Method for Designing and Characterizing Phototherapy Shields

Abstract

Optimal shield properties and design are of vital importance for preventing adverse effects of light-based clinical procedures. The goal of this study was to select the most appropriate materials for a two-layer phototherapy shield. Four biocompatible fabrics, to be utilized as the layer contacting patients’ skin, and two reflective materials, to be utilized as the layer facing the light source, were investigated. The optical properties of the four biocompatible fabrics and transmittance of the two reflective materials were determined in the 400–500 nm range. Absorption coefficient, scattering coefficient, and anisotropy factors of biocompatible fabrics were determined using integrating sphere spectrophotometry and an inverse Monte Carlo method. Fabric and reflective materials that exhibited highest attenuation of the blue light were selected to assemble a two-layer composite prototype. Prototypes were exposed to blue light emitted from a clinical source to ensure negligible temperature increase under clinically relevant exposure conditions. A protype blue-light phototherapy shield was made from two test materials, both of which provide sufficient light attenuation to provide patient protection. The testing method employed in this study may prove valuable for designing protective gear for a range of clinical procedures .