Abstract: The invention relates to a method of determining a spatial distribution of magnetic particles in an examination area, in which a magnetic field is generated which has a first part-region having a relatively low magnetic field strength and a second part-region having a relatively high magnetic field strength. The position of the two part-regions is changed, as a result of which the magnetization in the examination area changes, and real measured values which depend on the change in magnetization are recorded. A dependence distribution which depends on a spatial distribution of magnetic particles is then determined such that a sum which comprises as summands a) the difference of the real measured values from fictitious measured values which are determined by applying a transfer function to the dependence distribution, and b) the product of a regularization parameter and of a regularization value which is determined by applying the regularization functional to the dependence distribution, is minimized.

Abstract: The increasing cone angle of current high-end and future CT systems leads to a decrease in image quality if approximate cone-beam reconstruction methods are used. According to an exemplary embodiment of the present invention, an iterative four-dimensional cardiac CT reconstruction is provided, in which phase volumes are selected from the four-dimensional data set, each having the same spatial volume at different phase points. Corresponding voxels inside these phase volumes are then forward projected onto the same projection. After calculation of a different projection, these voxels are updated. This may provide for an efficient implementation of an iterative four-dimensional cardiac cone-beam CT reconstruction.

Abstract: A radiographic imaging apparatus includes a radiation detector (16) and a radiation source (12) which projects a non-parallel beam of radiation into field of view (14). A footprint of each voxel (v) which is projected on the detector (16) is corrected based on the position of the voxel (v) in the field of view (14) in relation to the radiation detector (16) and the radiation source (12). The contributions from substantially parallel redundant projections are further combined based on a fractional distance frac from a center point (82) of the voxel (v) to a center of each of the adjacent redundant projections.

Abstract: The invention relates to a method of imaging an interior of a turbid medium, a device for imaging an interior of a turbid medium, and a medical image acquisition device. A turbid medium is accommodated in a receiving volume (5), light from a light source is coupled into (10) and out of the receiving volume and detected (15) after which a dataset is obtained from the detected light (20). The dataset is then communicated to an image reconstruction algorithm (30) and an image of an interior of the turbid medium is reconstructed based on the detected light (35). According to the invention the dataset is changed prior to communicating the dataset to the image reconstruction algorithm into a further dataset (25), with a further dataset satisfying an input assumption underlying the image reconstruction algorithm.

Abstract: The invention relates to a system, a medical image acquisition system, and a method for imaging an interior of a turbid medium (25). The invention also relates to a marker (60) for use in the method for imaging an interior of a turbid medium (25). The system, the medical image acquisition system, and the method may be used for obtaining an image of an interior of a turbid medium (25) by: accommodation of a turbid medium (25) inside a receiving volume (20); irradiation of the receiving volume (20) with light from a light source; detection of light emanating from the receiving volume (20) as a result of irradiating the receiving volume (20) with light from the light source through the use of a photodetector unit. The detected light is then used to reconstruct an image of an interior of the turbid medium (25).

Abstract: An imaging system for imaging of a turbid medium comprises a radiation source to illuminate an object to be imaged. A detection system detects radiation from the object and includes a separation module which distinguishes radiation components having respective wavelength ranges. An analysis module forms a comparison of respective radiation components. An image dataset is reconstructed on the basis of the comparison of respective radiation components. The comparison e.g. involves (i) the ratio of the levels of the high-wavelength radiation component to the low-wavelength radiation component, or (ii) i the relative difference of the levels of high-wavelength radiation component to the detected radiation, or (iiii) the relative difference of the levels of the high-wavelength radiation component to the low-wavelength radiation component.

Abstract: A device for determining a concentration-related quantity of a fluorescent contrast agent applied to an object (2), in particular a turbid medium. Said device generally comprises a source (4) of electromagnetic radiation for irradiating the object (2) at an excitation wavelength and at least one first detecting means (6, 7.1, 7.2, . . . , 8) for detecting fluorescent electromagnetic radiation emitted by the contrast agent at a fluorescence wavelength, said first detecting means producing fluorescence intensity data (F). The proposed device further comprises at least one second detecting means (6, 7.1, 7.2, . . .

Abstract: Using only projection data in one temporal gating window around a certain target phase point may lead to motion artifacts such as blurred images. By using projection data corresponding to three temporal gating windows, which are slightly shifted with respect to each other but at least partially overlap, motion within the gating window may be estimated and, according to an exemplary embodiment of the present invention, this estimation may be used for improving the image quality. Advantageously, only the projection data inside the at least partially overlapping gating windows are used for reconstruction and motion compensation.

Abstract: The invention relates to an arrangement and a method for determining the spatial distribution of magnetic particles in an examination area. Magnetic field means are used to generate a spatially inhomogeneous gradient magnetic field with at least one region with a low field strength, in which the magnetization of the particles is in a state of non- saturation, whereas they are in a state of saturation in the remaining region. By using change means to shift the area with a low field strength within the examination area, a change in the magnetization of the magnetic particles is brought about which can be detected from outside by detection means and contains information about the spatial distribution of the magnetic particles in the examination area. The magnetic field means or the change means or the detection means or a combination of these means are arranged at least partially on a medical instrument.

Abstract: The invention relates to a device for imaging an interior of a turbid medium comprising: a) a receiving volume for receiving at least a part of the turbid medium, with the receiving volume being bound by a boundary having an opening bound by a brim, b) a light source for irradiating the turbid medium, and c) a photodetector unit for detecting light emanating from the volume as a result of irradiating the turbid medium. The device is adapted such that the brim is arranged for optically coupling the light source to the turbid medium and the turbid medium to the photodetector unit. One embodiment of the invention relates to a device for imaging an interior of a female breast comprising a cup-like receptacle (20) for accommodating the breast. The receptacle (20) comprises a convex shaped brim (60) arranged for optically coupling the light source to the patient's (55) breast and the breast to the photodetector unit.

Abstract: The invention relates to an imaging method, in which a projection data record of an examination area to be reconstructed is generated by acquiring projections from different projection directions, in particular with the aid of a computer tomograph. For each projection direction, a filter operator is determined that is optimally adapted to a projection geometry allocated to the respective projection direction. An image of the examination area is reconstructed from the projection data record by filtering the projections with the filter operators determined and by back projection of these filtered projections.

Abstract: The invention relates to a method of determining a spatial distribution of magnetic particles in an examination zone, in which a magnetic field is generated that has a first sub-zone of lower magnetic field strength and a second sub-zone of higher magnetic field strength. The positions of the two sub-zones are changed, as a result of which the magnetization in the examination zone changes. Measured values that depend on the change in magnetization are acquired. A reference response function by means of which measured values can be determined mathematically from a spatial distribution of magnetic particles is then determined by means of at least extensive magnetic specimen distribution. Finally, the spatial distribution of magnetic particles is reconstructed from the measured values by means of the reference response function.

Abstract: The invention relates to a method of determining a spatial distribution of magnetic particles in an examination area, in which a magnetic field is generated which has a first part-region having a relatively low magnetic field strength and a second part-region having a relatively high magnetic field strength. The position of the two part-regions is changed, as a result of which the magnetization in the examination area changes, and real measured values which depend on the change in magnetization are recorded. A dependence distribution which depends on a spatial distribution of magnetic particles is then determined such that a sum which comprises as summands a) the difference of the real measured values from fictitious measured values which are determined by applying a transfer function to the dependence distribution, and b) the product of a regularization parameter and of a regularization value which is determined by applying the regularization functional to the dependence distribution, is minimized.

Abstract: A radiographic imaging apparatus includes a radiation detector (16) and a radiation source (12) which projects a non-parallel beam of radiation into field of view (14). A footprint of each voxel (v) which is projected on the detector (16) is corrected based on the position of the voxel (v) in the field of view (14) in relation to the radiation detector (16) and the radiation source (12). The contributions from substantially parallel redundant projections are further combined based on a fractional distance frac from a center point (82) of the voxel (v) to a center of each of the adjacent redundant projections.

Abstract: The invention relates to an imaging method, especially a computerized tomography method, with which an object is penetrated by rays from different directions and measured values, which depend upon the intensity of the rays after penetrating the object, are acquired by a detector unit. From these measured values, an object image is reconstructed by means of back projection of measured-value-dependent back projection values. Therein, the object image is divided into overlapping, quasi-spherically symmetric image segments, each being defined by an image value and a quasi-spherically symmetric base function.

Abstract: The invention relates to a device for imaging an interior of a turbid medium and a medical image acquisition device comprising: a) a measurement volume (15) for accommodating the turbid medium (45); b) a light source (5) for irradiating the turbid medium (45); c) a photodetector unit 10 for detecting light emanating from the measurement volume (15). The device for imaging an interior of the turbid medium and the medical image acquisition device are adapted such that the devices further comprise a calibration device (55, 60) arranged to be optically coupled to the measurement volume (15) and comprising a calibration light source (65) arranged to simultaneously generate the excitation light and further light corresponding to the fluorescence light.

Abstract: It is an object of the invention to provide spiral computer tomography which has a high image quality. It relates to a reconstruction method for computer tomography of the heart, wherein the image is reconstructed from a data component of recordings of a partial detector path of a detector device and from a data component of recordings of a full detector path of the detector device, and to a computer tomograph having a beam source, a drive arrangement for driving the beam source in a spiral path around an object, a detector device for recording the radiation from the beam source which passes at least partially through the object, and a control device for reconstructing data components of a partial detector path and a full detector path.

Abstract: The present invention relates to a device for imaging a turbid medium (130, 132; 184) comprising: means (110; 134, 138, 140, 142, 144, 146) for optically scanning a predefined maximum area of a scanning plane (102; 104) for acquisition of imaging data, means (134, 136; 206, 208, 210) for detection of an outer contour of the turbid medium, means (112, 120, 122) for controlling the optical scanning such that a sub-area of the maximum area is scanned that is smaller than the maximum area and that covers the outer contour.

Abstract: A computed tomography scanner includes a first (20) and a second (21) detector. The second detector (21) has a relatively higher spatial resolution and a relatively smaller field of view (204) than that of the first detector (20). Projection data generated by the detectors (20, 21) is combined and reconstructed so as to generate relatively high resolution volumetric data (318) indicative of a region of interest (314) in an object under examination.

Abstract: The invention relates to an imaging method, especially a computerized tomography method, with which an object is penetrated by rays from different directions and measured values, which depend upon the intensity of the rays after penetrating the object, are acquired by a detector unit. From these measured values, an object image is reconstructed by means of back projection of measured-value-dependent back projection values. Therein, the object image is divided into overlapping, quasi-spherically symmetric image segments, each being defined by an image value and a quasi-spherically symmetric base function.