Photodynamic therapy with spatially resolved dual spectroscopic monitoring

摘要

An instrument for photodynamic therapy applies treatment light from a dye laser, white light, and ultraviolet fluorescence excitation light from an LED onto a lesion and surrounding areas in a time-multiplexed manner. The reflected white light is analyzed in a spectrometer to determine a correction for the dynamic optical spectral properties of the patient's tissue. Light emitted by fluorescence from the lesion and the surrounding areas is analyzed in another spectrometer, and the results are corrected in a computer, using the correction. An optical switch has been developed for the instrument, using a bistable solenoid and a sled.

主权项

1. An instrument for performing photodynamic therapy on a treatment area comprising a target lesion and a perilesion margin of a living patient, the instrument comprising:
light sources for providing treatment light for activating photoactive drugs within the treatment area, broadband light for creating a first reflected light spectrum from the target lesion and a second reflected light spectrum from the perilesion margin, and fluorescence excitation light for creating a first fluorescence from the target lesion and a second fluorescence from the perilesion margin; first optics for causing the treatment light, the broadband light and the fluorescence excitation light to be incident on the treatment area, whereby the broadband light is reflected from the treatment area and the fluorescence excitation light causes the treatment area to emit fluorescence; second optics for receiving the first reflected light spectrum from the target lesion and the second reflected light spectrum from the perilesion margin and the first fluorescence from the target lesion and the second fluorescence from the perilesion margin; a first spectrometer for receiving the first reflected light spectrum and the second reflected light spectrum from the second optics and for producing a signal representing the first reflected light spectrum and the second reflected light spectrum; a second spectrometer for receiving the first fluorescence and the second fluorescence from the second optics and for producing a signal representing the first fluorescence and the second fluorescence; and a computer, receiving the signals from the first and second spectrometers, for correcting the spectrum of the first fluorescence and the second fluorescence in accordance with the first reflected light spectrum and the second reflected light spectrum respectively and for providing the corrected first fluorescence and second fluorescence light spectrum for treatment optimization.