Joint research from Kao Corp. and the Computational Optics Group at the University of Tsukuba aims to uncover deep insights on wrinkle formation utilizing a non-invasive imaging technique known as Jones matrix-optical coherence tomography (JM-OCT).
According to the authors, with further improvement, this method could help to elucidate the relationship between wrinkles and deep structural changes in the various layers of skin. Initial results were published in Skin Research & Technology.
As Kao explained, previous researchers have indicated that the process of wrinkle formation is influenced by structural changes in the tissue density and collagen fibers of each of the skin layers. This is due to various factors such as aging and chronic exposure to ultraviolet light. However, the extent to which these structural changes in each tissue layer affects wrinkle formation had not previously been determined.
Here, a method was developed based on OCT to noninvasively observe changes in the layers of skin. By irradiating light onto the skin and analyzing its backscattering, cross-sectional images from the stratum corneum to the subcutaneous tissue can be obtained.
However, conventional OCT does not quantitatively evaluate the optical properties of the specific depths of skin layers with sufficient accuracy. Thus, JM-OCT was developed to overcome this shortcoming utilizing algorithms to acquire local data in the skin by dividing it into small sections by depth. This allowed researchers to obtain quantitative local data on the optical properties of skin at various depths in a single scan sequence, regardless of light penetration distance.
In a study of 21 female volunteers in their 70s, this technique was used to measure and calculated the average depth of wrinkles detected within a 10-mm square of the corners of their eyes. The results suggested that birefringence, degree of polarization uniformity and attenuation coefficient measurements could respectively indicate collagen‐related structures in the papillary, upper‐reticular dermis, and microstructure or tissue density in reticular dermis, that may be involved in wrinkle formation.
In the future, the company plans to use the JM-OCT approach to measure the wrinkles of people at various ages to clarify how structures in skin contribute to wrinkling. In relation, individualized measurements of an individual's susceptibility to wrinkling could lead to personalized treatments.