Development of a new multi-mode NIR laser system for photodynamic therapy

Abstract

Photodynamic Therapy (PDT) has been used in various fields especially in cancer treatment. In PDT, designing a light source has vital importance in order to achieve a successful treatment. Among the light sources, Lasers are important candidates for their precise wavelengths to activate the photosensitizers (PS), coherent nature and fiber-coupled usage. In order to achieve perfect PDT treatment, the Laser light sources needs to be embedded with high stability current, temperature controllers and closed loop control systems. In this study, a novel Multi-mode PDT Laser system (MPTL) was developed with four different radiation modes. Importantly, Super Pulse Mode (SPM) was implemented for the first time among the PDT Laser systems in the open literature to minimize the thermal damage to the target tissue. The proposed system achieved high optical output stability by precise current and temperature control of the Laser resonator. The MPTL achieved high optical output stability (+/- 1mW) in the range of 0-1500 mW, high wavelength stability (+/- 1nm) at 635 nm, and high temperature stability (+/- 0.2 degrees C) in all radiation modes. The MPTL system with super pulse mode can be safely used for wide range of PDT clinical applications.