Abstract: A method and system for using in a two-modality apparatus. The two-modality apparatus comprises a couch with a table top, a first modality unit and a second modality unit. A second image of a target portion of an object when the table top is at a second working position of the second modality unit may be acquired. A second sag of the table top at a second measurement point of the table top according to the second image may be determined based on the image. A difference between a first sag of the table top at a first measurement point of the table top and the second sag may be estimated based on the second sag and standard data. The standard data provides a relationship relating to a sag of the table top positioned between the first modality unit and second modality unit.

Abstract: A method and system for using in a two-modality apparatus. The two-modality apparatus comprises a couch with a table top, a first modality unit and a second modality unit. A second image of a target portion of an object when the table top is at a second working position of the second modality unit may be acquired. A second sag of the table top at a second measurement point of the table top according to the second image may be determined based on the image. A difference between a first sag of the table top at a first measurement point of the table top and the second sag may be estimated based on the second sag and standard data. The standard data provides a relationship relating to a sag of the table top positioned between the first modality unit and second modality unit.

Abstract: An apparatus and method for noninvasively measuring intracranial pressure of a subject using an ultrasound transducer. The transducer is used to measure arterial wall movement of an intracranial segment and an extracranial segment of the subject's ophthalmic artery as different external pressure forces are applied to the orbital area of the subject. When the waveforms of arterial wall movement between the intracranial segment and the extracranial segment are similar the intracranial pressure can be determined.

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: 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: 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: Some aspects include acquisition of a first plurality of projection images of a volume using a megavoltage x-ray source, each of the first plurality of projection images associated with a respective one of a first plurality of locations of the megavoltage x-ray source, acquisition of a second plurality of projection images of the volume using a kilovoltage x-ray source, each of the second plurality of projection images associated with a respective one of a second plurality of locations of the kilovoltage x-ray source, and performance of digital tomosynthesis reconstruction to generate a three-dimensional image of the volume based on the first plurality of projection images and the second plurality of projection images. The first axis may be perpendicular to the second axis.

Abstract: A system and method for tomosynthesis, the method including emitting a respective imaging x-ray from each of a plurality of imaging x-ray sources disposed in a fixed relation with respect to one another, acquiring x-ray absorption projections of an object, each of the x-ray absorption projections associated with an imaging x-ray emitted by a respective one of the plurality of imaging x-ray sources, and performing digital tomosynthesis using the x-ray absorption projections to generate a cross-sectional image of the object.

Abstract: Some aspects include acquisition of a first plurality of projection images of a volume using a megavoltage x-ray source, each of the first plurality of projection images associated with a respective one of a first plurality of locations of the megavoltage x-ray source, acquisition of a second plurality of projection images of the volume using a kilovoltage x-ray source, each of the second plurality of projection images associated with a respective one of a second plurality of locations of the kilovoltage x-ray source, and performance of digital tomosynthesis reconstruction to generate a three-dimensional image of the volume based on the first plurality of projection images and the second plurality of projection images. The first axis may be perpendicular to the second axis.

Abstract: Some aspects include acquisition of a first plurality of projection images of a volume using a megavoltage x-ray source, each of the first plurality of projection images associated with a respective one of a first plurality of locations of the megavoltage x-ray source, acquisition of a second plurality of projection images of the volume using a kilovoltage x-ray source, each of the second plurality of projection images associated with a respective one of a second plurality of locations of the kilovoltage x-ray source, and performance of digital tomosynthesis reconstruction to generate a three-dimensional image of the volume based on the first plurality of projection images and the second plurality of projection images. The first axis may be perpendicular to the second axis.

Abstract: The present invention is a method and system for computed tomography imaging. The system for computed tomography imaging may comprise: a) an x-ray source; b) an x-ray detector; and c) a processing unit, wherein the processing unit is configured to carry out the steps: i) obtaining CT projections of an object, the projections comprising at least one truncated projection; ii) calculating material-equivalent thickness (MET) values for the truncated projection; iii) establishing parameterized point-pairs separated in distance by the MET values; iv) fitting the parameterized point-pairs to a parameterized curve or to a set of curves according to a set of constraints on spatial relationships between the point-pairs; v) completing the truncated projections; and vi) reconstructing a CT image from non-truncated projections and the completed truncated projections.

Abstract: Some aspects include acquisition of a first plurality of projection images of a volume using a megavoltage x-ray source, each of the first plurality of projection images associated with a respective one of a first plurality of locations of the megavoltage x-ray source, acquisition of a second plurality of projection images of the volume using a kilovoltage x-ray source, each of the second plurality of projection images associated with a respective one of a second plurality of locations of the kilovoltage x-ray source, and performance of digital tomosynthesis reconstruction to generate a three-dimensional image of the volume based on the first plurality of projection images and the second plurality of projection images. The first axis may be perpendicular to the second axis.

Abstract: A system includes movement of a treatment delivering x-ray source to a treatment position, creation of projection images of a target using an imaging x-ray source while the treatment delivering x-ray source is disposed at the treatment position, and performance of digital tomosynthesis on the projection images while the treatment delivering x-ray source is disposed at the treatment position to generate a cross-sectional image of the target. A characteristic of an x-ray beam to be delivered by the treatment delivering x-ray source may be automatically modified based on the cross-sectional image. In some aspects, the imaging x-ray source translates in a plane normal to a beam axis of the treatment delivering x-ray source at the treatment position, and pivots about an axis passing through the imaging x-ray source during creation of projection images.

Abstract: The present invention is a method and system for computed tomography imaging. A method for computed tomography imaging may comprise: a) obtaining CT projections of an object, the projections comprising at least one truncated projection; b) calculating material-equivalent thickness (MET) values for the truncated projection; c) establishing parameterized point-pairs separated in distance by the MET values; d) fitting the parameterized point-pairs to a parameterized curve or to a set of curves according to a set of constraints on spatial relationships between the point-pairs; e) completing the truncated projections; and f) reconstructing a CT image from non-truncated projections and the completed truncated projections.

Abstract: A system includes movement of a treatment delivering x-ray source to a treatment position, creation of projection images of a target using an imaging x-ray source while the treatment delivering x-ray source is disposed at the treatment position, and performance of digital tomosynthesis on the projection images while the treatment delivering x-ray source is disposed at the treatment position to generate a cross-sectional image of the target. A characteristic of an x-ray beam to be delivered by the treatment delivering x-ray source may be automatically modified based on the cross-sectional image. In some aspects, the imaging x-ray source translates in a plane normal to a beam axis of the treatment delivering x-ray source at the treatment position, and pivots about an axis passing through the imaging x-ray source during creation of projection images.

Abstract: A “relaxoscope” (100) detects the degree of arterial endothelial function. Impairment of arterial endothelial function is an early event in atherosclerosis and correlates with the major risk factors for cardiovascular disease. An artery (115), such as the brachial artery (BA) is measured for diameter before and after several minutes of either vasoconstriction or vasorelaxafion. The change in arterial diameter is a measure of flow-mediated vasomodification (FMVM). The relaxoscope induces an artificial pulse (128) at a superficial radial artery (115) via a linear actuator (120). An ultrasonic Doppler stethoscope (130) detects this pulse 10-20 cm proximal to the point of pulse induction (125). The delay between pulse application and detection provides the pulse transit time (PTT). By measuring PTT before (160) and after arterial diameter change (170), FMVM may be measured based on the changes in PTT caused by changes in vessel caliber, smooth muscle tone and wall thickness.