title: A new method to evaluate lower eyelid sag using three-dimensional image analysis.
abstract: Lower eyelid sags as well as wrinkles represent age-related morphological changes of the skin surface. However, a quantitative method to evaluate lower eyelid sagging has not been previously established. We designed a new quantitative evaluation method that uses non-invasive skin scanning, which is based on the difference between the superficial dimension of the sagging surface of the lower eyelid and the dimension of its projection area. In 97 females, 2-D and the 3-D images were taken. By 3-D image analysis, the difference between the superficial dimension of the sagging surface of the lower eyelid and the dimension of its virtual projection area was assessed, and was defined as the sag parameter. This parameter was significantly correlated with the sag score (a photographic scale to assess the degree of sagging) and with aging. The accuracy of the sag parameter was confirmed in a clinical test using a sag treatment lotion and a placebo lotion. The sag score decreased in skin treated with the sag treatment lotion, but the change was not significantly different from that of the placebo treated skin. On the contrary, the sag parameter was significantly reduced (P < 0.05) after topical application of the sag treatment lotion compared with the placebo-treated skin. These results indicate that the sag parameter as proposed herein is useful in clinical studies to evaluate slight changes in lower eyelid sagging.
authors.affiliation: Biological Science Laboratories, Kao Corporation, Tochigi, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Fukuda
authors.forename: T
authors.initials: T
authors.lastname: Fujimura
authors.forename: S
authors.initials: S
authors.lastname: Moriwaki
authors.forename: T
authors.initials: T
authors.lastname: Kitahara