Compact and fully automated system for monitoring photodynamic therapy, based on two LEDs and a single CCD

• Published in: Laser physics letters Vol. 12; no. 11; pp. 115602 - 115607
• Main Authors: Kleshnin, M S, Fiks, I I, Plekhanov, V I, Gamayunov, S V, Turchin, I V
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.11.2015
• Subjects: fluorescence imaging; photobleaching; photodynamic therapy; photosensitizer
• ISSN: 1612-2011; 1612-202X
• DOI: 10.1088/1612-2011/12/11/115602

Photodynamic therapy is one of the most promising methods for the treatment of oncological, inflammatory and degenerative diseases of the skin. This technique is based on light irradiation of a photosensitizer that has been injected into the patient's body prior to the procedure, with determination of the efficacy of treatment requiring proper assessment of the drug concentration in the tissue lesion and the extent of sensitizer photobleaching during irradiation. We have developed a compact and low cost device based on a fluorescence imaging for localizing the tumor in the patient's body, tracking the position of the tissue lesion during involuntary movements of the patient, estimating accumulation of the sensitizer in the tumor relative to the surrounding tissues and monitoring photobleaching of the sensitizer during laser irradiation. The system that has been created is compatible with any therapeutic laser and includes a single CCD camera and two LEDs, one in the excitation band and the other in the emission band of the 'Photoditazin' sensitizer. In this letter we also present the test results of the device in model experiments and in preliminary clinical trials. The results obtained clearly show the efficacy of the system for monitoring sensitizer photobleaching during photodynamic therapy.