Extension-induced changes in the microrelief of the human volar forearm: variations with age.
The skin microrelief can be assessed in vivo using a noninvasive method based on the image analysis of negative replicas, shadowed by oblique illumination. This technique was used to study changes in the surface furrows of the human volar forearm, related to the degree of extension, in volunteers of three age groups. Results confirmed that the skin in elderly subjects can be characterized by the lack of one of the two perpendicular furrow orientations observed in the young. During extension of the arm, the response of the microrelief in young subjects was clearly different from that in the elderly. Young skin buffered strain through a progressive shift in line density and furrow depth from one orientation to the other, whereas in the elderly, a progressive rotation of the single furrow orientation occurred. These differences would appear to be related to changes in the architecture and physical properties of the dermis. Microrelief, in the elderly subjects, showed a mean line density of 24/cm, regardless of the degree of extension. This constancy may reflect the ultimate stage in the chronological aging of the skin and may be characteristic of a loosened and relaxed dermis.
Laboratoires de Recherche Avancée de L'Oréal, Aulnay-sous-Bois, France.
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Corcuff
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de Lacharrière
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JL
Lévêque
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology*; D005260:Female; D005542:Forearm / Q000033:anatomy & histology* / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D016628:Replica Techniques / Q000295:instrumentation; D012867:Skin / Q000033:anatomy & histology*; D012879:Skin Physiological Phenomena