Development and Error Analysis of a Novel Robotic System for Photodynamic Therapy

Photodynamic therapy has the potential to not only treat tumors directly but also to reduce incidental damage caused by large surgical margins and radiation therapy. In this study, a novel robotic system of delivering light was developed using a cartesian robot. Human input was limited to a computer input and no physical positioning of the light delivery system was required during testing. Error analysis was conducted to ensure the system's applicability to a clinical environment. Error involved in both the outlining and coverage of the targeted areas was examined. The average outlining error and standard deviation were 0.23 +/- 0.16mm, and the coverage time error was below 4%. These results indicate that a robotic light delivery system for photodynamic therapy can consistently provide light delivery with sub-millimeter errors when testing with ex-vivo phantoms.