Abstract: A lung phantom unit for radiotherapy according to an embodiment of the present disclosure may arrange, at a location not affected by a magnetic field, a phantom driving cylinder and a driving device which may move a lung mimic and a tumor mimic in a lung simulation block. The lung phantom unit may be used for general purpose even as a phantom for MRI-based and CT image-based radiotherapy. Since lung and tumor motions are implemented by air injection, it may be possible to precisely measure the motion and volume change of a lung according to subtle changes in air pressure so that customized radiotherapy suitable for a patient having various breathing patterns is possible.

Abstract: A calibration phantom for radiometric characterization and/or radiotherapy dose calculation of a subject is provided, which includes an ellipsoid base having a primary volume defining a plurality of cylindrical voids, each of said cylindrical voids configured to receive a cylindrical insert having a diameter, wherein the ellipsoid base, the primary volume, and each of said inserts are formed from a tissue substitution material independently selected to approximate a radiological property of an anatomical feature of the subject to which the ellipsoid base, the primary volume, and each of said inserts corresponds, wherein the radiological property of the tissue substitution material, the diameter of each of said inserts, and a location of each of said inserts within the ellipsoid base are selected to mimic beam hardening upon exposure of the calibration phantom to a radiation beam. Optionally, one or more peripheral rings are disposed concentrically about the ellipsoid base.

Abstract: Provided is a simulation phantom including a simulated target volume and a simulated normal tissue encasing the simulated target volume, wherein the simulated target volume and a portion of the simulated normal tissue abutting the simulated target volume have a first characteristic to enable the simulation phantom to be imaged on a first imaging device, and the simulated target volume and the portion of the simulated normal tissue abutting the simulated target volume further have a second characteristic to enable the simulation phantom to be imaged on a second imaging device different from the first imaging device.

Abstract: A measurement apparatus includes: a flow path device including a first flow path in which first liquid including particles to be measured is flowed, and which includes a measurement region measured with an optical sensor, a second flow path in which second liquid for comparison is flowed, and which includes a comparison region measured with the optical sensor, and a calibration region for calibrating the optical sensor; an arm-like member in which the optical sensor is disposed in a first end, and in which a drive shaft is disposed in a second end; and a rotary drive actuator configured to rotationally drive the arm-like member in a predetermined range, wherein each of the measurement region, the comparison region, and the calibration region is disposed as a region including a position on a circumference along which the optical sensor moves in accordance with a rotary drive of the arm-like member.

Abstract: Provided is a 3D bone density and bone age calculation apparatus using an artificial intelligence-based rotation manner. The 3D bone density and bone age calculation apparatus includes a main body, and the main body includes a rotary drum including a drum shaft gear, an X-ray generator, an intensifying screen, and an image data capturer, a drum driver including a motor shaft gear connected to the drum shaft gear so as to rotate the rotary drum, a motor, support rollers and one of an origin sensor and an encoder, an outer case and an inner case, a front case and a rear case, a capturing holder, and a controller configured to select an image-captured position of the rotary drum, and configured to input a current age, sex and nutritional status of a patient, etc. The controller includes a display configured to display captured images and a diagram indicating bone age.

Abstract: A method for determining at least one artifact calibration coefficient is provided. The method may include obtaining preliminary projection values of a first object. The radiation rays may be detected by at least one radiation detector. The method may further include generating a preliminary image of the first object based on the preliminary projection values of the first object and generating calibrated projection values of the first object based on the preliminary image. The method may further include determining a relationship between the preliminary projection values and the calibrated projection values. The method may further include, for each of the at least one radiation detector, determining a location of the radiation detector and determining an artifact calibration coefficient corresponding to the radiation detector based on the relationship between the preliminary projection values and the calibrated projection values and the location of the radiation detector.

Abstract: A method for determining a response of a spectrometric system for measuring ionizing x-ray or gamma-ray photons, the measuring system comprising: a radiation source, configured to emit ionizing radiation along an emission axis; a pixelated detector, which comprises pixels, each pixel being configured to detect radiation emitted by the radiation source, and to acquire thereof an energy spectrum, in a plurality of energy channels; the emission axis being an axis extending between the radiation source and the detector; the response of the measuring system taking the form of effective spectra, defined for each pixel, and in each energy band, the effective spectrum of a pixel, in an energy band, corresponding to an energy distribution of the photons detected, by the pixel, in the energy channel, in the absence of any object interposed between the source and the pixel.

Abstract: Various methods and systems are provided for spectral computed tomography (CT) imaging. In one embodiment, a method comprises performing a scan of a subject to acquire, with a detector array comprising a plurality of detector elements, projection data of the subject, generating corrected path-length estimates based on the projection data and one or more selected correction functions, and reconstructing at least one material density image based on the corrected path-length estimates. In this way, the fidelity of spectral information is improved, thereby increasing image quality for spectral computed tomography (CT) imaging systems, especially those configured with photon-counting detectors.

Abstract: A radiographic image capturing system includes: a mammography apparatus that emits radiation having a first energy to a subject and captures a first radiographic image with a radiation detector and emits radiation having a second energy greater than the first energy to the subject and captures a second radiographic image with the radiation detector and that captures the first radiographic image and the second radiographic image with a breast in a state in which a contrast medium using iodine is administered. The radiographic image capturing system includes a phantom for evaluation of the mammography apparatus that has a solid material containing at least one element, which has a value of a k absorption edge that is equal to or greater than the first energy and equal to or less than the second energy, as an image evaluation pattern simulating the contrast medium.

Abstract: A three-dimensional image quality indicator suitable for assessing the quality of a CT scan includes a pyramidal structure having a base, an apex, and a plurality of triangular faces extending from the base to the apex; at least two grooves in each triangular face, each groove tapering from a wide end at the base to a narrow end at the apex; and a land between each pair of adjacent grooves in each triangular face, each land tapering from the base to the apex. When a two-dimensional slice is taken in a plane parallel to the base of the pyramidal structure, the grooves are observable at the edges of the structure. The smallest observable groove width provides a measure of CT resolution.

Abstract: A computer-implemented method of deriving 3D image data of a reconstruction volume from a plurality of 2D projections by way of filtered back-projection is disclosed. An embodiment of the method includes receiving a plurality of 2D projections of an imaged object, each 2D projection corresponding to a projection plane; applying a filter to each of the 2D projections to yield filtered 2D projections; calculating a filtered back-projection density distribution from the filtered 2D projections; calculating at least one modified filtered back-projection density distribution indicative of outlier values included in the filtered 2D projections; and calculating a revised filtered back-projection density distribution as a weighted linear combination of the filtered back-projection density distribution and the at least one modified filtered back-projection density distribution.

Abstract: Described here are systems and methods for optimization techniques for automatically selecting x-ray beam spectra, energy threshold, energy bin settings, and other imaging technique parameters for photon-counting detector computed tomography (“PCCT”). The techniques described here are generally based on subject or object size, material of interest, and location of the target material. Advantageously, the optimizations can be integrated with different PCCT systems to automatically select optimal imaging technique parameters before scanning a particular subject or object.

Abstract: Disclosed herein is a radiation detector comprising: a scintillator configured to emit a second radiation upon receiving a first radiation from a pulsed radiation source, a plurality of pixels, and a controller; wherein each pixel is configured to detect the second radiation; wherein the pulsed radiation source is configured to emit the first radiation during a plurality of ON periods and configured not to emit the first radiation during a plurality of OFF periods; wherein the controller is configured to determine that the pulsed radiation source is at one of the ON periods or at one of the OFF periods; wherein the controller is configured to cause the pixels to integrate signals or not to integrate signals with determination that the radiation source is at one of the ON periods or at one of the OFF periods.

Abstract: A body phantom according to an embodiment includes a layered resin structure formed by combining a first material having a first refractive index and a second material having a second refractive index based on three-dimensional data that indicates an optical characteristic of a living body, wherein a mixing ratio of the second material to the first material to form the layered resin structure is a value corresponding to the optical characteristic.

Abstract: Disclosed herein is a radiation detector, comprising: a plurality of pixels, and a controller; wherein each pixel is configured to detect radiation emitted from a pulsed radiation source; wherein the pulsed radiation source is configured to emit radiation during a plurality of ON periods and configured not to emit radiation during a plurality of OFF periods; wherein the controller is configured to determine that the pulsed radiation source is at one of the ON periods or at one of the OFF periods; wherein the controller is configured to cause the pixels to integrate signals or not to integrate signals with determination that the radiation source is at one of the ON periods or at one of the OFF periods.

Abstract: A multi-purpose object for calibrating, monitoring and/or tracking a patient in a treatment system and/or a treatment planning system is described, the multi-purpose object being made of transparent material and defining an internal space having one or more targets, wherein an upper surface is coated so as to define a pattern of transparent markings. The interior of the multi-purpose object can be back lit to present a high contrast surface image for a patient treatment, tracking or monitoring system.

Abstract: A radiation therapy system delivers radiation treatment over a 360-degree arc and performs a prepended imaging process, in a single pass, via an extended rotation gantry. While rotating the gantry in one direction about a bore of the radiation system, the radiation system generates multiple images of a target volume disposed in the bore using an imaging X-ray source mounted on the gantry. Then, while continuing to rotate the gantry in the same direction, the radiation system delivers a treatment beam to the target volume using a treatment-delivering X-ray source mounted on the gantry, where the treatment beam is delivered from some or all of a 360-degree arc about the bore. Thus, the prepended imaging process and the delivery of radiation are performed in a single pass of the gantry about a target volume, eliminating the need for a return stroke of the gantry for completion.

Abstract: A method for determining a CT system parameter: controlling a mould body to move between an X-ray source and a detection surface of a detector, and acquiring X-ray projections of the mould body during movement on the detection surface, wherein the mould body has a first plane and a second plane perpendicular to each other, and the first plane and the second plane are always perpendicular to the detection surface during the movement of the mould body; determining a first straight line and a second straight line according to the acquired X-ray projections; and determining an intersection point of the first straight line and the second straight line as a pedal coordinate of a focus of the X-ray source on the detection surface, a CT coordinate system parameter including the coordinates of the foot of the perpendicular.

Abstract: A lung motion phantom device and method of operation. The device has a body having an outer shell and a lung insert, a first actuator connected to a first drive linkage for driving a first displacement of an internal volume of the lung insert and an outer surface of the outer shell in a first direction, a second actuator connected to a second drive linkage for driving a second displacement of the internal volume of the lung insert and the outer surface of the outer shell in a second direction different than the first direction, and a controller programmed to control the first and second actuators such that the first and second displacements simulate movement of an external surface and an interior of a thoracic region of a patient.

Abstract: Virtually every cancer patient is imaged with CT, PET or MRI. Importantly, such imaging reveals that tumors are complex and heterogeneous, often containing multiple habitats within them. Disclosed herein are methods for analyzing these images to infer cellular and molecular structure in each of these habitats. The methods can involve spatially superimposing two or more radiological images of the tumor sufficient to define regional habitat variations in two or more ecological dynamics in the tumor, and comparing the habitat variations to one or more controls to predict the severity of the tumor.

Abstract: Described is a dynamic phantom. The phantom comprises a body having a front, a back, and an internal cavity between the front and the back, the body having a movable chest wall. The phantom also comprises a first motion mechanism that is actuated to move the chest wall to thereby move the front relative to the back of the body. The phantom also comprises a moveable organ member supported within the internal cavity that is caused to move relative to the body by a second motion mechanism. The phantom also comprises a drive source for driving the first and second motion mechanisms, wherein the first and second motion mechanisms move the chest wall and the moveable organ member to substantially represent their movement in a human body.

Abstract: A beam hardening correction method, a related calibration method for tomographic image data and a related apparatus. The tomographic image data includes attenuation data (f) and phase gradient data (g) and/or small angle scattering data (h). A correction value is computed from the attenuation data (f) by applying a function (q) to the attenuation data (f). The correction value is combined (S445) with the phase gradient data (g) or with the small angle scattering data (h).

Abstract: The present invention relates to systems and methods for adaptively optimizing broadband reference spectra for a multi-spectral image or adaptively optimizing reference colors for a bright-field image. The methods and systems of the present invention involve optimization techniques that are based on structures detected in an unmixed channel of the image, and involves detecting and segmenting structures from a channel, updating a reference matrix with signals estimated from the structures, subsequently unmixing the image using the updated reference matrix, and iteratively repeating the process until an optimized reference matrix is achieved.

Abstract: A guide device for at least one line, such as an electric line of a C-arm, has a rotatable first cylinder with a first cylindrical surface and a static second cylinder, adjoining the first cylinder in the axial direction and having a second cylindrical surface. A first guide element for guiding the line on the first and/or the second cylindrical surface, is disposed coaxially with respect to the first and the second cylinder and it is movable relative to the first and the second cylinder. The line can be wound up on the first and/or the second cylindrical surface or can be unwound therefrom depending on the movement of the first cylinder.

Abstract: The present invention is directed towards spectral imaging, wherein a dedicated spectral imaging phantom is scanned with a spectral x-ray device to obtain spectral imaging data of the spectral imaging phantom. Said imaging data of the spectral imaging phantom is used as input for obtaining improved further imaging data of a subject of which a spectral scan is performed subsequent to or simultaneous with the spectral scan of the spectral imaging phantom. Improved further imaging data may be obtained by using the spectral phantom imaging data as input for imaging data correction, for providing a recommendation and/or for further data processing.

Abstract: Apparatuses are provided for evaluating an image quality of an image produced by an x-ray computed tomography (CT) system.

Abstract: Methods and devices for detecting consistency between an invisible radiation field and a visible light field are provided. In an example, the method includes: an invisible radiation field is obtained by controlling a size of an opening of a beam limiting device; a first projection image is captured by an Electron Portal Imaging Device (EPID) as a distribution map of the invisible radiation field; a visible light field is obtained by turning on a light field lamp without changing the size of the opening of the beam limiting device; a phantom is positioned at each of vertices of the visible light field; a second projection image is captured by the EPID as a vertex distribution map of the visible light field; and deviation information between the invisible radiation field and the visible light field is determined according to the distribution map of the invisible radiation field and the vertex distribution map of the visible light field.

Abstract: A deformable radiotherapy phantom can be produced using an additive manufacturing process, based on a medical image of the patient. The deformable phantom can include dosimeters for measuring radiation dose distribution. A smart material can allow deformation in response to an applied stimulus. Among other things, the phantom can be used to validate radiation dose warping, a radiotherapy treatment plan, to determine a maximum acceptable deformation of the patient, to validate a cumulative accuracy of dose warping and deformable image registration, or the like.

Abstract: A radiation exposure system having a beam source is provided. The system further includes a variable thickness degrader, positioned between the beam source and an object to be exposed, for providing varying degrees of degradation to a radiation beam emitted from the beam source onto the object. The system also includes a set of detectors, positioned between the variable thickness degrader and the object, for receiving and measuring only a portion of the radiation beam remaining after the degradation of the radiation beam by the variable thickness degrader.

Abstract: A method of making a gauge for verifying or calibrating an x-ray computed tomography device positions a first plurality of objects on a first substrate, and a second plurality of objects on a second substrate. The method also certifies the positions of both the first plurality of objects on the first substrate, and the second plurality of objects on the second substrate. After certifying both the first and second plurality of objects, the method couples the first substrate with the second substrate.

Abstract: A method is described for the determination of a calcium score for a patient to be examined with the aid of a CT system. The method is used to define patient-specific CT-acquisition parameters. In addition, material parameters for a model method for the generation of synthetic image data for virtual CT-acquisition parameters are calibrated using phantom image data recorded with reference CT-acquisition parameters. A calcium score assigned to synthetic phantom image data corresponds to a calcium score determined with phantom image data recorded with reference CT-acquisition parameters. Next, CT-projection-measurement data is acquired for a region of interest using the patient-specific CT-acquisition parameters. The acquired CT-projection-measurement data is used to generate synthetic image data using the calibrated model method. Finally, a calcium score is determined using a standard method on the basis of the synthetic image data. Also described is a calcium-score-determining device.

Abstract: Method and apparatus are provided for calibration or verification of accuracy specification of a computed tomographic system. In one embodiment, the apparatus can include a base structure, a first set of test objects arranged along a first axis and coupled to the base structure, and a second set of test objects arranged along a second axis and coupled to the base structure. The first set of test objects and the second set of test objects have a first geometry. The apparatus can also include a third set of test objects and a fourth set of test objects. The third set of test objects, and the fourth set of test objects have a second geometry different from the first geometry. Locations of the first, second third and fourth set of test objects are spatially fixed with respect to the base structure. The apparatus is a test specimen adapted for calibration or accuracy verification of computed tomography system.

Abstract: A computerized tomography artifact correction method includes: receiving scanning data; reconstructing an image to be corrected and a reference image of the image to be corrected based on the scanning data; determining proportions of a first substance for pixels of the reference image; obtaining a base image of the first substance based on the proportions of the first substance; performing a projection of the base image of the first substance and the reference image to obtain a plurality of projection lines; for each of the plurality of projection lines, obtaining an equivalent length of the first substance corresponding to the projection line and selecting a hardening correction coefficient based on the equivalent length of the first substance corresponding to the projection line; and performing an artifact correction on the image to be corrected based on the hardening correction coefficients.

Abstract: The present invention relates to phantom device for a dark field imaging system. Although dark field imaging is known to be sensitive to changes in the micro-structure of the tissue of a human subject that may be caused during a disease progression, there may be a need to quantify information provided by an image of the human subject. A detector signal component representing the dark image may be altered by changes of the X-ray spectrum which passes tissue of the human subject comprising micro-structures. This may be caused due to an attenuation of the X-ray radiation previously provided by an X-ray source, wherein the attenuation may be caused by tissue of the human subject, which covers said micro-structure comprising tissue. In order to provide information in clinical practice regarding the influence of attenuation to the X-ray radiation before it passes the micro-structure issue of the human subject, the phantom device for dark field imaging is proposed.

Abstract: A calibration phantom has a surface having a reflectance calibration target with a pattern that is indicative of one or more spatial reference positions. Radio-opaque markers are disposed in the calibration phantom and are positionally correlated to the one or more spatial reference positions of the reflectance calibration target.

Abstract: The invention concerns a thyroid phantom (1), the phantom comprising a body (2) comprising at least two parts (3, 4) defining between them an imprint (7) of a thyroid and means for attaching the two parts together in order to close the imprint in a sealed manner, the phantom further comprising means for filling the imprint with a solution, said filling means comprising at least one channel (19, 20) extending from the outside of the body into the imprint and means for temporarily symmetrically plugging said channel. The invention also concerns a method for producing such a thyroid phantom, a family comprising a plurality of such thyroid phantoms corresponding to different categories of human beings, an overall phantom comprising one such thyroid phantom as well as a family comprising a plurality of overall phantoms.

Abstract: A coordinate system registration module, including radiopaque elements arranged in a fixed predetermined pattern and configured, in response to the radiopaque elements generating a fluoroscopic image, to define a position of the module in a fluoroscopic coordinate system of reference. The module further includes one or more connections configured to fixedly connect the module to a magnetic field transmission pad at a predetermined location and orientation with respect to the pad, so as to characterize the position of the registration module in a magnetic coordinate system of reference defined by the magnetic field transmission pad.

Abstract: A system includes determination of a first sub-matrix of a projection matrix which describes a geometrical relationship between points of a three-dimensional coordinate system of the imaging system and points of a two-dimensional coordinate system of an image detector, determination of a second sub-matrix of the projection matrix, where the first and second sub-matrixes comprise a decomposition of the projection matrix, conversion of a first point of the two-dimensional coordinate system to a first point of the three-dimensional coordinate system based on the first and second sub-matrixes, determination of an updated first sub-matrix of an updated projection matrix, where the updated projection matrix describes a second geometrical relationship between points of the three-dimensional coordinate system and points of the two-dimensional coordinate system, and conversion of a second point of the two-dimensional coordinate system to a second point of the three-dimensional coordinate system based on the updated fi

Abstract: Techniques are disclosed for estimating patient radiation exposure during computerized tomography (CT) scans. More specifically, embodiments of the invention provide efficient approaches for generating a suitable patient model used to make such an estimate, to approaches for estimating patient dose by interpolating the results of multiple simulations, and to approaches for a service provider to host a dose estimation service made available to multiple CT scan providers.

Abstract: One aspect of the invention provides a phantom including a confined fluidic path defining a plurality of regions of monotonically decreasing, discrete cross-sectional dimensions with respect to an imaging plane. Another aspect of the invention provides a method of assessing imaging. The method includes: placing a phantom as described herein within an imaging system; flowing one or more fluids through the phantom; and capturing one or more images of the phantom. Another aspect of the invention provides a kit for assessing imaging. The kit includes a phantom as described herein and instructions for use.

Abstract: Among other things, one or more techniques and/or systems for calibration of a radiation system to compute a gain correction(s) are provided. A calibration procedure is performed during which a portion of the detector array is shadowed by an object, causing the detector array to be non-uniformly exposed to radiation. A portion of a projection generated from the calibration procedure and indicative of radiation that did not traverse the object is separated from a portion of the projection indicative of radiation that did traverse the object, and a gain correction(s) is computed from the portion of the projection indicative of radiation that did not traverse the object (e.g., and is thus indicative of radiation that merely traversed air).

Abstract: The present invention relates to systems and methods for adaptively optimizing broadband reference spectra for a multi-spectral image or adaptively optimizing reference colors for a bright-field image. The methods and systems of the present invention involve optimization techniques that are based on structures detected in an unmixed channel of the image, and involves detecting and segmenting structures from a channel, updating a reference matrix with signals estimated from the structures, subsequently unmixing the image using the updated reference matrix, and iteratively repeating the process until an optimized reference matrix is achieved.

Abstract: The present invention relates to an external standard reference system of a type inserted into the coil of a human magnetic resonance imaging equipment, and more specifically, to a system capable of analyzing metabolic components (quantity of metabolites) in a human body without an error and a limited range using an external standard reference analysis method, in order to enhance accuracy of diagnosis by utilizing magnetic resonance spectroscopy of the human magnetic resonance imaging equipment. A system for evaluating performance of magnetic resonance spectroscopy includes an outer container for inserting an RF coil and provided with a plurality of holes; a plurality of inner containers arranged to be inserted into the plurality of holes respectively and capable of being filled with metabolites different from each other in at least a type or a concentration; and a frame for fixing a head of an object arranged inside the outer container.

Abstract: A breast imaging apparatus includes a gantry which includes a radiation generation unit configured to generate radiation and a radiation detection unit configured to detect radiation generated by the radiation generation unit, the radiation generation unit and the radiation detection unit being capable of rotating facing each other, wherein the gantry is provided with a front cover configured to protect a subject from the radiation generation unit and the radiation detection unit which rotate during CT imaging, and the front cover has an opening in which the breast of the subject is inserted, and a breast holding portion configured to hold the breast of the subject inserted in the opening.

Abstract: A method for image reconstruction is disclosed, based upon a first plurality of spectral raw data sets. The method includes forming a second plurality of virtual raw data sets; reconstructing an auxiliary image data set on the basis of a virtual raw data set. A first material is selected from a material group which comprises a plurality of materials. Material-specific maps are generated for a number of second materials of the material group. A determination of material line integrals take place, for the second materials with forward projection of the respective material-specific map. Subsequently, synthetic projection data sets are determined for each material. Finally, a reconstruction of at least one image data set takes place on the basis of the synthetic projection data sets for a number of materials of the material group. An image reconstruction device and a computed tomography system are also disclosed.

Abstract: In a system having a thermal backdrop (106) and a thermal illuminator (102), the thermal backdrop includes a body having a top face; a contrast phantom (114) positioned above the top face and aligned substantially parallel with the top face; and a reflective layer (112) located between the body and the contrast phantom and aligned substantially parallel with the top face. The thermal illuminator radiates thermal energy (104) in a first direction towards the contrast phantom; wherein the first direction is aligned with the top face such that when the thermal energy is radiated in the first direction a first portion of the thermal energy is absorbed by the contrast phantom and a second portion (116) is reflected by the reflective layer towards a millimeter-wave camera (118) in a second direction. Furthermore, the contrast phantom has a plurality of different portions (114A, 114B, 114C, 114D), each portion having a different respective thickness along the first direction.

Abstract: The disclosure relates to systems and method for processing images. The method includes selecting a predetermined reference structure, the predetermined reference structure having a known feature size/shape. The method also includes obtaining a reference image of the predetermined reference structure, and capturing a calibration image of the predetermined reference structure using an observation device. The calibration image includes a plurality of features. Additionally, the method includes identifying at least one portion of the plurality of features of the calibration image that include a feature size/shape substantially similar to the known feature size and shape of the predetermined reference structure. Finally, the method includes combining the identified portion of the plurality of features of the calibration image to form a stacked feature image, and determining a point spread function (PSF) of the observation device by comparing the obtained reference image with the stacked feature image.

Abstract: The invention provides a sensitivity correction coefficient calculating system for an X-ray detector with which the sensitivity correction coefficient can be calculated using a multipurpose X-ray source instead of a specific X-ray source. In the sensitivity correction coefficient calculating system for an X-ray detector having a detection surface where detection elements for detection the X-ray intensity are aligned one-dimensionally or two-dimensionally, fitting is carried out on the measured X-ray intensity detected by a detection element using an approximation function so as to calculate the sensitivity correction coefficient using the calculated X-ray intensity calculated from the approximation function and the measured X-ray intensity.

Abstract: A test pattern geometrically calibrates an x-ray imaging device to generate three-dimensional images of an object by reconstruction based on two-dimensional projections of the object, the calibrating test pattern comprising a volume support with markers having a radiological absorbance providing contrast to the volume support, the markers distributed in a three-dimensional pattern, in subsets substantially in parallel respective straight lines wherein sequences of cross-ratios are constructed from the respective subsets of markers. Each sequence of cross-ratios comprises a single cross-ratio for each quadruplet of markers in which quadruplet the markers are ordered depending on rank number of respective markers along the straight line they are aligned in a predefined first direction, the order being common to all cross-ratios.

Abstract: The present invention relates to a method for reconstructing a 3D image from 2D X-ray images acquired with an X-ray imaging system, said method comprising the steps of: a) receiving a set of 2D X-ray images of a region of a patient with said X-ray imaging system, b) computing an initial 3D image within the coordinate system of the X-ray imaging system by using at least part of said 2D X-ray images with their respective projective geometry data; c) projecting said initial 3D image on at least part of said 2D X-ray images and adjusting the respective projective geometry data of said images, said adjustment comprising registration of said images with the projection of the initial 3D image using an image-to-image registration technique; d) computing an updated 3D image using the complete set of 2D X-ray images with their respective adjusted projective geometry data.