Intraluminal and extraluminal image registration

1 . A system for registering positions of a temporal sequence of intraluminal sensing device data generated by an intraluminal sensing device to positions along a guidewire in a temporal sequence of extraluminal image frames including the intraluminal sensing device and the guidewire,

wherein the intraluminal sensing device comprises a plurality of radiopaque markers,

wherein the system comprises one or more processors configured to:

identify the guidewire in an extraluminal image frame;

identify positions of the plurality of radiopaque markers along the guidewire by sampling a first set of image intensity values in the extraluminal image frame with a first spatial resolution;

compute an estimated separation between at least one pair of the plurality of radiopaque markers based on the identified positions of the plurality of radiopaque markers;

sample the first set of image intensity values in the extraluminal image frame with a second spatial resolution, to determine a matching between the first set of image intensity values and a second set of image intensity values known to represent a portion of the intraluminal sensing device, wherein the second spatial resolution is determined based on the estimated separation and a known separation between the at least one pair,

determine a position of a sensing portion of the intraluminal sensing device along the guidewire, based on the matching; and

map a position of intraluminal sensing device data generated contemporaneously with the extraluminal image frame to the determined position.

2 . The system of claim 1 , wherein the second set of image intensity values is known to represent the sensing portion of the intraluminal sensing device.

3 . The system of claim 1 , wherein the temporal sequence of intraluminal sensing device data comprises a temporal sequence of intraluminal image frames.

4 . The system of claim 3 , wherein the intraluminal ultrasound image frames comprise intravascular ultrasound image frames or endobronchial ultrasound image frames.

5 . The system of claim 3 , wherein the temporal sequence of extraluminal image frames comprise radiographic image frames.

6 . A computer-implemented method of registering positions of a temporal sequence of intraluminal sensing device data generated by an intraluminal sensing device to positions along a guidewire in a temporal sequence of extraluminal image frames including the intraluminal sensing device and the guidewire,

wherein the intraluminal sensing device comprises a plurality of radiopaque markers,

wherein the method comprises:

identifying the guidewire in an extraluminal image frame;

identifying positions of the plurality of radiopaque markers along the guidewire by sampling a first set of image intensity values in the extraluminal image frame with a first spatial resolution;

computing an estimated separation between at least one pair of the plurality of radiopaque markers based on the identified positions of the plurality of radiopaque markers;

sampling the first set of image intensity values in the extraluminal image frame with a second spatial resolution, to determine a matching between the first set of image intensity values and a second set of image intensity values known to represent a portion of the intraluminal sensing device, wherein the second spatial resolution is determined based on the estimated separation and a known separation between the at least one pair,

determining a position of a sensing portion of the intraluminal sensing device along the guidewire, based on the matching; and

mapping a position of intraluminal sensing device data generated contemporaneously with the extraluminal image frame to the determined position along the guidewire.

7 . The computer-implemented method of claim 6 ,

wherein the second set of image intensity values is known to represent the sensing portion of the intraluminal sensing device,

wherein the intraluminal sensing device comprises an intravascular imaging device or an endobronchial imaging device,

wherein the temporal sequence of intraluminal sensing device data comprises a temporal sequence of intraluminal image frames provided by the intravascular imaging device or the endobronchial imaging device,

wherein the temporal sequence of extraluminal image frames comprise radiographic image frames.

8 . The computer-implemented method according to claim 7 ,

wherein the intravascular imaging device comprises an intravascular ultrasound (IVUS) imaging device,

wherein the radiographic image frames comprise X-ray image frames obtained from an X-ray imaging device and the temporal sequence of intraluminal image frames comprise IVUS image frames obtained from the IVUS imaging device.

9 . The computer-implemented method according to claim 6 ,

wherein the matching comprises:

sampling the first set of image intensity values within a window extending transversally with respect to the guidewire to provide a composite value for the window, at each position; and

comparing the composite values determined at the positions along the guidewire, with the second set of image intensity values, and

wherein the second set of image intensity values comprises an expected profile of the composite values along the guidewire.

10 . The computer-implemented method according to claim 8 ,

wherein the second set of image intensity values is known to represent an imaging portion of the IVUS imaging device,

wherein determining the position of the sensing portion of the intraluminal sensing device comprises determining a position of the imaging portion of the IVUS imaging device.

11 . The computer-implemented method according to claim 6 ,

wherein the radiopaque markers are coupled to the intraluminal sensing device and are distributed axially along the guidewire.

12 . The computer-implemented method according to claim 6 , comprising:

generating a template pattern representing the sensing portion of the intraluminal sensing device by averaging the first set of image intensity values surrounding the determined position; and

repeating determining the position of the sensing portion of the intraluminal sensing device along the guidewire for the temporal sequence of extraluminal image frames, using the template pattern, to provide an adjusted position of the sensing portion of the intraluminal sensing device along the guidewire in each extraluminal image frame.

13 . The computer-implemented method according to claim 6 ,

wherein the second set of image intensity values comprises an X-ray attenuation pattern of the plurality of radiopaque markers extending along an axial direction and/or a radial direction with respect to the guidewire.

14 . The computer-implemented method according to claim 6 ,

wherein the intraluminal sensing device comprises a catheter having a shaft,

wherein the plurality of radiopaque markers are coupled to the catheter and distributed axially along the shaft of the catheter, and

wherein the method comprises:

identifying the plurality of radiopaque markers in the extraluminal image frame; and

determining a scale factor based on the estimated separation and the known separation.