Light-emitting Fabrics for Photodynamic Therapy

A homogeneous and reproducible fluence delivery rate during clinical photodynamic therapy (PDT) plays a determinant role in preventing under- or overtreatment. PDT in dermatology has been carried out with a variety of light sources delivering a broad range of light doses. Owing to the complexities of the human anatomy, these light sources do not deliver a uniform light distribution to the skin. The development of flexible light sources would considerably improve the homogeneity of light delivery. The integration of plastic optical fibres (POF) into textile structures could offer an interesting alternative.We developed a light-emitting fabric (LEF) using POF and polyester yarns. Predetermined POF macrobending leads to side emission of light when the critical angle is exceeded. Therefore, a specific pattern based on different satin weaves was developed to improve light emission homogeneity and to correct the decrease in side-emitted radiation intensity along the POF. The fluence rate of the LEF was 18±2.5mWcm^-2. Optical losses were very low. Temperature elevation was 0.6°C after 10min of illumination. Our LEF meets the basic requirements for PDT: homogeneous light distribution and flexibility. It also confirms that large (500cm²) LEFs can be easily produced by textile manufacturing processes.