Irradiance uniformity optimization for a photodynamic therapy treatment device with 3D scanner

Significance: The light dose in photodynamic therapy (PDT) has a considerable influence on its treatment effect, and irradiance uniformity is an issue of much concern for researchers. However, achieving intelligent and personalized dosimetry adjustments remains a challenge for current PDT instruments. Aim: To meet the requirements of intelligent and personalized dosimetry adjustments for the light dose on an irregular surface, a new PDT device with its optimal control method is proposed. Approach: This research introduces a new PDT device that includes a 3D scanner, a light-emitting diode (LED) array, and a computer. The 3D scanner is proposed to generate the point cloud of the lesion and the LED array light source, and obtain the relative position and rotation parameters between them. Then, an image segmentation algorithm is used to segment the lesion point cloud into several cluster regions. Last, the current of each LED unit is adjusted separately to achieve the expected irradiance on each cluster. Results: Compared with the general light source, the optimized light source increases the effective irradiance area by 9% to 15% and improves its uniformity by 1/49 % on a human port-wine stain head model. Conclusions: The device and its optimal method may be used for optimizing the light dosimetry to realize intelligent and personalized treatment.