A study of a method for distribution analysis of skin color.
OBJECTIVE
The objective and quantitative assessment of the skin is important in medical and cosmeceutical research. Assessment of color is an important element for analyzing the surface of the skin, which is usually determined subjectively by a doctor or using color analysis devices. These devices, however, cannot provide correct color information because color is construed from the mean value of the observation region, and analysis of color distribution is impossible. The purpose of this paper is to develop an objective analysis method to permit skin color measurement of each pixel unit of an image and analyze the distribution of skin surface color.


METHODS
The Skin Color Distribution Analyzer (SCDA) is an analysis method newly developed at the Research Institute for Skin Image at Korea University. The SCDA system presented in this paper performed a novel form of quantitative and objective analysis of skin color distribution using each pixel color model parameter found in image wavelength information. In this paper, distribution analysis was conducted on normal skin and skin lesions and skin affected by artificially induced irritant contact dermatitis and pigmented nevous. The method selected a grade using a color model parameter. Twenty healthy Korean males participated in this study. A comparative study of the eight anatomical areas was performed, including the exposure and non-exposure parts and the medial aspect and the lateral aspect of the forearm. A reliability test for the SCDA system was also conducted with a spectrometer (SPEC) using the color analysis method.


RESULTS
Each skin lesion was precisely segmented by grade and each parameter had a different statistical significance for results of analysis of distribution in pigmented nevous and the artificially induced irritant contact dermatitis. Parameters L(*), b(*), a(*), and EI showed salient traits. Showed resemble measured result in the SCDA system and the SPEC of normal skin. The exposed site, in comparison with the non-exposed site, showed a notable difference in the L(*) parameter and a significant statistical difference in the x and z parameters, except b(*). The comparison of the medial and lateral aspects of the forearm showed a notable difference in the L(*) parameter and a significant statistical difference in the parameters except y and b(*). In the reliability test result using the SCDA system and the SPEC, the SCDA system was highly reliable in terms of the CV value in all color model parameters.


CONCLUSIONS
The color distribution analysis method using the SCDA system has revealed an aspect that the existent method of medical research has not shown, and is considered to be more reliable than other methods. This method can provide better study findings because it can be applied to other fields in addition to the medical science field and the ripple effect is thought to be bigger in other science field too.
Ha
Seunghan
S
Research Institute for Skin Image, College of Medicine, Korea University, Seoul, Korea.
Lee
Minhee
M
Lee
Onseok
O
Lee
Gunwoo
G
Kim
Jeayoung
J
Moon
Jongsub
J
Kim
Mingi
M
Oh
Chilhwan
C
D000328:Adult; D003124:Colorimetry / Q000295:instrumentation* / Q000379:methods*; D046169:Dermoscopy / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012867:Skin / Q000166:cytology*; D012879:Skin Physiological Phenomena