SYSTEM AND METHOD FOR NON-INVASIVE PATIENT-IMAGE REGISTRATION

• US 20150049174A1
• Filed: 11/12/2013
• Published: 02/19/2015
• Est. Priority Date: 08/13/2013
• Status: Active Grant

• Current Assignee: Korea Advanced Institute of Science and Technology
• Original Assignee: Korea Advanced Institute of Science and Technology
• Inventors: PARK, Se Hyung, LEE, Deukhee, LIM, Sunghwan
• Granted Patent: US 9,554,117 B2
• Time in Patent Office: Days
• US Class Current: 348/50
• CPC Class Codes: A61B 2034/2055 Optical tracking systems
• CPC Class Codes: A61B 2090/364 Correlation of different images or relation of image positions in respect to the body
• CPC Class Codes: A61B 6/504 for diagnosis of blood vessels, e.g. by angiography
• CPC Class Codes: A61B 8/0891 for diagnosis of blood vessels
• CPC Class Codes: A61B 90/361 Image-producing devices, e.g. surgical cameras
• CPC Class Codes: G06T 2207/10012 Stereo images
• CPC Class Codes: G06T 2207/10048 Infrared image
• CPC Class Codes: G06T 2207/10072 Tomographic images
• CPC Class Codes: G06T 2207/20044 Skeletonization; Medial axis transform
• CPC Class Codes: G06T 2207/30101 Blood vessel; Artery; Vein; Vascular
• CPC Class Codes: G06T 2207/30172 Centreline of tubular or elongated structure
• CPC Class Codes: G06T 7/33 using feature-based methods
• CPC Class Codes: H04N 13/221 using the relative movement between cameras and objects

Abstract

Disclosed is a system for non-invasive registration between a patient and a three-dimensional (3D) medical image, the system comprising: a near infrared 3D camera 110 which extracts a 3D blood vessel image I2 of a patient'"'"'s registration target area during surgical operation; a camera position tracer 120 which traces a position of the near infrared 3D camera 110 and calculates a real world coordinate system of the 3D blood vessel image I2; a controller 130 which extracts a first blood vessel pattern from a 3D medical image I1 of the registration target area, extracts a second blood vessel pattern from the 3D blood vessel image I2, and performs position registration between the patient and the 3D medical image I1 through the extracted first and second blood vessel patterns; and a display 140 which displays a registration result calculated by the controller 130.

Claims

1. A system for non-invasive registration between a patient and a three-dimensional (3D) medical image, the system comprising:

a near infrared 3D camera 110 which extracts a 3D blood vessel image I2 of a patient'"'"'s registration target area at a surgical operation;

a camera position tracer 120 which traces a position of the near infrared 3D camera 110 and calculates a real world coordinate system of the 3D blood vessel image I2;

a controller 130 which extracts a first blood vessel pattern from a 3D medical image I1 of the registration target area, extracts a second blood vessel pattern from the 3D blood vessel image I2, and performs position registration between the patient and the 3D medical image I1 through the extracted first and second blood vessel patterns; and

a display 140 which displays a registration result calculated by the controller 130.

2. The system according to claim 1, wherein the controller 130 comprises:

a 3D medical image database (DB) 131 which stores a 3D medical image I1 obtained by taking the registration target area before a surgical operation;

a blood vessel model generator 132 which reconstitutes the blood vessel model by having a blood vessel image separated from the 3D medical image I1;

a first feature point extractor 133 which extracts a branch point, from which a blood vessel is branched by detecting a skeleton line SL of the blood vessel model, and selects each extracted branch point as a feature point of the first blood vessel pattern;

a 3D blood vessel image detector 134 which extracts a 3D blood vessel image I2 by separating a blood vessel image from a near infrared 3D image taken by the near infrared 3D camera 110, and a the second feature point extractor 135 which extracts a branch point of a patient'"'"'s blood vessel at a surgical operation through the extracted 3D blood vessel image I2 and a real world coordinate system of the 3D blood vessel image I2 measured by the camera position tracer 120, and selects each extracted branch point as a feature point of the second blood vessel pattern; and

a registrator 136 which performs registration by optimally matching a first feature point group P1 comprising of a plurality of first feature points, and a second feature point group P2 comprising of a plurality of second feature points.

3. The system according to claim 2, wherein

the first feature point extractor 133 stores 3D coordinates of a feature point of a first blood vessel pattern selected with respect to a medical image coordinate system,

the near infrared 3D camera 110 takes blood vessel images seen by near infrared light through a patient'"'"'s registration target area to obtain two 3D blood vessel images I2 spaced apart at a predetermined distance to have parallax, and

the second feature point extractor 135 selects a second feature point represented by 3D coordinates with respect to a 3D camera coordinate system, using parallax of a pair of corresponding branch points respectively calculated from two 3D blood vessel images I2 of the near infrared 3D camera 110.

4. The system according to claim 3, wherein

the camera position tracer 120 measures six degrees of freedom in position of the near infrared 3D camera 110, which includes three rotation positions and three translation positions, and calculates a coordinate transformation matrix M from the position tracer coordinate system to the 3D camera coordinate system by tracing the position of the near infrared 3D camera 110 in real time,

the second feature point extractor 135 transforms and saves the second feature point in the 3D camera coordinate system into that in a position tracer coordinate system by the coordinate transformation matrix M, and

the registrator 136, non-invasive registration system between patient and 3D medical image, calculates a position relationship T of a position tracer coordinate system with respect to a medical image coordinate system in a state that a second feature point group P2 in the position tracer coordinate system is rotated and translated to be optimally matched with the first feature point group P1.

5. The system according to claim 4, wherein the camera position tracer 120 comprises a mechanical position tracing device 120a which is fastened to an end of an articulated link and measures six degrees of freedom in position of the near infrared 3D camera 110 by sensing a physical displacement due to link movement of each join.

6. The system according to claim 4, wherein the camera position tracer 120 comprises an optical position tracing device 120b which uses a 3D camera taking fiducial markers 121 mounted to the near infrared 3D camera 110 to calculate a 3D position vector and a 3D direction vector of the fiducial marker 121 and measure six degrees of freedom in position of the near infrared 3D camera 110.

7. The system according to claim 2, wherein the first feature point extractor 133 extracts a border line BL representing an outline of a blood vessel from the blood vessel model, and extracts a center line, which is extracted from the extracted border line BL along the blood vessel, as a skeleton line SL;

8. A method of non-invasive registration between a patient and a three-dimensional (3D) medical image, the method comprising:

extracting a 3D blood vessel image I2 by taking a blood vessel image seen by having near infrared light pass through a registration target area with a near infrared 3D camera 110 (S210);

tracing a camera position by tracing a position of the near infrared 3D camera 110 in real time with the camera position tracer 120 and calculating a real world coordinate system of the 3D blood vessel image I2 (S220);

extracting a blood vessel pattern with a controller 130 by extracting a first blood vessel pattern from a 3D medical image I1 of the registration target area and extracting a second blood vessel pattern from the 3D blood vessel image I2 (S230);

image registration by performing position registration between a patient and the 3D medical image I1 through the extracted first and second blood vessel patterns (S240); and

displaying a registration result by displaying the registration result calculated by the controller 130 on a screen (S250).