Spectral and photochemical parameters which define the higher efficacy of laser phototherapy in hyperbilirubinemia in newborns

摘要

Abstract: It is shown that the efficacy of phototherapy of neonatal hyperbilirubinemia is considerably increased with substitution of traditional lamp sources by the argon laser light. The spectral range of the laser (476.5 - 514.5 nm) corresponds to low-frequency slope of bilirubin absorption spectrum. This rises quantum yield of lumirubin formation which is known for its high rate of excretion. The fact can be explained by the form of absorption spectrum of bilirubin which is the sum of two spectra of weakly bound chromophores, the spectrum of chromophore responsible for lumirubin production being shifted to lower frequencies. The second cause of higher efficacy of laser phototherapy with wavelength span 476.5 ... 514.5 is the less shielding effect of hemoglobin. !2