Evaluation of Phototherapy Devices

1. The authors fail to distinguish adequately between photodegradation, in which bilirubin is degraded to substances of lower molecular weight, and photoisomerization, in which the pigment’s structure changes but no degradation occurs. Both processes contribute to the effects of phototherapy in humans, but their relative contributions are presently unknown. However, in the Gun rat animal model photoisomerization is more important than photodegradation and the same is likely to hold for humans. In the article the authors focus largely on photodegradation, the pathway of least importance.