X-ray CT apparatus and X-ray radiographic method

• US 7,881,423 B2
• Filed: 08/28/2006
• Issued: 02/01/2011
• Est. Priority Date: 08/31/2005
• Status: Expired due to Fees

• Current Assignee: Toshiba Medical Systems Corporation (Canon Inc.)
• Original Assignee: Toshiba Medical Systems Corporation (Canon Inc.), Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Tsuyuki, Masaharu, Tanaka, Toyoaki
• Primary Examiner(s): Glick; Edward J
• Assistant Examiner(s): Taningco; Alexander H
• Application Number:
  US11/467,811
• Publication Number:
  US 20070053478A1
• Time in Patent Office: 1,618 Days
• Field of Search: 378 4- 20, 378/901, 378/64, 378/65
• US Class Current: 378/4
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/5235 combining images from the same or different ionising radiation imaging techniques, e.g. PET and CT

Abstract

An X-ray CT apparatus is adapted for switchover between a CT mode to obtain a tomographic image of a subject and a transmission mode to obtain a transmission image of the subject, depending upon projection data acquired in an imager system thereof. The apparatus includes an image-data storage device that stores image data of the subject in a three-dimensional region, a three-dimensional image processor that performs a three-dimensional image processing on the image data and generates three-dimensional image data, for display, corresponding to a line-of-sight direction inputted from an input device, and a transmission-image generator that generates the transmission image as to the image-taking direction, from data acquired in the imager system aligned by the CPU.

Claims

1. An X-ray CT apparatus comprising:

an imager system configured to include a table-top and gantry which has at least an X-ray tube and a multi-slice detector;

an input device configured to input a line-of-sight direction;

a mode setter configured to set a mode in a CT mode;

a tomographic image generator configured to perform a tomographic imaging of a subject in which X-rays forming a cone beam are irradiated from the X-ray tube to the multi-slice detector, and to generate tomographic images based upon the tomographic imaging;

an image data storage device configured to store image data based upon the tomographic images;

a three-dimensional image processor configured to perform three-dimensional image processing on the image data and to generate a three-dimensional image, for display, corresponding to an input line-of-sight direction;

a mode switcher configured to switch the mode only between a transmission mode and the CT mode;

a drive controller configured to control an alignment of an imager system depending upon an image-taking direction corresponding to the line-of-sight direction;

a transmission image generator configured to perform a transmission imaging of the subject in which the X-rays are irradiated from the X-ray tube aligned by the drive controller to the multi-slice detector aligned by the drive controller, and to generate a transmission image, based upon the transmission imaging, in the image-taking direction corresponding to the line-of-sight direction of the displayed three-dimensional image generated by the CT mode; and

a transmission image displayer configured to display the transmission image in substantially real-time.

2. The X-ray CT apparatus according to claim 1, further comprising:

an input device that inputs a predetermined portion of the three-dimensional image; and

a line-of-sight direction operator that operates a line-of-sight direction to display the predetermined portion with magnification, thereby inputting the line-of-sight direction to the drive control.

3. The X-ray CT apparatus according to claim 1, further comprising:

a display control that causes display of, as a three-dimensional image, three-dimensional image data for display in the image-taking direction; and

a monitor that displays the three-dimensional image.

4. The X-ray CT apparatus according to claim 1, further comprising:

a display control that causes display of the transmission image; and

a monitor that displays the transmission image.

5. The X-ray CT apparatus according to claim 1, wherein the multi-slice detector includes a plurality of arrays each of which has a plurality of X-ray detecting elements matched to a spread of the X-ray cone beam.

6. An X-ray CT apparatus comprising:

an imager system configured to include a table-top and a gantry which has at least an X-ray tube and a multi-slice detector;

an input device configured to input a line-of-sight direction;

a mode setter configured to set a mode in CT mode;

a positioning device configured to input a tilt angle of the gantry and a tube position of the X-ray tube;

a drive controller configured to change the tilt angle and the tube position depending upon the tilt angle and tube position inputted by the positioning device;

a tomographic image generator configured to perform a tomographic imaging of a subject in which X-rays forming a cone beam are irradiated from the X-ray tube aligned by the drive controller to the multi-slice detector aligned by the drive controller, and to generate tomographic images based upon the tomographic imaging;

an image data storage device configured to store image data based upon the tomographic images;

a three-dimensional image processor configured to determine an image-taking direction depending upon the tilt angle and the tube position, to perform a three-dimensional image processing on the image data and to generate a three-dimensional image, for display, in a line-of-sight direction corresponding to the image-taking direction;

a mode switcher configured to switch the mode only between a transmission mode and the CT mode;

a transmission image generator configured to perform a transmission imaging of the subject in which the X-rays are irradiated from the aligned X-ray tube to the aligned multi-slice detector, and to generate a transmission image based upon the transmission imaging, in the image-taking direction, corresponding to the line-of-sight direction of the displayed three-dimensional image generated by the CT mode; and

a transmission image displayer configured to display transmission image in substantially real-time.

7. The X-ray CT apparatus according to claim 6, wherein the positioning device is configured to input at least one of height, widthwise and longitudinal positions of a couch plate, the drive control being configured to determine a line-of-sight direction for the three-dimensional image processing depending upon at least one of the height, widthwise and longitudinal positions of the couch plate inputted by the positioning device.

8. The X-ray CT apparatus according to claim 6, wherein the three-dimensional image processor and the drive controller are configured to make a generation process of three-dimensional image data and to change the tilt angle and the tube position, in conjunction with an input to the input device.

9. The X-ray CT apparatus according to claim 6, wherein the multi-slice detector includes a plurality of arrays each of which has a plurality of X-ray detecting elements matched to a spread of the X-ray cone beam.

10. An X-ray radiographic method by using an imager system configured to include a table-top and a gantry which has at least an X-ray tube and a multi-slice detector, comprising:

mode setting to set a mode in a CT mode;

inputting a line-of-sight direction;

tomographic imaging performing to perform a tomographic imaging of a subject in which X-rays forming a cone beam are irradiated from the X-ray tube to the multi-slice detector;

tomographic image generating to generate tomographic images based upon the tomographic imaging;

image data storing to store image data based upon the tomographic images;

three-dimensional image processing to perform a three-dimensional image processing on the image data and to generate a three-dimensional image, for display, corresponding to a line-of-sight direction inputted;

mode switching to switch the mode only between a transmission mode and the CT mode;

drive controlling to control an alignment of an imager system depending upon an image-taking direction corresponding to the line-of-sight direction;

transmission image generating to perform transmission imaging of the subject in which the X-ray are irradiated from the X-ray tube aligned by the drive controlling to the multi-slice detector aligned by the drive controlling, and to generate a transmission image, based upon the transmission imaging, in the image-taking direction corresponding to the line-of-sight direction of the displayed three-dimensional image generated by the CT mode; and

transmission image displaying to display the transmission image in substantially real-time.

11. The X-ray radiographic method according to claim 10, further comprising:

line-of-sight direction operating that, when establishing a predetermined portion of the three-dimensional image, operates in a line-of-sight direction to display the predetermined portion with magnification, whereby the drive control aligning is effected by inputting the line-of-sight direction.

12. The X-ray radiographic method according to claim 10, wherein the three-dimensional image processing uses at least one of a volume rendering process, a surface rendering process, a MPR (multi planar reconstruction) process, a CVR (computed volume radiography) process and a MIP (minimum intensity projection) process.

13. The X-ray radiographic method according to claim 10, wherein at least one of a tube position of an X-ray tube, a tilt angle of a gantry and a position of a couch plate is used as a position of the imager system.

14. The X-ray radiographic method according to claim 10, further comprising:

three-dimensional image displaying that displays, as a three-dimensional image, three-dimensional image data as to the line-of-sight direction.

15. The X-ray radiographic method according to claim 10, wherein a virtual opening degree of a collimator of the imager system is regulated on a three-dimensional image displayed in the three-dimensional image displaying, the opening degree of the collimator of the imager system being inputted according to the virtual opening degree after regulating to effect the drive controlling.

16. The X-ray radiographic method according to claim 14, wherein the three-dimensional image processing includes properly generating three-dimensional image data, for display, corresponding to a post-change line-of-sight direction in conjunction with a change of a line-of-sight direction done on a screen for establishing a position of the imager system.

17. The X-ray radiographic method according to claim 16, wherein the position of the imager system is established based on a numeral representative of a position of the imager system, on the screen.

18. The X-ray radiographic method according to claim 14, wherein the three-dimensional image processing includes properly generating three-dimensional image data, for display, corresponding to a post-change line-of-sight direction in conjunction with a change of a line-of-sight direction done on a screen of a three-dimensional image displayed in the three-dimensional image displaying.

19. The X-ray radiographic method according to claim 18, wherein the line-of-sight direction inputting is prohibited from establishing an image-taking direction when a transmission image cannot be acquired in the imager system.

20. The X-ray radiographic method according to claim 14, wherein three-dimensional image processing includes determining a line-of-sight direction for taking an image of a sectional plane orthogonal to a direction designated by using the three-dimensional image, on a screen of a three-dimensional image displayed in three-dimensional image displaying, and to generate three-dimensional image data, for display, corresponding to the line-of-sight direction.

21. The X-ray radiographic method according to claim 20, wherein the direction designated is taken as a blood vessel extending direction.

22. The X-ray radiographic method according to claim 10, further comprising:

transmission image displaying that displays the transmission image.