An apparatus and method for imaging diseases in tissue are presented. The apparatus employs a light source for producing excitation light to excite the tissue to generate autofluorescence light and for producing illumination light to generate reflected and back scattered light (remittance light) from the tissue. Optical sensors are used to receive the autofluorescence light and the remittance light to collect an autofluorescence light image and a remittance light image. A filter acts to integrate the autofluorescence image over a range of wavelengths in which the autofluorescence intensity for normal tissue is substantially different from the autofluorescence intensity for diseased tissue to establish an integrated autofluorescence image of the tissue. The remittance light image provides a background image to normalize the autofluorescence image to account for image non-uniformity due to changes in distance, angle and illumination intensity. A monitor displays the integrated autofluorescence image and the remittance light image to produce a normalized image in which diseased tissue is distinguishable from normal tissue. The optical sensor can be installed adjacent the end of an endoscope probe inserted into a body cavity. A method for imaging diseased tissue using an integrated fluorescence image and a normalizing remittance image is also disclosed.

Apparatus and method for imaging diseased tissue using integrated autofluorescence

Apparatus for imaging diseases in tissue comprising a light source for generating excitation light that includes wavelengths capable of generating characteristic autofluorescence for abnormal and normal tissue. A fibreoptic illuminating light guide is used to illuminate tissue with light that includes at least the excitation light thereby exciting the tissue to emit the characteristic autofluorescence. An imaging bundle collects emitted autofluorescence light from the tissue. The autofluorescence light is filtered into spectral bands in which the autofluorescence intensity for abnormal tissue is substantially different from normal tissue and the autofluorescence intensity for abnormal tissue is substantially similar to normal tissue. An optical system is used to intercept the filtered autofluorescence light to acquire at least two filtered emitted autofluorescence images of the tissue. The acquired images are displayed in real time on a display monitor in such a manner as to delineate abnormal and normal tissue.

Endoscopic imaging system for diseased tissue

A catheter for diagnosing and performing an interventional procedure on tissue has an elongated catheter shaft, and optical fibers, extending through the catheter shaft, for transmitting light to tissue located at a distal end of the catheter and conveying light back from the tissue for analysis by a spectroscopic diagnosis system to determine whether an interventional procedure should be performed on the tissue. An interventional device is located at the distal end of the catheter for engaging tissue diagnosed by the spectroscopic diagnosis system in order to perform the interventional procedure on the tissue. An assembly for imaging and performing an interventional procedure on tissue has an endoscope in combination with an endoscopically insertable catheter having an ultrasound imaging device for imaging a tissue structure located at a distal end of the endoscope so as to enable the depth of penetration of the tissue structure to be displayed, and an endoscopically insertable interventional device for engaging the tissue structure imaged by the ultrasound imaging device.

Diagnosing and performing interventional procedures on tissue in vivo

Excitation light for normal light observation with wavelengths in the visible spectrum, which is output from a lamp, and excitation light with wavelengths in the infrared spectrum for exciting a fluorescent substance characteristic of being accumulated readily in a lesion are irradiated simultaneously to a living tissue, to which the fluorescent substance has been administered, through an endoscope. Fluorescence components are separated from light stemming from the living tissue by means of a separator such as a dichroic mirror, introduced to a first imaging device, and then imaged. Light components with wavelengths in the visible spectrum are introduced to a second imaging device and then imaged. Signals representing the images are subjected to signal processing, whereby a video signal is produced. For better diagnosis, two images are displayed while, for example, one of the images is superimposed on the other.

Fluorescent endoscope system enabling simultaneous normal light observation and fluorescence observation in infrared spectrum

A system for detecting cancerous or precancerous lesions directs light produced from a mercury arc lamp (100) into an illumination guide (106) of an endoscope. Autofluorescence light produced by the tissue under examination is divided into red and green spectral bands by a dichroic mirror (120). Light in the red and green spectral band is applied to a pair of image intensified CCD cameras (126, 130). The output of the camera that receives light in the red spectral band is coupled to a red video input of a color video monitor (150). Light produced by the camera that receives light in the green spectral band is coupled to the blue and green video inputs of the video monitor. The system produces a false color display, whereby healthy tissue appears cyan in color and cancerous or precancerous lesions appear reddish in color. The image displayed allows the operator to see the lesions within the context of the underlying tissue structures. The color contrast is adjustable to account for the autofluorescence property changes from patient to patient and from location to location.

Imaging system for detecting diseased tissue using native fluorescence in the gastrointestinal and respiratory tract

An object is illuminated sequentially with light of wavelengths in respective narrow bands through a light guide in an electronic endoscope provided with an imaging device. The picture images are photoelectrically converted by the imaging device and are temporarily stored respectively in memories. The spectral distribution characteristics of the object are calculated by using spectral distribution calculating data and are displayed on a display.

Kazunari Nakamura

Papers

Spectral diagnosing apparatus with endoscope