Apparatus and method for tracking movement of a target

• US 20090039886A1
• Filed: 05/19/2008
• Published: 02/12/2009
• Est. Priority Date: 11/16/2005
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System), US Government As Represented By The Dept of Veterans Affairs
• Original Assignee: Briggs Macfarlane and Zaremba
• Inventors: White, Keith D.
• Granted Patent: US 7,977,942 B2
• Time in Patent Office: Days
• US Class Current: 324/318
• CPC Class Codes: G01R 33/28 Details of apparatus provided for in groups G01R33/44 - G01R33/64
• CPC Class Codes: G01R 33/4806 Functional imaging of brain activation
• CPC Class Codes: G01R 33/543 Control of the operation of the MR system, e.g. setting of acquisition parameters prior to or during MR data acquisition, dynamic shimming, use of one or more scout images for scan plane prescription G01R33/546 takes precedence
• CPC Class Codes: G01R 33/56509 due to motion, displacement or flow, e.g. gradient moment nulling G01R33/567 takes precedence
• CPC Class Codes: G01V 8/20 using multiple transmitters or receivers

Abstract

The present invention discloses an apparatus and method to track the movement of a target. One embodiment tracks the movement of the patient during medical imaging scanning using optical technology. Optical systems record the position and movement of the target and provide inputs to a processor. The processor is capable of performing mathematical analysis of the movement of the target to determine the positional shift of the patient. Weighted averages, phase correlation, Fourier-Mellin algorithms, and cross-correlation of data related to X-Y translation are used to calculate movement of the target subject. Feedback related to the movement is provided to the medical imaging scanning machine which allows for adjustments in focusing coils for real time tracking of the patient'"'"'s movements during the procedure. As a result, the medical image scanning procedure becomes more accurate as it is adjusted for the patient'"'"'s movements.

Claims

1. An apparatus for tracking the movement of a target, comprising:

(a) a light source,

(b) a target capable of reflecting structured light;

(c) an optical receiver capable of receiving structured light;

(d) a processor programmed to;

(1) accept a set of image inputs from the optical receiver; and

,

2) determine the movement of the target based upon the set of inputs from the optical receiver.

2. The apparatus of claim 1, wherein the processor is further programmed to determine the movement of the target through an algorithm selected from the group consisting of:

weighted average algorithm, phase correlation algorithm, and Fourier-Mellin algorithm.

3. The apparatus of claim 1, further comprising a medical imaging device programmed to receive the movement of the target and adjust a medical image based on the movement of the target.

4. The apparatus of claim 1, further comprising a spatial light modulator located between the light source and the target.

5. The apparatus of claim 1, wherein the light source is a laser.

6. The apparatus of claim 1, wherein the optical receiver is a CCD camera.

7. The apparatus of claim 3, wherein the medical imaging device is a MRI device.

8. The apparatus of claim 1, wherein the target is a sticker attached to a patient.

9. A system to track the movement of a target positioned in a MRI device comprising:

a structured light generator producing a structured light signal related to the target;

a receiver receiving the structured light signal and translating it into data related to the movement of the target; and

,

a feedback loop connected to the receiver and the MRI device, for supplying the data to the MRI device.

10. The system to track the movement of a target positioned in an MRI device of claim 9, further comprising:

a field adjustment means connected to the MRI device for adjusting the imaging capability of the MRI device in response to the movement of the target.

11. A method for tracking movement of a target, the method comprising:

producing light from a light source;

passing the light through a structured light generator;

projecting structured light onto the target;

reflecting structured light off the target;

passing the reflected light through an analyzer;

receiving reflected light from the analyzer into a detector array;

processing received reflected light to determine spatial coordinates of a first position of the target;

processing received reflected light to determine spatial coordinates of a second position of the target; and

,

tracking movement of the target.

12. The method for tracking movement of a target of claim 11, further comprising the step of selecting the structured light generator from the group consisting of a speckle pattern, a spatial filter, a slide, an array of light emitters, a liquid crystal display, or a MEMS device.

13. The method for tracking movement of a target of claim 11, wherein the step of producing light includes producing at least two frequencies of light.

14. The method for tracking movement of a target of claim 11, further comprising affixing a reflective tag to a patient.

15. The method for tracking movement of a target of claim 11, wherein the step of receiving reflected light includes receiving at least two frequencies of light.

16. The method for tracking movement of a target of claim 11, further comprising the step of selecting the analyzer from the group consisting of a filter or a polarizer.

17. The method for tracking movement of a target of claim 11, wherein the step of receiving reflected light includes receiving reflected light from the analyzer in a CCD camera.

18. The method for tracking movement of a target of claim 11, further comprising:

transmitting tracked movement to a medical imaging scanning device; and

adjusting the medical imaging scanning device in response to the determined movement.

19. The method for tracking movement of a target of claim 18, further comprising transmitting tracked movement to an MRI.