Vascular image co-registration

Abstract

A system and method for providing a vascular image are disclosed wherein a single composite display simultaneously provides a first view of a patient including an angiogram image and a second view including an intravascular image rendered from information provided by an imaging probe mounted on a distal end of a flexible elongate member. A cursor, having a position derived from image information provided by a radiopaque marker proximate the imaging probe, is displayed within the angiogram image to correlate the position of the imaging probe to a presently displayed intravascular image and thus provide an easily discernable identification of a position within a patient corresponding to a currently displayed intravascular image. The resulting composite display simultaneously provides: an intravascular image that includes information about a vessel that is not available from an angiogram and a current location within a vessel of a source of intravascular image data from which the intravascular image is rendered.

What is claimed is: 
     
       1. A system for acquisition and co-registered display of intravascular information, comprising:
 an imaging flexible elongate member having a proximal end and a distal end;   an imaging probe located near the distal end of the flexible elongate member, and configured to obtain information for generating an image of a vessel;   a radiopaque marker located near the imaging probe;   a first memory for storing angiogram image data;   a second memory for storing intravascular image data derived from information obtained by the imaging probe;   a third memory for storing radiopaque marker image data, distinct from the angiogram image data, the radiopaque marker image data being derived from information obtained from a fluoroscopic imaging device;   a display processor configured to retrieve and combine data from the first memory, the second memory and the third memory, and further configured to render a composite image including:
 an enhanced radiological image derived from the angiogram image data comprising a superimposition of at least a portion of the angiogram data and the radiopaque marker image data and providing a location of the radiopaque marker based upon an actual location during active fluoroscopy and an estimated location during inactive fluoroscopy, 
 an intravascular image element corresponding to the intravascular image data, wherein the enhanced radiological image and the intravascular image element are displayed proximate each other; and 
 a cursor, displayed upon the enhanced radiological image, indicative of a location of the imaging probe while acquiring data for the intravascular image element presently displayed on the composite image, said cursor having a position that is based at least in part on third data derived from the radiopaque marker image data stored in the third memory; 
   
       wherein the display processor is further configured to calculate an error function based on a difference between the estimated location of the radiopaque marker and the actual location of the radiopaque marker and wherein the display processor further configured to utilize the error function to correct the estimated location of the radiopaque marker for the preceding period of inactive fluoroscopy. 
     
     
       2. The system of  claim 1  wherein the flexible elongate member is a catheter. 
     
     
       3. The system of  claim 1  wherein the imaging probe comprises an ultrasound device. 
     
     
       4. The system of  claim 3  wherein the ultrasound device is a side-firing intravascular ultrasound transducer assembly. 
     
     
       5. The system of  claim 4  wherein the side-firing intravascular ultrasound transducer assembly comprises an array of transducer elements. 
     
     
       6. The system of  claim 5  wherein the array of transducer elements are linearly arranged along a lengthwise axis of the flexible elongate member. 
     
     
       7. The system of  claim 5  wherein the array of transducer elements are curvilinearly arranged about a lengthwise axis of the flexible elongate member. 
     
     
       8. The system of  claim 5  wherein the array of transducer elements are circumferentially arranged about a lengthwise axis of the flexible elongate member. 
     
     
       9. The system of  claim 3  wherein the ultrasound device comprises a Doppler transducer. 
     
     
       10. The system of  claim 9  wherein the flexible elongate member comprises a guidewire. 
     
     
       11. The system of  claim 1  wherein the flexible elongate member is a guidewire and the imaging probe comprises a pressure sensor. 
     
     
       12. The system of  claim 1  wherein the radiopaque marker comprises a cylindrical marker band. 
     
     
       13. The system of  claim 1  wherein the radiopaque marker comprises at least one partially complete cylindrical marker band. 
     
     
       14. The system of  claim 13  wherein the radiopaque marker comprises two semi-cylindrical marker bands. 
     
     
       15. The system of  claim 14  wherein the two semi-cylindrical marker bands are skewed in relation to one another along a lengthwise axis of the flexible elongate member. 
     
     
       16. The system of  claim 15  wherein the display processor further comprises an orientation determination function for determining a relative orientation of the imaging probe within the vessel based upon at least a relative size and position of the two semi-cylindrical marker bands in relation to one another. 
     
     
       17. The system of  claim 1  wherein the third data is derived from user-specified points. 
     
     
       18. The system of  claim 1  wherein the third data is derived by automated processes that determine a position of the radiopaque marker within a field of view. 
     
     
       19. The system of  claim 18  wherein the automated processes utilize image pattern recognition to determine the position. 
     
     
       20. The system of  claim 1  wherein the third data is derived from a combination of manual user input and automated calculations. 
     
     
       21. The system of  claim 20  wherein the automated calculations include determination of a predicted path of the imaging probe. 
     
     
       22. The system of  claim 1  wherein the display processor further comprises a bookmark function enabling a user to designate particular images of interest in a stored set of images containing at least the intravascular image element. 
     
     
       23. The system of  claim 1  wherein the enhanced radiological image includes a calculated path of the imaging probe. 
     
     
       24. The system of  claim 1  wherein the display processor further comprises-a slider function associated with the cursor that enables a user to reposition the cursor to a point of interest on the enhanced radiological image through a user interface control, and in response displays a particular instance of the intravascular image element associated with the point of interest. 
     
     
       25. The system of  claim 1 , wherein the estimated location is based at least in part on a calculated path of the imaging probe and wherein the calculated path is updated based on the error function that is calculated based on a difference between the estimated location of the radiopaque marker and the actual location of the radiopaque marker. 
     
     
       26. A method for acquiring and displaying intravascular information in a system including an imaging flexible elongate member having a proximal end and a distal end, an imaging probe located near the distal end of the flexible elongate member, and configured to obtain information for generating an image of a vessel, and a radiopaque marker located near the imaging probe, the method comprising the steps of:
 storing angiogram image data in a first memory;   storing intravascular image data derived from information obtained by the imaging probe in a second memory;   storing radiopaque marker image data, distinct from the angiogram image data, in a third memory, the radiopaque marker image data being derived from information obtained from a fluoroscopic imaging device;   combining, by a display processor, data retrieved from the first memory, the second memory and the third memory to render a composite image including:
 an enhanced radiological image derived from the angiogram image data comprising a superimposition of at least a portion of the angiogram data and the radiopaque marker data and providing a location of the radiopaque marker based upon an actual location during active fluoroscopy and an estimated location during inactive fluoroscopy, and 
 an intravascular image element corresponding to the intravascular image data, wherein the enhanced radiological image and the intravascular image element are displayed proximate each other; and 
   displaying a cursor upon the enhanced radiological image, indicative of a location of the imaging probe while acquiring data for the intravascular image element presently displayed on the composite image, said cursor having a position that is based at least in part on third data derived from the radiopaque marker image data previously stored in the third memory;   wherein the estimated location is based on a calculated path of the imaging probe, and wherein an error function is calculated based on a difference between the estimated location of the radiopaque marker and the actual location of the radiopaque marker when active fluoroscopy is resumed after inactive fluoroscopy and wherein the error function is utilized to correct the calculated path.   
     
     
       27. The method of  claim 26  wherein the flexible elongate member is a catheter. 
     
     
       28. The method of  claim 26  wherein the imaging probe comprises an ultrasound device. 
     
     
       29. The method of  claim 28  wherein the ultrasound device comprises a Doppler transducer. 
     
     
       30. The method of  claim 26  wherein the flexible elongate member is a guidewire and the imaging probe comprises a pressure sensor. 
     
     
       31. The method of  claim 26  wherein the radiopaque marker comprises two semi-cylindrical marker bands that are skewed in relation to one another along a lengthwise axis of the flexible elongate member and wherein the method comprises determining an orientation of the imaging probe based upon at least a relative size and position of the two semi-cylindrical marker bands in relation to one another. 
     
     
       32. The method of  claim 26  wherein the third data is derived from user-specified points. 
     
     
       33. The method of  claim 26  wherein the third data is derived by automated processes that determine a position of the radiopaque marker within a field of view. 
     
     
       34. The method of  claim 26  wherein the third data is derived from a combination of manual user input and automated calculations. 
     
     
       35. The method of  claim 34  wherein the automated calculations determine a predicted path of the imaging probe. 
     
     
       36. The method of  claim 26  further comprising storing a user-designated set of particular images of interest in a stored set of images containing at least the intravascular image element. 
     
     
       37. The method of  claim 26  further comprising incorporating a calculated path of the imaging probe within the enhanced radiological image. 
     
     
       38. The method of  claim 26  further comprising providing a slider function associated with the cursor that enables a user to reposition the cursor to a point of interest on the enhanced radiological image through a user interface control, and in response display a particular instance of the intravascular image element associated with the point of interest. 
     
     
       39. The method of  claim 26 , wherein the calculated path is calculated using a first multiplication coefficient if the imaging probe is being pulled through the vessel and a second multiplication coefficient if the imaging probe is being pushed through the vessel. 
     
     
       40. A system for acquisition and co-registered display of intravascular information, comprising:
 an imaging flexible elongate member having a proximal end and a distal end;   an imaging probe located near the distal end of the flexible elongate member, and configured to obtain information for generating an image of a vessel;   a radiopaque marker located near the imaging probe;   a first memory portion for storing angiogram image data;   a second memory portion for storing intravascular image data derived from information obtained by the imaging probe;   a third memory portion for storing radiopaque marker image data, the radiopaque marker image data being derived from information obtained from a fluoroscopic imaging device;   a display processor configured to retrieve and combine data from the first memory portion, the second memory portion and the third memory portion, and further configured to render a composite image including:
 an enhanced radiological image derived from the angiogram image data comprising a superimposition of at least a portion of the angiogram data and the radiopaque marker image data and providing a location of the radiopaque marker based upon an actual location during active fluoroscopy and an estimated location during inactive fluoroscopy, wherein an error function is calculated based on a difference between the estimated location of the radiopaque marker and the actual location of the radiopaque marker when active fluoroscopy is resumed after inactive fluoroscopy and wherein the error function is utilized to correct the estimated location of the radiopaque marker for the preceding period of inactive fluoroscopy, 
   an intravascular image element corresponding to the intravascular image data, wherein the enhanced radiological image and the intravascular image element are displayed proximate each other; and   a cursor, displayed upon the enhanced radiological image, indicative of a location of the imaging probe while acquiring data for the intravascular image element presently displayed on the composite image, said cursor having a position that is based at least in part on third data derived from the radiopaque marker image data stored in the third memory portion.   
     
     
       41. The method of  claim 40 , wherein the calculated path is calculated using a first multiplication coefficient if the imaging probe is being pulled through the vessel and a second multiplication coefficient if the imaging probe is being pushed through the vessel. 
     
     
       42. The system of  claim 40 , wherein the imaging flexible elongate member is a catheter. 
     
     
       43. The system of  claim 40 , wherein the imaging flexible elongate member is a guidewire. 
     
     
       44. The system of  claim 40 , wherein the imaging probe includes an ultrasound transducer. 
     
     
       45. The system of  claim 40 , wherein the imaging probe includes a pressure sensor. 
     
     
       46. A system for providing an enhanced image of a vessel, the system comprising:
 a processing system in communication with a diagnostic probe and a display, the processing system configured to:
 receive angiogram image data of the vessel, wherein the angiogram image data is obtained with contrast flow; 
 receive fluoroscopic image data of the vessel and the diagnostic probe obtained while the diagnostic probe is positioned within and moved along a length of the vessel, the diagnostic probe including a radiopaque marker; 
 receive intravascular diagnostic data obtained by the diagnostic probe from within the vessel; 
 output an enhanced angiographic image of the vessel to the display, the enhanced angiographic image including:
 an angiogram of the vessel based on the received angiogram image data; and 
 a marker indicative of a position of an element of the diagnostic probe along the length of the vessel based on a location of the radiopaque marker in the received fluoroscopic image data, 
 wherein the marker is superimposed on the angiogram of the vessel based on the location of the radiopaque marker in the received fluoroscopic image data; and 
 
 output a visual representation of the intravascular diagnostic data to the display, the visual representation of the intravascular diagnostic data including the intravascular diagnostic data associated with the position of the element of the diagnostic probe along the length of the vessel.  
   
     
     
       47. The system of claim 46, wherein the fluoroscopic image data is obtained without contrast flow.  
     
     
       48. The system of claim 46, wherein the diagnostic probe is an intravascular imaging probe.  
     
     
       49. The system of claim 48, wherein the intravascular imaging probe is at least one of an intravascular ultrasound (IVUS) probe and an optical coherence tomography (OCT) probe.  
     
     
       50. The system of claim 48, wherein the visual representation of the intravascular diagnostic data is a cross-sectional image of the vessel.  
     
     
       51. The system of claim 46, wherein the diagnostic probe is a hemodynamic intravascular probe.  
     
     
       52. The system of claim 47, wherein the hemodynamic intravascular probe includes at least one of a pressure sensor and a flow sensor.  
     
     
       53. The system of claim 52, wherein the visual representation of the intravascular diagnostic data is a graph of a hemodynamic variable along the length of the vessel.  
     
     
       54. The system of claim 53, wherein the hemodynamic variable is a fractional flow reserve (FFR) value.  
     
     
       55. The system of claim 46, wherein the marker of the enhanced angiographic image is generated by superimposing the fluoroscopic image data onto the angiogram image data.  
     
     
       56. The system of claim 55, wherein superimposing the fluoroscopic image data onto the angiogram image data accounts for an angular orientation of the radiopaque marker.  
     
     
       57. The system of claim 56, wherein the angular orientation of the radiopaque marker is determined by identifying corners of a four-sided polygon of an image of the radiopaque marker in the fluoroscopic image data.  
     
     
       58. The system of claim 56, wherein the diagnostic probe includes at least two radiopaque markers.  
     
     
       59. The system of claim 58, wherein the radiopaque markers have different profiles such that an angular orientation of the diagnostic probe can be determined from an image of the radiopaque markers in the fluoroscopic image data.  
     
     
       60. The system of claim 56, wherein superimposing the fluoroscopic image data onto the angiogram image data further utilizes at least one of: one or more dimensions of the diagnostic probe, image field information for the angiogram image data, and image field information for the fluoroscopic image data.  
     
     
       61. The system of claim 46, wherein the marker operates as a slider control such that as the marker is moved the output visual representation of the intravascular diagnostic data is updated based on the location of the marker and the associated position of the element of the diagnostic probe along the length of the vessel.  
     
     
       62. The system of claim 46, further comprising the diagnostic probe.  
     
     
       63. The system of claim 62, wherein the diagnostic probe is at least one of a catheter or a guidewire.