Fig. 11: Overlay of wide-range HSI Z-profiles from a healthy subject and a severely jaundiced patient.

a Comparison of mixed-type skin HSI responses between Patient ID 018 (cyan-bluish polyline, Jaundice Index = 0.25) and Patient ID 032 (yellow-orange polyline, Jaundice Index = 21.11). Severe jaundice is characterized by elevated yellow–orange wavelength responses, highlighted in the red-orange box, with a core increase typically observed in the 560–590 nm range, and reduced reflectance for wavelengths λ < 550 nm, as indicated by the purple dashed box. b Comparison of palm-crease HSI responses between Patient ID 018 (0.25) and Patient ID 032 (21.11). Severe jaundice exhibits an overall lower spectral response, except for two pronounced peaks near 800 nm and 850 nm.