Screen-based interactive image-plane prescription for MRI

• US 5,512,826 A
• Filed: 06/02/1995
• Issued: 04/30/1996
• Est. Priority Date: 06/02/1995
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Darrow, Robert D., Hardy, Christopher J.
• Primary Examiner(s): TOKAR, MICHAEL J
• Application Number:
  US08/458,601
• Time in Patent Office: 333 Days
• Field of Search: 128/653.1, 128/653.2, 128/653.3, 324/300, 324/307, 324/309, 324/310, 324/311, 324/312, 324/313, 324/314, 324/318, 324/322
• US Class Current: 324/309
• CPC Class Codes: G01R 33/54 Signal processing systems, e.g. using pulse sequences ; Generation or control of pulse sequences; Operator console
• 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 33/546 Interface between the MR system and the user, e.g. for controlling the operation of the MR system or for the design of pulse sequences

Abstract

An MR image of a subject is displayed on a display device. Scan-control icons are displayed over this image. An operator interacts with an interface device to select imaging plane parameters during imaging. This is performed by selecting one of the icons with a pointing device, and dragging. Interface device then provides a display which indicates the motion of the imaging plane as well as the extent of the motion. Once selected, the location and orientation information transformed to global coordinates and is provided to a pulse sequencer of a magnetic resonance (MR) imaging system. The pulse sequencer controls an RF transmitter and gradient amplifiers to cause an MR image of the subject at an imaging plane to be acquired. This allows fast, accurate imaging plane selection, which may be selected by an operator who is searching for structures within the subject, or who is simultaneously performing a medical procedure on the subject.

Claims

1. A method of producing magnetic resonance (MR) images of a subject in an MR imaging device in an interactive fashion, comprising the steps of:

a) acquiring a current MR image of said subject at an imaging plane centered at (x,y,z) and oriented at angles (θ

,φ

,κ

) with respect to I_x,I_y,I_z axes of a global coordinate system fixed with respect to the MR Imaging device;

b) displaying the current image on a monitor screen;

c) enabling imaging plane prescription by selecting an enable button displayed on the monitor;

d) displaying a x,y translate icon, a z translate icon, a spin icon and a tilt icon

e) translating a center of a proposed imaging plane by a translation offset Δ

z proportional to γ

, when the z translate icon is selected and dragging it a distance γ

,

f) translating the center of the proposed imaging plane by a translation offset Δ

x,Δ

y proportional to α

,β

, when the x,y translate icon is selected and dragging it a distance α

,β

in the x, y directions, respectively;

g) rotating about the Z axis through the center of the imaging plane by a rotation offset Δ

κ

proportional to γ

, when the spin icon is selected and dragging an angle γ

,

h) rotating the proposed imaging plane by rotation offsets Δ

θ

,Δ

φ

about the X and Y axes, respectively, when the tilt icon is selected and dragged through angular distances

i) transforming the offsets to transformed coordinates relative to the global coordinate system;

j) passing the transformed coordinates to said MR imaging device;

k) acquiring a new MR image with the transformed coordinates; and

l) displaying the newly acquired MR image as the current image.

2. The method of producing MR images of claim 1 wherein steps "d" - "l" are repeated a plurality of repetitions to allow interactive imaging of structures within said subject from a desired perspective.

3. The method of producing MR images of claim 1 further comprising, before the step of acquiring a new MR image, the step of displaying visual feedback on the monitor indicating the proposed imaging plane offsets relative to the current imaging plane.

4. The method of producing MR images of claim 3 wherein the step of displaying visual feedback comprises the steps:

a) displaying the x,y translation icon at a monitor screen location indicating the center of the proposed imaging plane at the monitor screen locations determined by the translation offsets (Δ

x,Δ

y) when the x,y translation icon is selected and dragged;

b) displaying the z translation icon at a monitor screen location and a size simulating depth perspective, indicative of the proposed imaging plane depth Δ

z, when the z translation icon is selected and dragged; and

c) displaying the z rotation icon and an outline of the proposed imaging-plane at a monitor screen location to indicate a rotation offset Δ

κ

of the proposed imaging plane relative to is the current imaging plane when the z rotation icon is selected and dragged; and

d) displaying the outline of the proposed imaging plane oriented at rotation offsets (θ

,φ

) to indicate the orientation of the proposed imaging plane relative to the current imaging plane when the tilt icon is selected and dragged.

5. An interactive magnetic resonance (MR) imaging system comprising:

a) an MR imaging device for acquiring MR images of a subject at an imaging plane defined in global coordinate system fixed with respect to the imaging device;

b) transformation means coupled to the MR imaging device, for converting proposed imaging plane offsets defined with respect to a current imaging plane to global coordinates;

c) a monitor for displaying images and screen buttons at predefined screen locations provided to it;

d) a pointing device functionally coupled to the transformation means, for interacting with an operator for selecting screen locations and dragging icons over a plurality of screen locations;

e) an interface means coupled to the pointing device, the monitor, the transformation means, for receiving the selected screen locations, for calculating icons pertaining to the selected screen locations, for determining the screen locations over which the selected icon was dragged, for adjusting proposed imaging plane translation offsets (Δ

x,Δ

y),Δ

z, proposed imaging plane rotation offsets (Δ

θ

,Δ

φ

), Δ

κ

, and for providing the proposed imaging plane offsets to the transformation means causing the MR imaging device to acquire a new image with the proposed imaging plane offsets.

6. The interactive magnetic resonance (MR) imaging system of claim 5 wherein the interface means further comprises:

a) a sound generator for receiving the rotation and translation offsets, and for producing a unique sound signal for each offset actively being changed; and

b) a speaker device coupled to the sound generator for convening the sound signal to an audible sound.