Evaluation of trichoscopic features in female pattern hair loss

Female pattern hair loss (FPHL) is explained by decrease in hair fiber production and their eventual miniaturization. It is considered a counterpart of male androgenetic alopecia but the role of androgens in its pathogenesis is yet to be proven. To evaluate the trichoscopic features in females with patterned hair loss. Inclusion and exclusion criteria were applied and 37 cases were enrolled in our study. Detailed history and clinical examination were done to establish the diagnosis. Trichoscopic examination was done after taking consent in diagnosed cases. On trichoscopy, hair diameter variability, peri pilar sign, white dots, scalp pigmentation and focal atrichia was observed in 62.2%, 62.2%, 40.5%, 45.9% and 40.5% respectively. Most common trichoscopy finding observed was peri pilar sign and hair diameter variability in 23/37 females. Definitive diagnosis of FPHL is difficult to be established solely on the basis of clinical examination. Thus, trichoscopy serves as a non-invasive tool to ascertain the diagnosis in these patients.

Evaluation of Hair Density and Hair Diameter in the Adult Thai Population Using Quantitative Trichoscopic Analysis

The data of hair density and hair diameter in the Asian population, especially in Thais, are limited. We aimed to evaluate hair density and hair diameter of members of the Thai population at different scalp sites and to determine the effect of sex and aging as well as to compare the results with those in groups of other ethnicities. Healthy Thais whose hair examination findings were normal were evaluated. Two hundred and thirty-nine subjects participated in this study, of whom 79 were male and 160 were female. Hair density and hair diameter were analyzed at four different scalp sites using quantitative trichoscopic analysis. The highest hair density in Thais was observed in the vertex area. Hair densities at four different scalp sites were significantly different from one another; only hair density at the vertex site showed no significant difference from that in the occipital area. In contrast, hair diameter did not show any statistically significant differences for the different sites. We observed decreased mean hair density with increasing age and found statistically significant differences between participants in their 20s and those in their 60s, while hair diameter remained consistent. Comparing our results with a previous study in other ethnicities, the hair densities in Asians are generally lower. In conclusion, hair density in the Thai population varies at different scalp sites. Aging is a factor in declining hair density. Asians have a lower hair density compared to Caucasian and African populations.

Congenital symmetrical circumscribed patterned non-scarring alopecia of eyebrows: a variant of congenital triangular alopecia or an anatomical variation?

Triangular alopecia presents as a unilateral triangular-shaped non-scarring alopecia usually involving the temporal scalp. There are few reports of occipital scalp involvement and bilateral disease. Usually it is seen at 2–3 years of age but occasionally can be present at birth. Here we present a unique case of triangular alopecia involving the eyebrows in a 23-year-old man. He had bilateral symmetrical involvement since birth. Points in favour of triangular alopecia in our case were non-scarring alopecia, oval-to-triangular shape, fringe of terminal hair at superior margin; trichoscopy showing significant decrease in hair diameter diversity with increased number of vellus and intermediate hair and histopathology showing normal hair follicle density and increased vellus and intermediate hair (miniaturisation) with absence of inflammation on histopathology. Other differential diagnoses kept were partial duplication of eyebrows, congenital alopecia areata and mild form of ectodermal dysplasia.

HAIR DIAMETER COMPARISON BETWEEN SLICK- AND WILD TYPE-HAIRED PUERTO RICAN HOLSTEIN COWS

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