Multisensor probe for tissue identification

Abstract

A multisensor probe for continuous real-time tissue identification. The multisensor probe includes a tissue penetrating needle, a plurality of sensors useful in characterizing tissue and a position sensor to measure the depth of the needle into the tissue being diagnosed. The sensors include but are not limited to an optical scattering and absorption spectroscopy sensor, an optical coherence domain reflectometry sensor, an electrical impedance sensor, a temperature sensor, a pO 2 sensor, a chemical sensor and other sensors useful in identifying tissue. The sensors may take the form of a plurality of optical fibers extending through said needle. A retractable sheath may be disposed around the distal section of the needle to protect the needle when not in use. The sheath retracts when the probe is inserted into tissue and the position of the sheath relative to the needle may be measured to determine the needle's depth. Systems and methods for tissue identification are also provided.

1 . A multisensor probe for tissue identification comprising: 
 an elongate body having a distal section, a distal tip, and a lumen extending through said elongate body to said distal tip;    an optical scattering and absorption spectroscopy sensor configured to deliver and receive light from said distal tip of said elongate body; and    a position sensor incorporated into said probe and configured to measure the depth said distal tip is inserted into said tissue.    
     
     
         2 . The multisensor probe of  claim 1  further comprising a slideable sheath coaxially disposed over the distal section of said probe, said sheath being retractable from said distal section as said distal section of said elongate body is inserted into said tissue.  
     
     
         3 . The multisensor probe of  claim 1  wherein said position sensor is selected from the group consisting of an optical sensor, capacitive sensor, resistive sensor, laser ranging, sonic sensor, and a camera.  
     
     
         4 . The multisensor probe of  claim 1  wherein said position sensor is an optical encoder.  
     
     
         5 . The multisensor probe of  claim 2  wherein the position sensor is configured to read the position of said sheath relative to said elongate body.  
     
     
         6 . The multisensor probe of  claim 1  further comprising a handle for manipulating said multisensor probe.  
     
     
         7 . The multisensor probe of  claim 1  further comprising a marking switch to identify a location in said tissue as said distal section is inserted into said tissue.  
     
     
         8 . The multisensor probe of  claim 2  further comprising a spring to urge the sheath over the distal section such that when said probe is not in use, said sheath encloses said distal section of said elongate body.  
     
     
         9 . The multisensor probe of  claim 1  further comprising a electrical sensor for measuring electrical properties of said tissue.  
     
     
         10 . The multisensor probe of  claim 9  wherein the electrical sensor comprises a first electrically conducting element and a second electrically conducting element, said first and second electrically conducting elements extending to the distal tip of said elongate body.  
     
     
         11 . The multisensor probe according to  claim 10  wherein said first electrically conductive element is said elongate body.  
     
     
         12 . The multisensor probe of  claim 11  wherein the elongate body is a material selected from the group consisting of stainless steel, aluminum, titanium, gold, and silver.  
     
     
         13 . The multisensor probe of  claim 12  wherein said second electrically conductive element extends through said lumen.  
     
     
         14 . The multisensor probe of  claim 1  further comprising a memory device capable of storing useful information about the probe.  
     
     
         15 . The multisensor probe of  claim 1  further comprising an OCDR sensor, said OCDR sensor comprising an optical fiber extending through said lumen to said distal tip.  
     
     
         16 . The multisensor probe of  claim 15  wherein the optical scattering and absorption spectroscopy sensor includes at least three optical fibers extending through said lumen to said distal tip.  
     
     
         17 . The multisensor probe of  claim 16  wherein the elongate body has an outer diameter less than or equal to that of a 18 gauge needle.  
     
     
         18 . The multisensor probe of  claim 1  further comprising a P 02  sensor.  
     
     
         19 . The multisensor probe of  claim 18  further comprising a temperature sensor.  
     
     
         20 . The multisensor probe of  claim 19  wherein the temperature sensor and pO 2  sensor utilize a single fiber optic.  
     
     
         21 . The multisensor probe of  claim 1  wherein the distal tip of the elongate body is sharp.  
     
     
         22 . The multisensor probe of  claim 21  wherein the distal tip defines a plane and the plane forms an angle with an axis of said elongate body, said angle ranging from 30 to 70 degrees.  
     
     
         23 . A multisensor probe for tissue identification, said probe connectable to a controller via a cable, said probe comprising: 
 a needle having a distal tip and a lumen extending through said needle to said distal tip; and    a plurality of optical fibers extending from said controller, through said cable, through said lumen, to said distal tip of said needle when said probe is connected to said controller, wherein at least two of said plurality of optical fibers are optical scattering and absorption spectroscopy fiber optics and wherein at least one of said plurality of optical fibers is an OCDR fiber optic, and wherein a position sensor is incorporated into said probe, said position sensor adapted to measure depth the needle is inserted into the tissue.    
     
     
         24 . The multisensor probe of  claim 23  wherein the position sensor is a sensor selected from the group consisting of a resistive sensor and a linear optical encoder.  
     
     
         25 . The multisensor probe of  claim 23  having a conducting element extending through said lumen.  
     
     
         26 . The multisensor probe of  claim 23  further comprising a slideable sheath coaxially disposed over a distal section of said needle, said sheath being retractable from said distal section as said needle is inserted into said tissue.  
     
     
         27 . The multisensor probe of  claim 26  wherein the position sensor is configured to read the position of said sheath relative to said needle.  
     
     
         28 . A method for identifying tissue comprising: 
 manually inserting a multisensor probe as recited in  claim 1  into said tissue.    
     
     
         29 . A tissue detection system comprising: 
 a probe, said probe comprising a multisensor needle comprising a plurality of optical fibers, said probe further comprising a position sensor adapted to sense depth of the needle into said tissue; and    a controller configured to deliver and collect light through said plurality of optical fibers wherein at least one of said fibers is utilized as an OCDR sensor configured for measuring backscattered and reflected light as a function of depth into the tissue and wherein at least one said optical fibers is utilized for optical scattering and absorption.    
     
     
         30 . The system of  claim 29  further comprising at least one electrode for sensing electrical information about the tissue.  
     
     
         31 . The system of  claim 29  further comprising a sheath which retracts when the needle is inserted into said tissue.  
     
     
         32 . The system of  claim 31  wherein said position sensor measures said position of said sheath relative to said needle.  
     
     
         33 . A multisensor probe for tissue identification, said probe connected to a controller via a cable, said probe comprising: 
 a handle to manipulate said probe;    a needle joined to said handle, said needle having a distal section, a distal tip and a lumen extending through said needle to said distal tip;    a plurality of optical fibers extending from said controller, through said cable, through said lumen, to said distal tip of said needle;    a sheath slideably disposed around said distal section of said needle, said sheath being retractable into said handle when said distal section of said needle is inserted into said tissue; and    an optical position sensor coupled to said sheath to measure position of said retractable sheath relative to said handle, said position corresponding to the depth of insertion of said needle into said tissue.    
     
     
         34 . The multisensor probe of  claim 23  comprising a first light collecting fiber extending to a first point and a second light collecting fiber extending to second point wherein each of said first collecting fiber and second light collecting fiber is useful in optical scattering and absorption spectroscopy and wherein said first point is proximal to said second point.  
     
     
         35 . The multisensor probe of  claim 34  wherein said first point is proximal to said second point from 100 to 700 um.  
     
     
         36 . The multisensor probe of  claim 23  comprising a light collecting fiber having a center and a light emitting fiber having a center wherein said center of said light collecting fiber is separated from said center of said light emitting fiber by 175 to 500 um.  
     
     
         37 . The multisensor probe of  claim 36  wherein said center of said light collecting fiber is separated from said center of said light emitting fiber by 300 to 500 um.  
     
     
         38 . The multisensor probe of  claim 10  wherein said elongate body is made of a conducting polymer.  
     
     
         39 . The multisensor probe of  claim 14  wherein said memory device is configured to detect whether said probe has been previously used in a tissue identification procedure.  
     
     
         40 . The multisensor probe of  claim 39  wherein said memory device is configured to prevent said probe from being used more than once.  
     
     
         41 . The multisensor probe of  claim 1  wherein said position sensor is a resistive sensor.  
     
     
         42 . The multisensor probe of  claim 1  wherein said position sensor is configured to detect movement of a component of the probe that is displaced as said distal tip is inserted into said tissue.  
     
     
         43 . The multisensor probe of  claim 16  wherein said optical fibers include at least one multimode fiber and at least one single mode fiber.  
     
     
         44 . A multisensor probe for tissue identification comprising: 
 a handle;    an elongate body extending from the handle, said elongate body having a distal section, a distal tip, and a lumen extending through said elongate body to said distal tip;    an optical scattering and absorption spectroscopy sensor configured to deliver and receive light from said distal tip of said elongate body; and    a position sensor incorporated into said handle and configured to measure the depth said distal tip is inserted into said tissue.    
     
     
         45 . The multisensor probe of  claim 1 , wherein the position sensor is configured to generate a measurement of the depth said distal tip is inserted into said tissue.  
     
     
         46 . The multisensor probe of  claim 1 , wherein the position sensor comprises an electronic position sensor.  
     
     
         47 . The multisensor probe of  claim 23 , wherein the position sensor is configured to generate a measurement of the depth said distal tip is inserted into said tissue.  
     
     
         48 . The multisensor probe of  claim 23 , wherein the position sensor comprises an electronic position sensor.  
     
     
         49 . The method of  claim 28 , further comprising electronically measuring the depth the distal tip of the probe is inserted into the tissue.  
     
     
         50 . The multisensor probe of  claim 44 , wherein the position sensor is adapted to generate a measurement of the depth said distal tip is inserted into said tissue.  
     
     
         51 . The multisensor probe of  claim 44 , wherein the position sensor comprises an electronic position sensor.