X-ray diagnostics device and method for controlling an X-ray diagnostics device
The invention relates to an x-ray diagnostics device having an x-ray tube for generating x-rays operated by a high voltage generator, having an x-ray detector for converting incident x-rays into electrical signals, having an image processing system and a control device for the duration of the x-ray pulse, in which parameters of the x-ray diagnostics device can be adjusted, with a computing unit being assigned to the control device, said computing unit determining the spatial frequency-dependent signal-to-noise ratio on the basis of the parameters and calculating therefrom the duration of the x-ray pulse and/or the remaining parameters required for a recording. The invention further relates to a method of this type for controlling the x-ray diagnostics device, in which the duration of the x-ray pulse is controlled such that the recognizability of relevant, moved objects is maximal.
1. An X-ray diagnostics device, comprising:
an X-ray tube for generating X-rays;
a high voltage generator for operating the X-ray tube;
an X-ray detector for converting X-rays received by the detector into electrical signals;
an image processing system;
a control device for adjusting a duration of X-ray pulses, the control device configured to adjust a plurality of operating parameters related to operating the X-ray diagnostics device; and
a computing unit assigned to the control device, the computing unit configured to determine a spatial frequency-dependent signal-to-noise ratio based on the operating parameters, wherein at least one of the following is adjusted by the control device based on the determined spatial frequency-dependent signal-to-noise ratio: 1) time duration of the X-ray pulses and 2) one or more imaging parameters for recording an X-ray image.
2. The X-ray diagnostics device according to claim 1 , further comprising a storage device for storing characteristics related to examination objects.
3. The X-ray diagnostics device according to claim 1 , further comprising a measuring device assigned to the control device for measuring a thickness of an examination object.
4. The X-ray diagnostics device according to claim 1 , further comprising a filter device for moving an optimized filter into a radiation path of the X-ray tube based on a calculation result processed by the computing unit.
5. The X-ray diagnostics device according to claim 1 , wherein electrical signals corresponding to sequential X-ray images are fed to the computing unit for determining a motion speed of an examination object.
6. The X-ray diagnostics device according to claim 1 , wherein the operating parameters are chosen from the group consisting of a tube voltage, a tube current, an X-ray pulse duration and a filter.
7. A method for controlling an X-ray diagnostics device having
an X-ray tube for generating X-rays and operated by a high voltage generator;
an X-ray detector for converting X-rays received by the detector into electrical signals;
an image processing system; and
a control device for controlling a duration of an X-ray pulse, the method comprising:
providing a moving examination object; and
adjusting the duration of the X-ray pulse such that an X-ray image quality related to an X-ray image recorded from the moving object is maximized, wherein the X-ray image quality is based on a spatial frequency-dependent signal-to-noise ratio, and further wherein at least one of the following is calculated based on the determined spatial frequency-dependent signal-to-noise ratio: 1) time duration of the X-ray pulses, and 2) one or more imaging parameters for recording the X-ray image.
8. The Method according to claim 7 , wherein a thickness of the examination object is postulated and used for adjusting the duration of the X-ray pulse without measuring the thickness.
9. The method according to claim 7 , wherein a thickness of the examination object is determined from a Water Equivalent of the examination object.
10. The method according to claim 7 , wherein a thickness of the examination object is measured and used for adjusting the duration of the X-ray pulse.
11. The method according to claim 10 , wherein the thickness is measured by mechanical limiters, light sensors or electro-magnetic sensors.
12. The method according to claim 7 , wherein a motion speed of the examination object is postulated without measuring the motion speed.
13. The method according to claim 7 , wherein a motion speed of the examination object is determined from an organ program.
14. The method according to claim 7 , wherein a motion speed of the examination object is determined by comparing at least two sequential X-ray images recorded from the moving examination object.