X-ray CT system, gantry apparatus, console terminal, method of controlling them, and storage medium
AssigneeGE Medical Systems Global Technology Company, LLC
InventorTetsuya Horiuchi
Life of this patent
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Abstract
In order to obtain an X-ray tomographic image with high quality while minimizing the exposed dose to a subject by employing the most suitable filter according to the region of the subject to be scanned, a filter unit 6 having filters 6a-6c having different transmission properties are provided below an X-ray tube 4 in a gantry apparatus. To obtain an X-ray tomographic image, upon determining the scan region of the subject, a motor 7 is driven to position one of the filters corresponding to the scan region just below the X-ray tube 4 for employing the filter, and X-rays are applied to the subject through the filter.
Claims17
A system for controlling X-ray beams in an X-ray CT system having an X-ray generating source, an X-ray detecting section, a first filter unit disposed closest to said detecting section, and a second filter unit disposed closest to said source and between said source and said first filter unit, said first filter unit having a thin central portion and thick end portions to reduce X-ray attentuation at said central portion and enhance X-ray attenuation at the end portions, wherein said second filter unit is a flat plate having therein at least two filters, each having different X-ray transmission properties;
- and further comprising positioning means for selectively moving said second filter unit so that said X-ray beams are selectively directed through a selected one of said at least two filters and then through said first filter unit.
A method for controlling X-ray beams in an X-ray cT system having an X-ray generating source, an X-ray detecting section, a first filter unit disposed closest to said detecting section, and a second filter unit disposed closest to said source and between said source and said first filter unit, said first filter unit having a thin central portion and thick end portions to reduce X-ray attenuation at said central portion and enhance X-ray attenuation at the end portions, wherein said method comprises the steps of:
- providing as said second filter unit a flat plate having therein at least two filters, each having different X-ray transmission properties;
- and selectively moving said second filter unit while keeping said first filter unit fixed so that said X-ray beams are selectively directed through a selected one of said at least two filters of said second filter unit and then through said first filter unit.
A storage medium for storing a program code for providing instruction signals to a system for controlling X-ray beams in an X-ray CT system having an X-ray generating source, an X-ray detecting section, an operating device, a first filter unit disposed closest to said detecting section, and a second filter unit disposed closest to said source and between said source and said first filter unit, said first filter unit having a thin central portion and thick end portions to reduce X-ray attentuation at said center 1 portion and enhance X-ray attentuation at the end portions, wherein said second filter unit is a flat plate having therein at least two filters, each having different X-ray transmission properties;
- and positioning means for selectively moving said second filter unit so that said X-ray beams are selectively directed through a selected one of said at least two filters and then through said first filter unit, wherein said CT system performs reconstruction processing for an X-ray tomographic image based on data transferred from said detecting section, said storage medium storing a program code of a display step of displaying a menu for selecting a scan region of a subject, a program code of a decision step of deciding which of said at least two filters is to be used based on a selected scan region, and a program code of a step of supplying an instruction indicating the filter which is selected at said deciding step.
Dependencies are inferred from the claim text.