Fluorescence imaging system for an operating room

Abstract

Fluorescence imaging system for an operating theatre, comprising a device illuminating the operating theatre and emitting a white light, and a fluorescence imaging device. Said fluorescence imaging device comprises a light source emitting radiation for excitation of a fluorescent marker in a range of emission wavelengths of between 600 and 900 nm. The light emitted by the illuminating device is filtered by a low-pass filter, of which the cut-off wavelength is below the emission range of the fluorescent marker, but is nonetheless able to show an increase or fluctuations in the attenuation for wavelengths above the emission range of the fluorescent marker, the product of the attenuation of the filter of the detector and of the attenuation of the low-pass filter of the illuminating device leading to an attenuation by a factor of at least 106.

Description

FIELD OF THE INVENTION[0001]The present invention concerns a fluorescence imaging system for an operating room comprising a device illuminating the operating room and a fluorescence medical imaging device.BACKGROUND OF THE INVENTION[0002]Fluorescence medical imaging is a promising technique in particular for surgical procedures for the purpose of guiding a surgeon's action.[0003]This technique is based on administering a substance to a patient that contains a fluorescent marker e.g. for observation of a target organ or tissue which is to undergo surgical procedure, or for observation of a flow monitored by the marker.[0004]By means of the presence of the fluorescent marker in or close to the target organ or tissue, the illumination of the region of the patient comprising the organ has the effect of exciting the marker which in turn emits radiation at a wavelength slightly longer than the excitation wavelength.[0005]The chief applications are in the Near InfraRed (NIR) i.e. the excit...

AI Technical Summary

Benefits of technology

The detector in this patent has a feature that eliminates background noise and other interference caused by bright light. This allows the detector to get more sensitive and produce images with more detail. The illuminating device provides continuous lighting, which is helpful for certain applications.

Problems solved by technology

If not, these wavelengths would be detected by the detector D and would generate noise on the fluorescence image, harming the quality thereof.

Yet at 150 kLux, even a very slight leakage of light from the operating room lighting in the range of wavelengths measured by the detector through its filter is able to limit the quality of fluorescence images.

In addition, requirements in terms of quality of surgical lighting are drastic.

However the switching-off of lighting ill lends itself to surgical procedure.

However, with all the above-described devices a fluorescent background can be seen in the images obtained which reduces the contrast with the fluorescence emitted by the organ or tissue of interest.

However, for the wavelengths of the near infrared under consideration, autofluorescence is negligible and cannot alone account for the observed fluorescent background.

Another hypothesis to explain this unsatisfactory quality of images could be insufficient filtering of the excitation light source.

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