Surgical visualization and medical imaging devices and methods using near infrared fluorescent polymers

Abstract

A surgical visualization and medical imaging device and related computer based imaging methods and systems are disclosed. The surgical devices of the present invention use indocyanine green dye combined with a plastic, and are used in enhanced surgical imaging in applications such as robotically assisted surgeries. A near infrared light source, such as an 805 nm laser, may be used to excite the surgical device so that the device emits 835 nm light. Both the excitation and emission wavelengths penetrate tissue and blood, and provide enhanced imaging of surgical procedures. The resulting fluorescence image allows a user to readily determine relative tissue depth, to identify tissue inhomogeneity, to detect masses or tissue irregularities, to pinpoint anatomical holes, and to visualize tears.

What is claimed is: 
     
         1 . A method of visualizing tissue during a surgical procedure, comprising the steps of:
 providing a medical device having a body formed from a polymer, a near infrared fluorescent dye embedded in the polymer, and a fluorescence enhancer embedded in the polymer;   positioning the medical device under an amount of tissue in a surgical site and oppositely from a near infrared fluorescence detector;   exciting the medical device with an amount of near infrared radiation so that the body will emit fluorescence at a level that is sufficient to pass through the amount of tissue in the surgical site and to reveal any features of the amount of tissue;   detecting the fluorescence emitted by the body; and   displaying the fluorescence emitted by the body so that the features of the amount of tissue are visible.   
     
     
         2 . The method of  claim 1 , wherein the amount of fluorescence emitted by the device penetrates the amount of tissue to a depth of about ten millimeters. 
     
     
         3 . The method of  claim 2 , wherein the step of displaying the fluorescence emitted by the body so that the features of the amount of tissue are visible comprises displaying the fluorescence in combination with the visual spectrum. 
     
     
         4 . The method of  claim 3 , wherein the step of exciting the medical device with an amount of near infrared radiation includes modulation of at least one of an intensity, an angle of incidence, and a duty cycle of a source of near infrared radiation. 
     
     
         5 . The method of  claim 1 , wherein the body is the head of a bowel sizer. 
     
     
         6 . The method of  claim 1 , wherein the body is the head of a vaginal manipulator. 
     
     
         7 . The method of  claim 1 , wherein the body is a cup of a uterine manipulator. 
     
     
         8 . The method of  claim 1 , wherein the polymer is selected from the group consisting of polycaprolactone, acrylonitrile butadiene styrene, polytetrafluoroethylene, and polycarbonate. 
     
     
         9 . The method of  claim 1 , wherein the amount of near infrared dye embedded in the polymer is present in a concentration of 50 parts per million. 
     
     
         10 . The method of  claim 1 , wherein the amount of fluorescence enhancer embedded in the polymer is an inorganic compound. 
     
     
         11 . The method of  claim 1 , wherein the body has a predetermined volume that is formed from and filled throughout by the polymer having the embedded near infrared fluorescent dye and the embedded fluorescence enhancer. 
     
     
         12 . The method of  claim 1 , wherein the step of displaying the fluorescence emitted by the body so that the features of the amount of tissue are visible comprises the steps of:
 creating a coordinate map of a surgical field of view;   assigning a coordinate to each location on the coordinate map;   receiving brightness values for each coordinate;   assigning relative tissue depth values for each coordinate based on the received brightness values;   assigning tissue density values for each coordinate based on the received brightness values;   creating a virtual image of the surgical field of view using the relative tissue depth values for each coordinate and the tissue density values for each coordinate;   adding an image of the surgical field of view to the virtual image of the surgical field of view; and   displaying the image of the surgical field of view with the virtual image of the surgical field of view on a monitor.