摘要:
A rapid, non-invasive realtime modality for detecting differential backscatter in ultrasound is achieved using narrowband interrogating frequencies to maximize signal-to-noise ratio and to minimize location errors. Additional improvement in signal-to-noise ratio and separation of tissue populations are achieved by cyclically alternating through a fixed number of predetermined burst lengths and by employing multiple narrowband bursts of differing fundamental frequencies.
摘要:
A method and apparatus are described for testing the integrity of an ultrasonic transducer probe or the ultrasound system connected to the probe. The elements of the transducer are pulsed at a time when the probe is not in contact with a patient and the surface of the probe lens is exposed to the open air. The channel electronics receives the echo signal returned from the lens-air interface and reverberations between this interface and the transducer. These signals are analyzed by a diagnostic processor coupled to the channel electronics for characteristics such as amplitude, time of echo reception, group delay, and other characteristics to determine the possible existence of problems such as faulty transducer elements or connections and problems in the system receive electronics. The diagnostic processor can adaptively adjust an operating characteristic of the system electronics such as gain or time delay to compensate for a detected out of tolerance condition.
摘要:
An image processing system and method visually documents and displays changes between historical and later mammographic images, preferably in three dimensions. A composite image is created which visually emphasizes temporal differences between the historical and later images. Preferably three-dimensional, digitized images, displayable in various projections, are stored for archival purposes on computer readable media. An image processor preferably exploits an optical correlator to register the historical and later images accurately and provide correlation values as temporal scalars of the differences. The registered images are then compared, voxel-by-voxel, to detect temporal differences. The composite image is displayed with synthetic colors or other visual clues to emphasize apparent changes (for example, tumor growth or shrinkage).
摘要:
Ultrasonographic imaging of small calcifications or similar hard bodies distributed in human breast tissue is enhanced by correlating an ultrasonographic data set with a radiographic image of the same region of interest. A “constellation” or cluster of small calcifications is distinguished from speckle noise by the cross-correlation, which is quite sensitive to the coincidence of a pattern of distributed small targets in both the ultrasonographic and radiographic images, notwithstanding the presence of random noise. An optical correlator is preferably used to perform high speed cross-correlations. The three-dimensional position of an individual calcification is preferably found by projecting from an identified point in the radiographic image, along a projection vector, to a voxel with extreme density in the ultrasonographic volumetric data set. Multiple projection vector orientations are tested for image correlation, to accomodate any probable skew between the ultrasonographic and radiographic projections.
摘要:
Ultrasonographic information about the internal structure of a subject body is combined with x-ray or other radiographic information from the same subject body by using an optical correlator to quickly find a transformation which aligns the information from both sources, even if they are acquired in different coordinate systems. Various spatial transformations are applied to the information and cross-correlations are quickly performed. The transformation which gives the best cross-correlation is used to align the two data sets, which can then be displayed visually. The resulting display can be used as an aid in medical diagnosis, for example in diagnosing suspected malignant lesions in a woman's breast.
摘要:
A method of curing an anaerobic resin, which primarily contains acrylic resin, includes externally catalyzing the cure of the resin with a metal-beta keto ester complex having the structural formula: ##STR1## where M is a transition metal; R.sub.1 is selected from the group consisting of alkyl groups having from 1 to 20 carbon atoms, benzene, naphthalene, anthracene, and hydrocarbon substituted aromatic; R.sub.2 and R.sub.3 are selected from hydrogen, alkyl groups having from 1 to 20 carbon atoms, benzene, naphthalene, anthracene and hydrocarbon substituted aromatic; R.sub.4 is selected from alkyl groups having from 1 to 20 carbon atoms; and n is equal to the valence of the metal M.
摘要翻译:主要包含丙烯酸树脂的厌氧树脂的固化方法包括用具有以下结构式的金属-β酮酯复合物外部催化树脂的固化:其中M是过渡金属; R1选自具有1至20个碳原子的烷基,苯,萘,蒽和烃取代的芳族; R2和R3选自氢,具有1至20个碳原子的烷基,苯,萘,蒽和烃取代的芳族; R 4选自具有1至20个碳原子的烷基; 并且n等于金属M的化合价。