An X-ray CT device and a computing unit to use a projection-based method for image reconstruction are included. The computing unit sets a coordinate space having coordinate axes of the thicknesses of base materials and likelihood the thicknesses, and then based on X-ray attenuation responses, executes: a first search to search in a direction perpendicular to a ridge direction of likelihood contours for a first estimated thickness having the highest likelihood, starting with an estimated thickness input value set in the coordinate space; a second search to search for a second estimated thickness having the highest likelihood, starting with a shifted starting point at a position shifted from the estimated thickness input value; and a third search to search on a line connecting the first estimated thickness with the second estimated thickness for the highest likelihood estimator having the highest likelihood, to obtain an estimated thickness output value.

A radiation image processing device includes: a first estimation section that estimates components of radiation Ra having passed through a subject Obj using a first radiation image taken from the subject Obj; a second estimation section that estimates components of the radiation Ra, which have passed through an additional scattering element EL, using an estimation result of the first estimation section and scattering characteristics f2(X) of the additional scattering element EL; and a first image generation section that generates a second radiation image, which has been transmitted through the subject Obj and the additional scattering element EL, using an estimation result of the second estimation section.

An apparatus including an x-ray source and detector where the source is disposed behind the detector and the detector is configured with a hole through which an x-ray beam emitted by the source can be transmitted to target tissue is provided. During operation, the source emits an x-ray beam through the hole in the detector. The x-ray beam may then be incident on an area of a subject to be imaged and cause various reflections and/or absorptions. The detector can detect signals reflected by the subject and an x-ray image can be generated accordingly.

A method of scanning parameter optimization, which method may be useful with image-guided radiation therapy (IGRT), allows for controlling exposure of a beam from an x-ray source and/or controlling the detection mechanism for an x-ray detector of imaging radiation of a radiation-delivery device based on one or more parameters of a region of interest of a patient. The one or more parameters of the region of interest may include a dimension, outer contour, density, location relative to an outlet of the beam, location relative to isocenter, location to the whole patient body, etc. Exposure of the patient to the beam may be varied via modulation of one or more scanning parameters for controlling an aspect of the beam and/or the detector to provide for targeted and or reduced radiation exposure of the patient or portion of the patient, and/or for improved quality of guiding images. The modulation may be varied depending on a view angle of the region of interest from a portion of the radiation-delivery device.

Systems and methods for obtaining scattering images during computed tomography (CT) imaging are provided. Two gratings or grating layers can be disposed between the object to be imaged and the detector, and the gratings or grating layers can be arranged such that primary X-rays are blocked while scattered X-rays that are deflected as they pass through the object to be imaged reach the detector to generate the scattering image.

An auxiliary device attachable to a mammography machine having an X-ray source and an X-ray receptor having a receptor area. The auxiliary device includes a housing having a length, width, and thickness, wherein the length and width of the housing are adapted to a length and width of the receptor area. The auxiliary device further includes one or more attachments for attaching the auxiliary device to the mammography machine, and a detector inside the housing. The detector includes a slab of semiconductor material, an electrode on a first side of the slab, and a pixelated electrode detector on the second side of the slab, and a read-out circuit bonded to the pixelated electrode detector, and the read-out circuit being configured for spectral photon counting with two or more energy bins. Methods for medical imaging are also provided.

A radiation diagnostic device according to an aspect of the present invention includes a first detector, a second detector, and processing circuitry. The first detector detects Cherenkov light that is generated when radiation passes. The second detector is disposed to be opposed to the first detector on a side distant from a generation source of the radiation, and detects energy information of the radiation. The processing circuitry specifies Compton scattering events detected by the second detector, and determines an event corresponding to an incident channel among the specified Compton scattering events based on a detection result obtained by the first detector.

An x-ray imaging apparatus and associated methods are provided to receive measured projection data from a wide aperture scan of a wide axial region and a narrow aperture scan of a narrow axial region within the wide axial region and determine an estimated scatter in the wide axial region using an optimized scatter estimation technique. The optimized scatter estimation technique is based on the difference between the measured scatter in the narrow axial region and the estimated scatter in the narrow axial region. Kernel-based scatter estimation/correction techniques can be fitted to minimize the scatter difference in the narrow axial region and thereafter applying the fitted (optimized) kernel-based scatter estimation/correction to the wide axial region. Optimizations can occur in the projection data domain or the reconstruction domain. Iterative processes are also utilized.

This X-ray imaging apparatus (100) includes a rotation mechanism (8) for relatively rotating an imaging system (200) constituted by an X-ray source (1), a detector (5), a first grating (2) and a second grating (3), and an image processing unit (6) for generating a dark-field image based on an X-ray intensity distribution at each of a plurality of rotation angles. The image processing unit (6) is configured to perform a scattering correction for reducing a dark-field signal of a pixel whose dark-field signal is larger than a threshold value (V1) among a plurality of pieces of pixels in the dark-field image to a set value (V2).

Multimodal imaging apparatus and methods include a rotatable gantry system with multiple sources of radiation comprising different energy levels (for example, kV and MV). Fast slip-ring technology and helical scans allow data from multiple sources of radiation to be combined or utilized to generate improved images and workflows, including for IGRT. Features include increasing the precision of spatial registrations between respective image sets to allow more precise radiation treatment delivery, reducing image artifacts (e.g., scatter, metal and beam hardening, image blur, motion, etc.), and utilization of dual energy imaging (e.g., for material separation and quantitative imaging, patient setup, online adaptive IGRT, etc.).