X-ray diagnostic apparatus comprising an X-ray filter movable along an imaging axis of X-rays

Patent metadata

Field	Value
Publication number	US-9848840-B2
Application number	US-201414480794-A
Country	US
Kind code	B2
Filing date	Sep 9, 2014
Priority date	Sep 19, 2013
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

According to one embodiment, an X-ray diagnostic apparatus includes an X-ray tube, an X-ray detection unit, an X-ray filter, an input unit, and an X-ray filter support unit. The X-ray tube generates X-rays. The X-ray detection unit detects the X-rays transmitted through a subject. The X-ray filter is arranged between the X-ray tube and the object and has an opening. The X-ray filter support unit supports the X-ray filter so as to make the X-ray filter movable in an imaging axis direction of the X-rays.

First claim

The invention claimed is:

1. An X-ray diagnostic apparatus comprising:
an X-ray tube configured to generate X-rays;
an X-ray detector configured to detect X-rays generated from the X-ray tube and transmitted through an object;
an X-ray filter configured to be arranged between the X-ray tube and the object and having an opening; and
an X-ray filter support unit configured to support the X-ray filter so as to make the X-ray filter movable along an imaging axis direction of the X-rays.

2. The X-ray diagnostic apparatus of claim 1 , further comprising another X-ray filter configured to be arranged at a position located between the X-ray tube and the object and shifted along the imaging axis with respect to the X-ray filter.

3. The X-ray diagnostic apparatus of claim 1 , wherein the X-ray filter support unit supports the X-ray filter so as to make the X-ray filter movable along two axes perpendicular to the imaging axis.

4. The X-ray diagnostic apparatus of claim 1 , further comprising an X-ray filter driving unit configured to rotate and move the X-ray filter about an axis parallel to the imaging axis.

5. The X-ray diagnostic apparatus of claim 1 , further comprising:
an X-ray filter driving unit configured to move the X-ray filter; and
an X-ray filter control unit configured to control the X-ray filter driving unit in accordance with a first range on a detection surface of the X-ray detector in which X-ray reception sensitivity is lower than X-ray reception sensitivity of a second range on the detection surface of the X-ray detector.

6. The X-ray diagnostic apparatus of claim 5 , wherein the X-ray filter control unit controls the X-ray filter driving unit in accordance with a change in dose distribution in the X-ray irradiation range to maintain an irradiation range corresponding to the opening in a range set in accordance with an instruction from a user.

7. The X-ray diagnostic apparatus of claim 5 , further comprising:
an image generation unit configured to generate data of an X-ray image concerning the object based on an output from the X-ray detector; and
a feature point extraction unit configured to extract a feature point from the X-ray image by threshold processing,
wherein the X-ray filter control unit controls the X-ray filter driving unit to include the extracted feature point in the irradiation range corresponding to the opening.

8. The X-ray diagnostic apparatus of claim 1 , wherein the X-ray filter includes a plurality of filter components.

9. The X-ray diagnostic apparatus of claim 8 , further comprising:
a filter component driving unit configured to move the plurality of filter components to change at least one of a position of the opening of the X-ray filter and a size of the opening; and
a filter component control unit configured to control the filter component driving unit.

10. The X-ray diagnostic apparatus of claim 9 , wherein the filter component control unit controls the filter component driving unit in accordance with a range of the X-ray detector in which X-ray reception sensitivity is low.

11. The X-ray diagnostic apparatus of claim 9 , wherein the filter component control unit controls the filter component driving unit in accordance with a change in dose distribution in the X-ray irradiation range to maintain an irradiation range corresponding to the opening in a range set in accordance with an instruction from a user.

12. The X-ray diagnostic apparatus of claim 1 , wherein the X-ray filter support unit moves according to change of an SID so as to maintain a ratio of the SID to a distance between an X-ray focal point and the X-ray filter.

13. An X-ray diagnostic apparatus comprising:
an X-ray tube configured to generate X-rays;
an X-ray detector configured to detect X-rays generated from the X-ray tube and transmitted through an object;
a plurality of types of X-ray filters configured to be arranged between the X-ray tube and the object; and
an X-ray filter support unit configured to support the plurality of types of X-ray filters so as to make the plurality of types of X-ray filters movable along an imaging axis direction of the X-rays,
wherein the plurality of types of X-ray filters include respective attenuation coefficients different from each other.

14. The X-ray diagnostic apparatus of claim 13 , further comprising a filter selection unit configured to select, from the plurality of types of X-ray filters with different attenuation coefficients, one of the plurality of types of X-ray filters which reduces a dose of X-rays reaching a range of the X-ray detector in which X-ray reception sensitivity is high to a dose lower than a predetermined dose, in accordance with examination information of the object.

15. A diagnostic method comprising the steps of:
arranging an X-ray filter between an X-ray tube and an object;
irradiating the object with X-rays using the X-ray tube;
detecting X-rays generated from the X-ray tube and transmitted through the object; and
moving the X-ray filter along an imaging axis direction of the X-rays.

16. The diagnostic method of claim 15 , wherein the moving step includes moving, according to change of an SID, the X-ray filter along the imaging axis direction of the X-rays so as to maintain a ratio of the SID to a distance between an X-ray focal point and the X-ray filter.

17. The diagnostic method of claim 15 , wherein the moving step includes moving the X-ray filter along the imaging axis direction of the X-rays so as to maintain a high-dose range of the X-rays in a first range on a detection surface of an X-ray detector, X-ray reception sensitivity of the first range being lower than X-ray reception sensitivity of a second range on the detection surface of the X-ray detector.

Assignees

• Toshiba Medical Sys Corp

Inventors

• Ohashi Shumpei
• Kobayashi Yoshimasa
• Watanabe Koichiro

Classifications

• A61B6/4042

  K-edge filters · CPC title

• A61B6/06

  Diaphragms · CPC title

• A61B6/4441

  the rigid structure being a C-arm or U-arm · CPC title

• A61B6/4035 Primary

  the source being combined with a filter or grating · CPC title

• A61B6/542

  involving control of exposure · CPC title