreciation of disease-specific evolution over time.[12]

In fact, based on the dermoscopic features of trichotillomania, there has been a recent report of children with the habit of hair pulling erroneously diagnosed as trichotillomania[13] while the propositus did not fulfill the Diagnostic and Statistical Manual of Mental Disorders-5 criteria for trichotillomania.[14] Therefore, as a diagnostic procedure, trichoscopy is also to be understood as representing an integral part of a more comprehensive medical education. Ultimately, the dermatologist participates with the other medical disciplines in the diagnosis and treatment of all types of hair problems as they may relate to systemic disease.[15]

We have formerly acknowledged that in dermatology, the dermatoscope may pick up from the culture of the stethoscope in internal medicine in terms of being a time-tested, sophisticated, and handheld diagnostic medical instrument conferring dignity in the hands of dermatologists.[16] And yet, despite the enthusiasm emerging with its establishment as a dermatologic tool in the diagnosis of hair and scalp disorders, caution is warranted not to elevate trichoscopy to something like a fetish status.[17] As a diagnostic procedure, trichoscopy is also to be understood as representing an integral part of the surface or epiluminescence microscopy of the skin (dermoscopy), and as such the query arises, what the purpose has been of coining a discrete term for dermoscopy of the hair and scalp? By analogy, stethoscopy of the heart and of the lung does not have separate labels either.

In fact, the term trichoscopy would even seem etymologically inaccurate since it refers to the hair, from Greek θρίξ, while actually an important fraction of the trichoscopic signature patterns involve peculiarities of the scalp skin as they relate to disease.

Statements on the value of trichoscopy are summarized in [Table 1].{Table 1}


1Stolz W. Skin surface microscopy. Lancet 1989;334:864-5.
2Gilje O, O'Leary PA, Baldes EY. Capillary microscopic examination in skin disease. Arch Dermatol 1958;68:136-54.
3Diepgen P. History of Medicine. Berlin: de Gruyter; 1965. p. 138-53.
4Saphier J. Dermatoscopy. I. Communication. Arch Dermatol Syphiol 1920;128:1-19.
5Tosti A. Dermoscopy of Hair and Scalp: Pathological and Clinical Correlation. Illustrated Editor. USA: CRC Press; 2007. p. 51-3.
6Rudnicka L, Olszewska M, Majsterek M, Czuwara J, Slowinska M. Presence and future of dermoscopy. Expert Rev Dermatol 2006;1:769.
7Inui S. Trichoscopy for common hair loss diseases: Algorithmic method for diagnosis. J Dermatol 2011;38:71-5.
8Groopman J. How Doctors Think. Boston, New York: Houghton Mifflin Company; 2007.
9Lown B. Lost Art Of Healing. Practicing Compassion in Medicine. New York: Random House; 1999.
10Trüeb RM, Vañó-Galván S, Kopera D, Jolliffe VML, Ioannides D, Gavazzoni Dias MF, et al. Trichologist, dermatotrichologist, or trichiatrist? A global perspective on a strictly medical discipline. Skin Appendage Disord 2018;4:202-7.
11Galliker NA, Trüeb RM. Value of trichoscopy versus trichogram for diagnosis of female androgenetic alopecia. Int J Trichology 2012;4:19-22.
12Trüeb RM, Rezende HD, Diaz MF. Dynamic trichoscopy. JAMA Dermatol 2018;154:877-8.
13Fernandes MR, Melo DF, Vincenzi C, Lima CD, Tosti A. Trichotillomania incognito: Two case reports and literature review. Skin Appendage Disord 2021;7:131-4.
14Trüeb RM. Trichotillomania or Tic d'Épilation? Skin Appendage Disord 2021;7:431-2.
15Jakovljević M, Ostojić L. Comorbidity and multimorbidity in medicine today: Challenges and opportunities for bringing separated branches of medicine closer to each other. Psychiatr Danub 2013;25 Suppl 1:18-28.
16Trüeb RM, Dias MF. A comment on trichoscopy. Int J Trichology 2018;10:147-9.
17Broom A, Kirby E, Gibson AF, Post JJ, Broom J. Myth, manners, and medical ritual: Defensive medicine and the fetish of antibiotics. Qual Health Res 2017;27:1994-2005.