Hologic, Inc.

Noah Berger

Jay A Stein

Richard E Cabral

Howard P Weiss

Russell J Gershman

Eric Von Stetten

Tom Richardson

Thomas L Kelly

Donald Barry

Joel B Weinstein

Tracy L Ramsdell

Tina LeFebvre

Steven Teta

Dao-Yi Zhu

A method of calibrating an ultrasound bone analysis apparatus having a pair of transducer assemblies. Each transducer assembly has a transducer and a coupling pad, and is movable relative to the other so that a face of each pad can be moved to a position in which they mutually contact and to a position where the faces contact body parts. The method according to the present application includes transmitting an ultrasound signal from one transducer and receiving a signal corresponding to the transmitted ultrasound signal through the other transducer when the transducer assemblies are in the first position and the second position. A time for the ultrasound signal to pass through the body part is determined, and a width of the body part based on positions of the transducers is determined. Then, using the time and width values a speed of sound of the ultrasound signal passing through the body part with squish compensation is calculated.

X-ray bone densitometry

A whole body x-ray bone densitometry system includes a table extending parallel to a Y-axis of an XYZ coordinate system for supporting a patient at a patient position; an x-ray source for emitting a narrow angle fan beam of x-rays to irradiate at any one time a scan line which is transverse to the Y-axis and is substantially shorter than the width of a body cross-section of a typical adult patient occupying the patient position. An x-ray detector is aligned with the source along a source-detector axis which is transverse to the Y-axis, for receiving x-rays from the source within the angle of the fan beam after passage thereof through the patient position. The detector has a number of detecting elements arranged along a direction transverse to the Y-axis and to the source-detector axis. A source-detector support on which the source and detector are mounted at opposite sides of the patient position is coupled with a scanning mechanism moving at least one of the patient table and the source-detector support relative to the other to scan the patient position with the narrow angle fan beam in successive scans parallel to the Y-axis in which the source-detector axis is at different angles relative to the patient position as between different ones of successive scans, but in each of the successive scans, an origin of the fan beam in the source is at the same vertical distance from the patient table. The distance between the fan beam origin and the table may be selectively varied between scan passes, in order to vary scan pass magnification.

Whole-body x-ray bone densitometry using a narrow-angle fan beam,

Variations in x-ray beam, filtration and detector gain characteristics are corrected by a multiple thickness flattening system. Preferably, an automatic multi-position attenuator mechanism inserts into the x-ray beam one or more flat reference attenuators of uniform composition. Thereafter, the response at each detector channel is measured. Unique factors are thus collected for each channel at multiple attenuation levels. An overall uniform response across the scan field is achieved by applying these correction factors to subsequent scan data. The current system compensates for detector gain by alternately turning X-rays on and off, so that dark level measurements can be interspersed with X-ray signal measurements. Detector offsets are eliminated in a linear data representation, while beam and detector flattening corrections are applied in a logarithmic data representation.

X-ray densitometer detector calibration by beam flattening and

An x-ray bone densitometry system includes a table having a movable support surface configured to support a patient, an x-ray source and an x-ray detector positioned on opposite sides of said support surface so that a patient positioned on the support surface is between the x-ray source and the x-ray detector, the x-ray source and the x-ray detector being aligned in a fixed relationship relative to each other such that x-rays emitted from the source impinge the x-ray detector, the x-rays that impinge the detector producing dual energy scan data, a processor coupled to the x-ray source, the x-ray detector and the table and configured to actuate movement of said support surface, to receive the dual energy scan data, to extract from the dual energy scan data, dual energy image data and single energy image data, and to store the dual energy and the single energy image data in respective data records for selective display, and at least one display connected to the processor for displaying the dual energy and/or the single energy image data. Methods for displaying single energy and dual energy images on the display are also provided.

The system of the present invention uses x-rays having a narrow fan beam to scan patients for bone density and soft tissue body composition measurement and imaging. In addition to single pass scanning of body parts such as the spine, hip and forearm, a method for multiple pass whole body scanning is provided. The system includes a movable scan table configured to support a patient and a C-arm associated with the table. The C-arm is configured to support an x-ray source in opposite to an x-ray detector at opposite sides of the patient. A scanning mechanism is provided to move the scan table and C-arm to scan the patient with overlapping adjacent x-ray fan beams in successive scan passes along the length of the patient. A scan pass combination scheme that blends areas of overlap is employed to compensate errors related to height dependency. The blending is performed according to the height of the part of patient scanned in the overlap and the distance from the edge of the scan pass.

X-ray bone densitometry using multiple pass scanning with image blending

Best scan parametric values of a x-ray bone densitometry scanning system for a particular patient is selected according to a thickness of the patient. An operator initially selects scan parametric values of a fast mode scan which is the recommended default, and then commences the fast mode scan. At the initial portion of the scan, the x-ray thickness of the patient is measured. If the measured x-ray thickness is not greater than a predetermined limit of the fast mode scan, the fast mode scan is continued. If the measured x-ray thickness is greater than the predetermined limit of the fast mode scan, the x-rays are turned off, and the operator is given a choice of continuing with the fast mode scan or restarting with a slower mode scan. If the operator selection is to continue, the fast mode scan is continued. If the operator selects restarting, a slower mode scan is commenced.

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Waltham, MA, United States of America

Noah Berger