In Vivo Determination of Skin Absorption Coefficient in a Mexican Cohort

We determined the in vivo absorption coefficient (μa) for 82 test subjects, all classified as Fitzpatrick skin phototypes II, III, IV, and V. Measurements were conducted using the integrating-sphere technique on the dorsal and palmar surfaces of the hand and the forearm. The reflectance data obtained were processed using the Inverse Adding Doubling algorithm to calculate the absorption coefficient. The mean values for this parameter ranged from 0.0132 mm−1 to 0.1021 mm−1 at a central wavelength of 624 nm. It was found that these parameters may be grouped into a distinct cohort, paving the way for studies and the design of light-based diagnostics and treatments better suited to the population in Mexico and Latin America.