Registration of ultrasound to fluoroscopy for real time optimization of radiation implant procedures

• US 20050171428A1
• Filed: 07/21/2004
• Published: 08/04/2005
• Est. Priority Date: 07/21/2003
• Status: Abandoned Application

• Current Assignee: Johns Hopkins University
• Original Assignee: Johns Hopkins University
• Inventors: Burdette, E. Clif, Fichtinger, Gabor, Mustufa, Tabish, Wyrobek, Keenan
• Application Number:
  US10/895,398
• Publication Number:
  US 20050171428A1
• Time in Patent Office: Days
• US Class Current: 600/426
• CPC Class Codes: A61B 2090/392 Radioactive markers
• CPC Class Codes: A61B 2090/3925 ultrasonic
• CPC Class Codes: A61B 2090/3937 Visible markers
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image
• CPC Class Codes: A61B 6/4417 related to combined acquisition of different diagnostic modalities
• CPC Class Codes: A61B 6/504 for diagnosis of blood vessels, e.g. by angiography
• CPC Class Codes: A61B 6/5247 combining images from an ionising-radiation diagnostic technique and a non-ionising radiation diagnostic technique, e.g. X-ray and ultrasound
• CPC Class Codes: A61B 6/583 using calibration phantoms
• 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 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61N 5/1014 Intracavitary radiation therapy

Abstract

Transrectal ultrasound guided transperineal low dose-rate brachytherapy has been emerged as one of the definitive treatments of low-risk prostate cancer. Ultrasound has been an excellent tool in guiding the implant needles with respect to prostate anatomy, yet it cannot show reliably the location of radioactive seeds after they are released in the prostate. Intraoperative C-arm fluoroscopy can show the implanted seeds, but it cannot detect prostate anatomy. Intra-operative fusion of these two complementary modalities offers significant clinical benefit by allowing for real-time optimization of the brachytherapy implant as the procedure progresses in the operating room. Disclosed is a system and method for mitigating this problem and providing registration of seeds seen by fluoroscopy with live prostate anatomy visualized by transrectal ultrasound.

Claims

1. A system for registering ultrasound and fluoroscopy data comprising:

a fluoroscope;

a sheath having fiducial marks disposed on a portion of its outer surface;

an ultrasound probe insertable into the sheath;

a computer; and

a computer readable medium encoded with a program for registering a first set of data acquired by the ultrasound probe with a second set of data acquired by the fluoroscope.

2. The system of claim 1, wherein the ultrasonic probe includes a stepper.

3. The system of claim 1, wherein the fiducial marks comprise Tantalum.

4. The system of claim 1, wherein the fiducial marks comprise a wire including a thickness of substantially 1 mm.

5. The system of claim 1, wherein the fluoroscope is a C-arm fluoroscope comprising an image intensifier.

6. The system of claim 1, wherein the sheath comprises a thin plastic.

7. The system of claim 1, further comprising a gel material disposed between the sheath and the ultrasound probe.

8. A method for registering ultrasound to fluoroscopy comprising the steps of:

calibrating a fluoroscope;

acquiring ultrasound data using an ultrasound probe;

acquiring fluoroscopy data from the fluoroscope;

registering the ultrasound data to the fluoroscopy data to create a set of registered data;

identifying at least one radiation seed in the registered data; and

computing a radiation dose corresponding to the at least one radiation seed.

9. The method of claim 8, wherein the step of calibrating the fluoroscope comprises the steps of:

attaching a dewarping plate having a bead pattern to the fluoroscope;

acquiring calibration data from the fluoroscope;

correlating the calibration data to the bead pattern;

determining a transformation corresponding to the correlating; and

aligning the calibration data to the bead pattern.

10. The method of claim 8, wherein the step of acquiring fluoroscopy data comprises the steps of:

acquiring an image from the fluoroscope;

dewarping the image;

reducing noise in the image;

normalizing the image;

removing background from the image;

thresholding the image; and

pre-labeling the image.