Frontier in hair loss and trichoscopy: A review

Abstract

<p>Skin surfaces have always been examined using dermoscopy, a familiar tool which is useful to magnify and examine skin especially in cases of pigmented skin lesions. However, to examine the hair and scalp, a practical tool called trichoscopy has surfaced recently and has proven to be handy and functional in diagnosing most hair-related diseases. It is also referred to as dermoscopy of the hair and the scalp. It can aid in assessing active diseases in the scalp and hair, such as yellow dots, dystrophic hairs, cadaverized black dots, white dots, and exclamation mark hairs – all of which denote specific criteria for hair diseases. Trichoscopy is a very newly developed non-invasive technique for hair image analysis. It permits non-invasive visualization of hair shafts at higher intensification (about ×70 and ×100) and enables measurement of hair shaft width without the need for removing hair for diagnostic reasons. Moreover, it helps <em>in vivo</em> visualization of the epidermal portion of hair follicles and perifollicular epidermis (orifices). Consequently, it is valuable as it permits the inspection of structures that are otherwise not seen by the naked eye. Trichoscopy is the new frontier for the diagnosis of hair and scalp disease. Nowadays, a trichoscope is considered a must for dermatologists and it is a hot topic in the treatment of hair diseases. There is pooled evidence that the utilization of trichoscopy in the clinical setting for evaluating hair disorders can improve its diagnostic capability beyond simple clinical scrutiny. Trichoscopy can identify both hair shaft and hair opening abnormalities without the need for hair sampling, as well as distinguish between different scalp and hair diseases. Furthermore, it can give easy and quick evaluation of the hair with a follow-up to determine progress and prognosis of the disease with photos. It can also aid in some genetic hair shaft dystrophies such as trichorrhexis nodosa, trichorrhexis invaginata, monilethrix, pili annulati, and pili torti. The limitation of trichoscopy is that it needs prior knowledge to apply it effectively in order to mandate an efficient use by correctly interpreting the findings and their significance. In cases where there are unsettled discrepancies, a histopathological investigation is needed. The interest in trichoscopy has vastly increased and has become an indispensable tool in evaluating patients with hair loss. The aim of this review is to supplement existing knowledge on trichoscopy with recent readings of different scalp and hair conditions that are commonly encountered in clinical settings.</p>