Methods and Apparatus for Locating Body Vessels and Occlusions in Body Vessels

Abstract

Methods and apparatus employed to locate body vessels and occlusions in body vessels finding particular utility in cardiac surgery, particularly minimally invasive cardiac surgery to locate cardiac arteries and occlusions in cardiac arteries are disclosed. An elongated vessel lumen probe incorporating a lumen probe element at or near the elongated vessel lumen probe distal end is advanced into the vessel lumen. A vessel surface probe manipulated by the surgeon and having a surface probe element sensor is employed to detect the lumen probe element and to follow the progress of the vessel lumen probe element as it approaches and is advanced through or is blocked by an occlusion. In the location of a coronary artery, the surface probe element sensor is moved about against the epicardium over the suspected location of the artery of interest until a surface probe element sensor of the present invention at the surface probe distal end interacts with the lumen probe element of the vessel lumen probe.

1 . A method of identifying the course of a body vessel that is hidden from direct view in a surgical field by body tissue overlying the vessel wall surrounding the vessel lumen comprising:
 surgically exposing at least a portion of body tissue overlying the vessel wall;   introducing a vessel lumen probe having a lumen probe element at or near a vessel lumen probe distal end into the vessel lumen; and   applying a surface probe element sensor of a vessel surface probe over the body tissue overlying the vessel wall, the surface probe element sensor adapted to provide a proximity indicating signal indicating the degree of proximity of the surface probe element sensor to the lumen probe element, whereby the location of the vessel lumen is determinable as a function of the relative strength of the signal.   
   
   
       2 . A system for identifying the course of a body vessel that is hidden from direct view in a surgical field by body tissue overlying the vessel wall surrounding the vessel lumen comprising:
 a vessel lumen probe having a lumen probe element at or near a vessel lumen probe distal end adapted to be introduced into the vessel lumen; and   a vessel surface probe having a surface probe element sensor adapted to be applied and moved about over the body tissue overlying the vessel wall, the surface probe element sensor adapted to provide a proximity indicating signal indicating the degree of proximity of the surface probe element sensor to the lumen probe element, whereby the location of the vessel lumen is determinable as a function of the relative strength of the signal.   
   
   
       3 . The system of  claim 2 , wherein the vessel lumen probe further comprises means for sweeping the lumen probe element around the vessel wall within the vessel lumen while monitoring the indication of proximity. 
   
   
       4 . The system of  claim 2 , wherein the lumen probe element comprises a metallic element and the surface probe element sensor comprises a metal detector coil assembly, and the applying step further comprises:
 energizing the metal detector coil assembly to develop a signal responsive to the detection of the metallic element through the vessel wall and body tissue overlying the vessel wall.   
   
   
       5 . The system of  claim 2 , wherein the lumen probe element comprises a lumen probe magnet, and the surface probe element sensor comprises a magnet, the lumen probe magnet and surface probe magnet selected in polarity to enable magnetic attraction of the lumen probe element and lumen probe distal end toward the vessel wall in proximity to the surface probe element. 
   
   
       6 . The system of  claim 2 , wherein the vessel lumen probe comprises an elongated probe body having a probe body lumen extending the length of the probe body to a distal lumen opening, the lumen probe element comprises a lumen probe magnet, and the surface probe element sensor comprises a magnet, the lumen probe magnet and surface probe element sensor selected in polarity to enable magnetic attraction of the lumen probe magnet and lumen probe distal end toward the vessel wall in proximity to the surface probe magnet, the probe body lumen enabling introduction of a device or material to or into the interior vessel wall. 
   
   
       7 . The system of  claim 6 , wherein the probe body is formed of a probe body proximal section joined to a probe body distal section by a joint enabling rotation of the probe body distal section with respect to the probe body proximal section, the lumen probe magnet is mounted to the probe body distal section along one side of the probe body distal section, and the probe lumen distal end opening is substantially aligned to the one side of the probe body distal section, whereby the probe body distal section is rotatable at the joint under the magnetic field attraction of the lumen probe magnet toward the surface probe magnet and the probe lumen distal end opening is directed toward the vessel wall that the one side of the probe body distal section faces. 
   
   
       8 . The system of  claim 7 , further comprising an elongated wire extending between wire proximal and distal ends and sized to fit into and be advanced through the probe body lumen of the probe body proximal and distal sections to locate the wire distal end at or extending through the vessel wall. 
   
   
       9 . The system of  claim 2 , wherein the lumen probe element comprises a magnet, and the surface probe element sensor comprises a magnet, whereby magnetic attraction or repulsion force between the magnets provides the proximity indicating signal. 
   
   
       10 . The system of  claim 2 , wherein the lumen probe element comprises an electrically conductive, vessel probe electrode, and the surface probe element sensor comprises an electrically conductive, surface probe electrode, and further comprising:
 means for applying electrical energy between the electrically conductive, vessel probe electrode and the electrically conductive, surface probe electrode; and   means for measuring the impedance between the electrically conductive, vessel probe electrode and the electrically conductive, surface probe electrode to develop an impedance signal related to the proximity of the electrically conductive, vessel probe electrode to the electrically conductive, surface probe electrode.   
   
   
       11 . The system of  claim 2 , wherein:
 the surface probe element sensor comprises an electrically conductive, surface probe electrode; and   the vessel lumen probe comprises an elongated probe sheath enclosing a sheath lumen extending from a probe sheath proximal end to a distal lumen opening near a probe sheath distal end and an elongated probe wire sized to fit within the sheath lumen, the probe wire having an electrically conductive, vessel probe electrode adapted to move with respect to the distal lumen opening through manipulation of the probe wire to extend the vessel probe electrode toward the vessel wall;   
     and further comprising:
 means for applying electrical energy between the electrically conductive, vessel probe electrode and the electrically conductive, surface probe electrode; and 
 means for measuring the impedance between the electrically conductive, vessel probe electrode and the electrically conductive, surface probe electrode to develop an impedance signal related to the proximity of the electrically conductive, vessel probe electrode to the electrically conductive, surface probe electrode. 
 
   
   
       12 . The system of  claim 2 , wherein:
 the vessel lumen probe comprises an elongated light transmitting and emitting light pipe having a light pipe proximal end adapted to be coupled to a light source and a light pipe distal end from which light source light is emitted; and   the surface probe element sensor comprises a photosensor that responds to the frequency of light emitted by the light emitter and transmitted through the vessel wall and body tissue overlying the vessel wall.   
   
   
       13 . The system of  claim 2 , wherein:
 the vessel lumen probe comprises:
 an elongated probe sheath enclosing a sheath lumen extending from a probe sheath proximal end to a distal lumen opening near a probe sheath distal end; and 
 an elongated light transmitting and emitting light pipe having a light pipe proximal end adapted to be coupled to a light source and a light pipe distal end from which light source light is emitted, the light transmitting and emitting light pipe sized to be extended through the sheath lumen to dispose the light pipe distal end in proximity with the vessel wall within the vessel lumen; and 
   the surface probe element sensor comprises a photosensor that responds to the frequency of light emitted from the light pipe distal end and transmitted through the vessel wall and body tissue overlying the vessel wall.   
   
   
       14 . The system of  claim 2 , further comprising a marker adapted to be applied to the body tissue overlying the vessel wall at the determined location to mark the determined location. 
   
   
       15 . The system of  claim 2 , wherein the vessel surface probe further comprises a marker adapted to be applied to the body tissue overlying the vessel wall at the determined location to mark the determined location. 
   
   
       16 . The system of  claim 2 , further comprising a marker containing marking ink adapted to be applied to the body tissue overlying the vessel wall at the determined location to dispense marking ink to mark the determined location. 
   
   
       17 . The system of  claim 2 , wherein the vessel surface probe further comprises a marker containing marking ink adapted to be applied to the body tissue overlying the vessel wall at the determined location to dispense marking ink to mark the determined location. 
   
   
       18 . A system for identifying the course of a coronary artery vessel in a surgical field that is hidden from direct view by body tissue overlying the vessel wall surrounding the vessel lumen comprising:
 a vessel lumen probe having a lumen probe element at or near a vessel lumen probe distal end adapted to be introduced through the arterial system and into the arterial lumen of a coronary artery; and   a vessel surface probe having a surface probe element sensor adapted to be applied and moved about over the tissue overlying the epicardium and arterial wall, the surface probe element sensor adapted to provide a proximity indicating signal indicating the degree of proximity of the surface probe element sensor to the lumen probe element, whereby the location of the path of the coronary artery and any obstruction of the coronary artery is determinable as a function of the relative strength of the signal.   
   
   
       19 . The system of  claim 18 , wherein the vessel lumen probe further comprises means for sweeping the lumen probe element around the arterial wall within the coronary artery while monitoring the indication of proximity. 
   
   
       20 . The system of  claim 18 , further comprising a marker adapted to be applied to the tissue overlying the arterial wall at the determined location to mark the determined location.