Coronary artery imaging system using gated tomosynthesis

• US 4,662,379 A
• Filed: 08/27/1986
• Issued: 05/05/1987
• Est. Priority Date: 12/20/1984
• Status: Expired due to Fees

• Current Assignee: Stanford University
• Original Assignee: Stanford University
• Inventors: Macovski, Albert
• Primary Examiner(s): Howell, Kyle L.
• Assistant Examiner(s): JAWORSKI, FRANCIS J
• Application Number:
  US06/902,086
• Time in Patent Office: 251 Days
• Field of Search: 378/9, 378/11, 378/15, 378/21-22
• US Class Current: 600/428
• CPC Class Codes: A61B 6/025 Tomosynthesis
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/405 Source units specially adapted to modify characteristics of the beam during the data acquisition process A61B6/4021, A61B6/4035 take precedence
• CPC Class Codes: A61B 6/481 involving the use of contrast agents
• CPC Class Codes: A61B 6/482 involving multiple energy imaging
• CPC Class Codes: A61B 6/504 for diagnosis of blood vessels, e.g. by angiography
• CPC Class Codes: A61B 6/541 involving acquisition triggered by a physiological signal
• CPC Class Codes: H04N 5/3205 using subtraction imaging techniques
• CPC Class Codes: H05G 1/26 Measuring, controlling or protecting measuring X-ray radiation G01T
• CPC Class Codes: H05G 1/60 Circuit arrangements for obtaining a series of X-ray photographs or for X-ray cinematography

Abstract

A method of imaging a blood vessel such as a coronary artery includes the steps of a dual energy providing radiation source and a radiation detector on opposing sides of a target area and at a plurality of angular positions through the target area. The radiation source is gated at the plurality of positions after administering a contrast agent intravenously to obtain a first plurality of detector signals indicative of a first plurality of views through said target area. The first plurality of detector signals are then tomosynthesisly combined to provide a planar image through the target area. Preferably, the gating of the radiation source after administering a contrast agent includes gating based on a selected time using an electrocardiogram, and the gating is at at least two energy levels to obtain detector signals at each energy level indicative of said plurality of views. Soft tissue is eliminated by combining signals at the least two image levels.

Claims

1. A method of imaging a blood vessel such as a coronary artery comprising the steps of

providing radiation source means and radiation detector means on opposing sides of a target area and at a plurality of administering a contrast agent intravenously,

gating said radiation source means based on a selected time using an electrocardiogram to obtain a first plurality of detector signals indicative of a first plurality of views through said target area and,

tomosynthesisly combining said first plurality of detector signals to provide a planar image through said target area, said planar image being generally perpendicular to the path of radiation through said target area.

2. The method as defined by claim 1 wherein said step of gating said radiation source includes gating said radiation source at at least two energy levels to obtain detector signals at each energy level indicative of said plurality of views, and further including the step of eliminating soft tissue by combining signals at said at least two image levels.

3. The method as defined by claim 2 and further including the step of gating said radiation source means at said plurality of positions prior to administering a contrast agent intravenously to obtain a second plurality of detector signals indicative of a second plurality of views through said target area, said step including gating said radiation source at said at least two energy levels to obtain detector signals at each energy level indicative of said plurality of views, said first plurality of detector signals and said plurality of detector signals being combined by hybrid subtraction.

4. The method as defined by claim 1 and further including the step of gating said radiation source means at said plurality of positions prior to administering said contrast agent intravenously to obtain a second plurality of detector signals indicative of a second plurality of views through said target area, said step including gating said radiation source at said at least two energy levels to obtain detector signals at each energy level indicative of said plurality of views, said first plurality of detector signals and said plurality of detector signals being combined by hybrid subtraction.

5. Apparatus for imaging a blood vessel such as a coronary artery comprising

radiation source means and radiation detector means positioned on opposing sides of a target area and at a plurality of angular positions through the target area,

means for gating said radiation source means at said plurality of positions including means responsive to an electrocardiogram for gating said source means at a selected time during a heart-beat for obtaining a first pluralitiy of detector signals indicative of a first plurality of views through said target area, and

tomosynthesis means for combining said first plurality of detector signals to provide a planar image through said target area, said planar image being generally perpendicular to the path of radiation through said target area.