35 results about "Ct measurements" patented technology

An embodiment in accordance with the present invention provides a device and method for a quantitatively calibrated computed tomography scanner. The device includes a gantry configured for receiving a patient or part of a patient. The gantry includes an X-ray source and a detector positioned opposite said X-ray source, such that said detector receives the X-rays emitted from the X-ray source. Calibration phantoms are integrated with the gantry and / or a device within the scanner so as to allow for calibration in quantitative CT measurements of Hounsfield units and / or bone mineral density.

In a multi-source X-ray CT scanner having multiple X-ray sources, an imaging FOV size is fixed. In the X-ray CT scanner, a position of at least one of multiple X-ray generators is movable in the Z-axis direction (in the rotation axis direction). It is further possible to configure such that while shifting the X-ray generator, the rotation speed of the rotating plate is kept to be a predetermined value or less. Highly precise CT measurement is implemented as to various imaging FOV sizes, without exposing the test subject to ineffective radiation.

An embodiment in accordance with the present invention provides a device and method for a quantitatively calibrated computed tomography scanner. The device includes a gantry configured for receiving a patient or part of a patient. The gantry includes an X-ray source and a detector positioned opposite said X-ray source, such that said detector receives the X-rays emitted from the X-ray source. Calibration phantoms are integrated with the gantry and / or a device within the scanner so as to allow for calibration in quantitative CT measurements of Hounsfield units and / or bone mineral density.

The present invention provides a method for correcting CT radiation hardening in a multiphase flow system, comprising the following steps: 1) using fluid mechanics software to generate a simulated flow field of the multiphase flow system; 2) selecting a two-dimensional section of the simulated flow field, Obtain the flow field data of this two-dimensional cross-section; 3) select the material and thickness of different filter discs, simulate the process that CT scans the described two-dimensional cross-section, and obtain the simulated two-dimensional cross-section corresponding to different filter disc materials and thicknesses respectively. Reconstructing the image; 4) determining the material and thickness of the filter required for actual CT measurement according to the degree of approximation between each simulated two-dimensional reconstructed image and the simulated flow field data. The advantage of the present invention is that, by combining computational fluid dynamics with CT simulation, the shortcoming of being unable to produce an accurate and repeatable flow field in physical experiments can be overcome; and the present invention can determine the hardening correction parameters of the CT system through computer simulation, thereby Save a lot of manpower, material and financial resources.

Renal extraction fraction (EF) is determined through use of computed tomography (CT) measurements of arterial blood before and after injection of a radiographic contrast agent into the blood and CT measurements of renal vein blood after injection of the radiographic contrast agent.

The invention relates to a method for measuring area changes of CO2-saline water interfaces in a porous medium by using a CT. The method comprises the steps of firstly preparing saline water containing potassium iodide to strengthen the image contrast of CO2-saline water; continuously scanning by using the CT to obtain unsteady-state porous medium images under the CO2-saturated condition and different injection conditions; removing a noisy point by using a filter and carrying out threshold processing to generate binary images only containing 0 and 1 of saturated CO2 and under different injection conditions; carrying out subtraction on two image stacks to obtain distribution areas of the saline water in the binary images; extracting the edges of the distribution areas of the CO2 and the saline water and determining a union set to generate binary image slice stacks of the CO2-saline water interfaces; obtaining the area changes of the CO2-saline water interface in the porous medium under different injection conditions through determining and measuring the area of disconnected CO2-saline water interfaces; and calculating the saturability of the saline water in each image slice stack and obtaining area change characteristic parameters of the CO2-saline water interfaces under different injection conditions through induction.

This application discloses a secondary current amplification coil of a current transformer, which is used in the CT vector measurement of the secondary side of the current transformer in the power system power generation process. The coil body, and the two ends of the wire are free ends with a length of N. When the secondary side CT vector measurement is performed under the condition of no-load operation of the transmission line, the current measured by the clamp phase meter through the coil body is M times the capacitive current generated to the ground under no-load conditions, and the phase The current measured by the meter meets the accuracy requirements, and the phase angle of the measured voltage remains unchanged. It can be seen that the secondary current amplification coil of the current transformer disclosed in this application can also perform CT on the secondary side under the condition of no-load operation of the transmission line. Vector measurement does not require switching operations, thereby improving measurement efficiency.

The invention provides an X-ray CT (Computed Tomography) measurement system for gas-water relative permeability, and belongs to the technical field of CO2 capture and storage. The X-ray CT measurement system comprises a sand filling pipe, a saline water / CO2 injection system, an X-ray CT imaging system, a computer data acquisition system, a liquid conveying system, a temperature control system, a vacuum pipe and a back pressure valve. A main body of the sand filling pipe is in an aluminum alloy structure so as to enhance the penetration of X-ray; upper and lower flange discs of a core barrel are in stainless steel structures and can be detached freely. The upper and lower flange discs are provided with dense stainless steel wire meshes so as to prevent sand from flowing into an experiment device. Sealing rings are arranged at the butt-joint parts of the upper and lower flange discs and the main body of the sand filling pipe and are used for sealing the sand filling pipe and the experiment device. According to the X-ray CT measurement system, the saturation level and the relative permeability of each phase of two-phase flows of CO2 and saline water in a porous medium can be measured efficiently and reliably; the interference problems of various influence factors in a measurement process of the saturation level and the relative permeability of the two phases including the CO2 and the saline water are solved.

A computed tomography device (CT device) includes a user interface, via which the standard settings characterizing the CT measurement can be performed. At the same time, in a method and a computed tomography device for carrying out this method, filtering behavior of the filter electronics is adapted to the configuration of the standard settings by the system computer.