摘要:
A projectional densitometry system performs a scan of an individual's left and right femora by using the location of one femur to estimate a starting location for scanning the opposite femur. The estimated starting location of the second femur scan is based on metric data inputted by the operator or extracted from the first femur scan. Alternatively, the densitometry system performs an initial bone-locating scan of both femora, after which it performs a second, density-measuring scan based on the metric data extracted from the initial scan. A special leg positioning device is used to properly orient both femora for scanning, obviating the need to reposition the individual after scanning the first femur.
摘要:
A method for automatically analyzing the morphometry of bone (20, 21) from data obtained by lateral digital scans of the bone (20, 21) obtains a matrix of data values assembled from an x-ray scan. The matrix is analyzed to locate an axis of the bone from which subsequent measures may be referenced. Once the axis is fixed, one or more of several useful indicia of bone condition such as length or interbone spacing can be calculated.
摘要:
A dual energy densitometer (10) includes a solid state linear x-ray detector (13) which may be swept across the patient with the movement of a poly-energetic fan beam (23) of x-rays to produce a digital bone density image. A broad spectrum film plate (25) interposed between the detector (13) and the patient simultaneously provides a full spectrum radiographic image of high resolution and low parallax such as may be used for morphometric studies. Intervertebral spaces (40) may be used to measure vertebrate heights which may be statistically combined to provide a standard against which crush fractures may be detected.
摘要:
An ultrasonic densitometer for measuring physical properties and integrity of a skeletal member in vivo has at least one transducer (21) and electrical means for launching an ultrasound pulse, detecting receipt of the pulse and determining a parameter therefrom. The densitometer may determine transit time through the member and compare with a database value, or may determine absolute attenuation at one or more frequencies and perform a comparison based on attenuation.
摘要:
L'invention décrit un densitomètre à ultrasons (100) dans lequel des transducteurs ultrasoniques (121) sont placés en position éloignée les uns des autres dans un bain d'eau (103) dans lequel on introduit le talon d'une personne. Il est possible de mesurer le temps de transit d'une impulsion ultrasonique à travers l'eau et le talon, ainsi que l'atténuation de l'impulsion pour évaluer les propriétés physiques de l'os du talon. Une unité de commande centrale (38, 160, 162) coordonne la mesure ultrasonique avec le remplissage et la vidange automatique du bain d'eau, afin de permettre une opération hygiénique et répétitive. L'eau peut être préchauffée pour améliorer le confort du patient, ainsi que la fiabilité du résultat. Le temps de préchauffage est réduit par le fait que l'eau est préchauffée dans une chambre de préremplissage séparée (132) pendant l'examen précédent. L'alimentation par gravité de l'eau réduit la complexité de sa manipulation et permet un fonctionnement extrêmement silencieux. Un ergot (110) situé dans le bain d'eau et s'adaptant entre les orteils du patient, ainsi qu'un support de mollet (120) contribuent à limiter les mouvements du patient pendant la mesure.
摘要:
An ultrasound densitometer (10) for measuring the physical properties and integrity of a member in vivo includes a transmit transducer (21) from which acoustic signals are transmitted, and a receive transducer (21) which receives the acoustic signals after they have been transmitted through the member (32) and/or a material with known acoustic properties. The densitometer allows the physical properties of a member to be measured without having to determine the distance between the transducers. The densitometer is able to measure the physical properties and integrity of the member from the transit time of acoustic signals through the member and/or by determining the absolute attenuation of at least one specific frequency component of acoustic signals transmitted through the member.
摘要:
An acoustic array of independently sensitive detecting elements is produced by locating a pattern of electrodes on a piezoelectric polymer film. Sensitivity of the film and a spaced away supporting structure are used to reduce artifacts caused by acoustic reflection in the supporting structure.