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Updated: Feb 14, 2026
Dual-mode Imaging of Cutaneous Tissue Oxygenation and Vascular Function
Published on: December 8, 2010
Analysis of cutaneous pigmentation in a sample
Juan Pablo Castanedo-Cazares1, Diana Hernández-Blanco1, Juan Diego García-Cortés2
1Departamento de Dermatología, Hospital Central Dr. Ignacio Morones Prieto. S.L.P., México.
Background:
The blend of hemoglobin, carotenes, and melanin defines the skin color. Constitutive pigmentation is genetically determined, facultative color is induced when skin is exposed to environment. The objective was to quantify both pigmentations in a sample of Mexican population and to analyze its relationship with sex, age, and phototype.
Methods:
We evaluated 259 individuals during the winter. Skin colorimetry was obtained by diffuse reflectance spectrometry, using the International Commission of Illumination coordenates. L*a*b* parameters were measured and the individual typological angle (ITA) was estimated from forehead, thorax, neck, forearms, and buttocks areas.
Results:
Facultative pigmentation differed from constitutive in L*, a*, and ITA° values. In men, L* and ITA° parameters were lower. Constitutive pigmentation was similar between sexes. Phototypes III, IV, and V showed differences in L*, b*, and ITA°. Facultative values such as L*, a*, ATI°, and the constitutive a* reduce as age increases.
Conclusions:
The cutaneous tones of a sample of population were quantified recognizing their values for white, light brown, and dark brown skin. A reference frame for research related to cutaneous pigmentation in Mexico is presented.
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