Mapping the dermoscopic features of the normal face: Findings from 200 subjects with skin of colour.

Abstract

Background Dermoscopy can potentially obviate the need for skin biopsy, particularly at cosmetically sensitive sites such as the face. While dermoscopic features of various skin diseases are well described, information on dermoscopic findings in normal skin is limited. Objectives To study the dermoscopic features of the normal face. Methods Two-hundred subjects without any facial skin disease were included in the study. Dermoscopic findings of different facial sites (forehead, bilateral zygomatic areas, bilateral cheeks, nose and chin) were evaluated using a hand-held dermoscope (Heine Delta 30) by two investigators. Dermoscopic differences between different facial sites, gender and age groups were compared. Results Most (n=156, 78%) subjects had Fitzpatrick skin type IV-VI. A background pseudonetwork was present in a majority at all the sites, except the nose (62-85% vs 41%, p<0.001). An accentuated patchy pseudonetwork was seen most commonly on the cheeks and zygoma (18-21%, p<0.001). Follicles were of uniform size and present at uniform distances in a majority at all sites, but were more commonly variable on the nose (53-70%, p<0.001). Follicular brown pigmentation was seen in 27-37% at all sites, except the forehead (9%, p<0.001). Brown circles around adnexal openings were seen most commonly on the nose (41%, p< .001). A 'dot in circle' morphology was seen most commonly on the zygoma and cheeks (25-30%, p<0.001). Vessels were more commonly seen on the cheeks (48%) and chin (27%) as compared to other sites (p<0.001). The most common vessel pattern was a linear, non-branching one. Focussed or dotted vessels were not seen at any site. White reticular lines were seen almost exclusively on the nose (15%, p<0.001). Accentuated patchy pseudonetwork, follicular plugs and brown circles around adnexal openings were more common in males, while follicular brown pigmentation was statistically significantly more common in females. Accentuated patchy pseudonetwork, follicular plugs, follicular brown pigmentation, brown circles around adnexal openings, vessels, and reticular white lines became more common with advancing age. Limitations Relatively small sample size, smaller proportion of elderly subjects, and a majority of the subjects belonging to darker skin phototypes (V-VI) Conclusion Knowledge of variations in normal dermoscopic findings of the face will help dermatologists in distinguishing abnormal from normal, and improve the interpretation of dermoscopic findings of facial skin lesions.