Device for guiding a medical imaging probe and method for guiding such a probe

• US 9,538,983 B2
• Filed: 06/03/2013
• Issued: 01/10/2017
• Est. Priority Date: 06/01/2012
• Status: Active Grant

• Current Assignee: Koelis Co.
• Original Assignee: Koelis Co.
• Inventors: Baumann, Michael, Leroy, Antoine
• Primary Examiner(s): Lamprecht, Joel
• Application Number:
  US14/397,407
• Publication Number:
  US 20150119715A1
• Time in Patent Office: 1,317 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 17/3403 Needle locating or guiding means guides for suture needles A61B17/0482; guiding or tracking by nuclear magnetic resonance G01R33/285
• CPC Class Codes: A61B 2017/00274 Prostate operation, e.g. prostatectomy, turp, bhp treatment
• CPC Class Codes: A61B 2017/3405 using mechanical guide means
• CPC Class Codes: A61B 2017/3413 guided by ultrasound
• CPC Class Codes: A61B 2034/2048 using an accelerometer or inertia sensor
• CPC Class Codes: A61B 2090/3784 both receiver and transmitter being in the instrument or receiver being also transmitter
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 8/0841 for locating instruments
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/4254 using sensors mounted on the probe
• CPC Class Codes: A61B 8/4461 Features of the scanning mechanism, e.g. for moving the transducer within the housing of the probe
• CPC Class Codes: A61B 8/4488 the transducer being a phased array
• CPC Class Codes: A61B 8/5215 involving processing of medical diagnostic data

Abstract

A device for guiding a medical imaging probe in order to move the probe close to an anatomical space, the probe having a mechanism for acquiring images of the anatomical space, and the device having at least one sensor mounted to the probe. The device includes a processing mechanism for deducing a rotation of the probe in the space from the signals generated by the sensor and for estimating a plurality of plausible positions of the probe relative to the anatomical space by deducing the rotation of the probe in the space. The processing mechanism is arranged such as to determine the position of the probe relative to the anatomical space from the plausible positions. Also disclosed is a method for guiding the probe.

Claims

1. A device for guiding a medical imaging probe in order to bring said probe in proximity to an anatomical volume, the probe comprising means for acquiring images of the anatomical volume, the device comprising at least one sensor fixed to the probe and capable of generating signals representing at least one rotation of the probe in space, the device comprises a control unit which is connected to the probe and comprises means for processing the images in order to localize the probe relative to the anatomical volume, the processing means being capable of deducing a rotation of the probe in space on the basis of the signals generated by the sensor, the processing means comprising means for estimating a plurality of plausible positions of the probe relative to the anatomical volume on the basis of at least the deduction of the rotation of the probe in space, the processing means being arranged in order to determine the position of the probe relative to the anatomical volume on the basis of:

a reference image of the anatomical volume acquired by the means for acquiring images of the anatomical volume during an initialization phase,

at least one image acquired by the image acquisition means during a phase of motion following the initialization phase, and

the plausible positions.

2. The device as claimed in claim 1, wherein the sensor is capable of generating only signals representing the rotation of the probe in space.

3. The device as claimed in claim 1, wherein the processing means are arranged in order to determine only an angular position of the probe relative to the anatomical volume on the basis of the signals generated by the sensor, and the estimation means are arranged in order to determine a plurality of plausible positions of the probe on the basis of said angular position.

4. The device as claimed in claim 1, wherein the image acquisition means comprise a linear ultrasound array, and a motor which is arranged so as to drive the linear ultrasound array in rotation about a rotation axis during use.

5. The device as claimed in claim 4, wherein the control unit is arranged so as to control the motor and the linear ultrasound array so that the motor moves the linear ultrasound array in a restricted rotation range, typically of 20 degrees, about the rotation axis during use.

6. The device as claimed in claim 4, wherein the control unit is arranged so as to control the motor and the linear ultrasound array so that during use, after a first series of image acquisitions, the motor brings the linear ultrasound array into an initial position for a second series of image acquisitions, said initial position being determined at least on the basis of the images of the first series.

7. A method for guiding a medical probe for medical imaging in order to bring the probe in proximity to an anatomical volume;

the method comprising;

providing a probe that acquires images of the anatomical volume, wherein fixed to the probe is at least one sensor capable of generating signals representing at least one rotation of the probe in space and performing the following steps;

acquiring a reference image of the anatomical volume during an initialization phase and during a phase of motion following the initialization phase;

processing the signals generated by the sensor in order to deduce therefrom at least one rotation of the probe in space;

estimating a plurality of plausible positions of the probe relative to the anatomical volume on the basis of at least the deduction of the rotation of the probe in space;

processing the images in order to localize the probe relative to the anatomical volume by determining the position of the probe relative to the anatomical volume on the basis of the reference image of the anatomical volume, of at least one image acquired by the probe, and of the plausible positions which have been determined.

8. The method as claimed in claim 7, wherein the step of estimating a plurality of plausible positions is carried out by a statistical or cinematic model.

9. The method as claimed in claim 7, wherein the step of estimating a plurality of plausible positions is carried out on the basis of the deduction of only the rotation of the probe in space.

10. The method as claimed in claim 7, furthermore comprising the step of selecting only certain plausible positions of the probe relative to the anatomical volume in order to initialize the step of processing the images, in order to localize the probe relative to the anatomical volume by determining the position of the probe relative to the anatomical volume.

11. The method as claimed in claim 7, furthermore comprising the step of validating the position of the probe which has been determined relative to the anatomical volume.

12. The method as claimed in claim 7, comprising the successive steps of:

acquiring at least one reference image of the anatomical volume and determining at least one angular position of the probe in space, associated with the reference image, referred to as a reference angular position;

acquiring at least a first image of the anatomical volume and determining at least a first angular position of the probe in space, associated with said image by processing the signals generated by the sensor in order to deduce therefrom the rotation of the probe in space;

on the basis of the reference image, the reference angular position, the first image and the first angular position, determining a finite number of positions of the probe relative to the anatomical volume by a statistical or cinematic model, so as to estimate a plurality of plausible positions of the probe relative to the anatomical volume;

for each plausible position, calculating a similarity parameter between the image of the anatomical volume and a transformation of the reference image on the basis of said plausible position;

with the aid of the similarity parameters calculated in the preceding step, selecting among the plausible positions closest to a real position of the probe relative to the anatomical volume;

refining the determination of each position of the probe relative to the anatomical volume by local optimization on each of the similarity parameters associated with the positions;

among all the positions thus refined, selecting the position whose associated similarity parameter is maximum after the local optimization step, said position being the position determined for the probe relative to the anatomical volume.

13. The method as claimed in claim 12, wherein the similarity parameter is calculated on the basis of a cross-correlation over the gray levels between the image of the anatomical volume and the transformation of the reference image.

14. A medical device, comprising:

an imaging probe configured to acquire images of an anatomical volume;

a device configured to guide the imaging probe in order to bring the probe in proximity to the anatomical volume;

the device comprising at least one sensor fixed to the imaging probe and that generates a signal representing at least one rotation of the probe in space;

the device comprises a control unit connected to the probe and a processor in which the images are processed in order to localize the probe relative to the anatomical volume, the processor configured to deduce a rotation of the probe in space on the basis of the signals generated by the sensor and configured to estimate a plurality of plausible positions of the probe relative to the anatomical volume on the basis of at least the deduction of the rotation of the probe in space, and the processor arranged to determine the position of the probe relative to the anatomical volume on the basis of a reference image of the anatomical volume acquired by the imaging probe during an initialization phase, of at least one image acquired by the imaging probe during a phase of motion following the initialization phase, and the plausible positions.