Abstract: The present invention is a method of and system for imaging an object with an ultrasound transducer array that transmits ultrasound beams and detects echoes reflected from the object. A plurality of adjacent ultrasound beams are transmitted at the object, each of the beams being separated from an adjacent beam by a first predetermined distance. A plurality of groups of echoes are received from the object, with each of the groups of echoes corresponding to one of the plurality of the ultrasound beams. Each of these echoes are spaced from the corresponding ultrasound beam by a second predetermined distance which is less than the first predetermined distance. The transmitted ultrasound beams are arranged such that one of the received echoes corresponding to an ultrasound beam substantially overlaps with one of the received echoes corresponding to an adjacent ultrasound beam. At least a subset of the received echoes are then processed to obtain B-mode data from each of the processed echoes.

Abstract: Spatially compounded images are produced by combining signals from different look directions as a function of the received echo signals. In one embodiment the combinational processing of the echo signals is a function of the steering direction sensitivity of the echo signals. Adaptive variation in the combinational processing can be done on a pixel-by-pixel basis within a particular image, on an image-by-image basis, or in response to the diagnostic exam being performed.

Abstract: An ultrasonic probe is moved to scan a volumetric region of the body. As it is moved, targets within the region are interrogated from multiple look directions. The echo data from the multiple look directions are compounded to form spatially compounded image data, which is processed for display in a three dimensional display format.

Abstract: An ultrasonic diagnostic imaging system receives echo signals from a transducer for digital processing and image formation. An analog to digital converter converts the analog echo signals to digital signal samples. The dynamic range of the analog to digital converter is more efficiently used for harmonic imaging and saturation of the analog to digital converter is more effectively prevented by attenuating the fundamental signal content of echo signals prior to analog to digital conversion.

Abstract: An ultrasonic diagnostic imaging system and method are described for performing fundamental frequency and second harmonic frequency imaging simultaneously. Transmit bursts are employed which include a first waveform component optimized for fundamental imaging and a second waveform component optimized for harmonic imaging. The first waveform component may be centered in the transducer passband, and the second waveform component may be located on the opposite side of the center of the transducer passband from its second harmonic frequency, for instance. Echoes received from the bursts are separated into fundamental and harmonic components and used to form separate fundamental and harmonic images or blended fundamental/harmonic images.

Abstract: An ultrasonic diagnostic imaging system receives fundamental frequency, harmonic contrast, and tissue harmonic echo information for image processing. The fundamental and harmonic signal content of the echo information is analyzed and the relative content of an output signal is adjusted as necessary to take advantage of the different characteristics of the different types of echo information present in the echo signal. The ultrasound system can produce images which are an adaptive blend of fundamental, tissue harmonic and harmonic contrast echo information.

Abstract: Ultrasonic imaging apparatus and method are described for reducing the flash artifact in ultrasonic harmonic images. Harmonic signals are separated by pulse inversion separation which uses multiple transmit pulses which may be subject to motion artifacts. The motion artifacts are detected and subtracted from the harmonic signals to produce harmonic images with reduced flash artifacts. The motion artifacts may also be reduced by notch filtering. In another embodiment the amount of motion in the image is detected and the flash artifact is reduced in accordance with the detected motion. The amount of artifact signal which is removed is variable in accordance with anticipated image motion or clinical application.

Abstract: An ultrasonic diagnostic imaging system and method are described for performing fundamental frequency and second harmonic frequency imaging simultaneously. Transmit bursts are employed which include a first waveform component optimized for fundamental imaging and a second waveform component optimized for harmonic imaging. The first waveform component may be centered in the transducer passband, and the second waveform component may be located on the opposite side of the center of the transducer passband from its second harmonic frequency, for instance. Echoes received from the bursts are separated into fundamental and harmonic components and used to form separate fundamental and harmonic images or blended fundamental/harmonic images.

Abstract: A method and apparatus are described which produce spatially compounded panoramic ultrasonic images by electronically steering beams in a plurality of different look directions as a transducer is moved in relation to a panoramic image field. The received echo information is compounded, then aligned and combined with previously acquired echo information to form a spatially compounded panoramic image. Alternatively, the received echo information may be aligned with previously acquired echo information, then combined to produce spatial compounding and a panoramic image in one process.

Abstract: An ultrasonic diagnostic imaging system is used to produce spatially compounded ultrasonic images with beams transmitted in multiple look directions from a curved array scanhead. The beam steering is a function of both the curvature of the curved array and electronic beam steering. The beams may be steered in groups of parallel beams, or in groups which have a common angular orientation to their points of origin along the array. The describe embodiments provide advantages in beamforming and registration coefficient usage, sampling uniformity, speckle reduction uniformity, and a larger area of maximum compounding effect.

Abstract: An ultrasonic diagnostic imaging system is are described in which the component ultrasonic images which are to be spatially compounded are corrected for misregistration prior to compounding. The component images may be registered to a reference image or registered to form intermediate compound images which are then registered and compounded. The misregistration may be sensed by calculating a similarity or difference metric for a region of interest of the image frames being registered, or on the basis of reference lines acquired for the purpose of registering images.

Abstract: Spatially compounded images are produced by combining signals from different look directions as a function of the received echo signals. In one embodiment the combinational processing of the echo signals is a function of the steering direction sensitivity of the echo signals. Adaptive variation in the combinational processing can be done on a pixel-by-pixel basis within a particular image, on an image-by-image basis, or in response to the diagnostic exam being performed.

Abstract: An ultrasonic diagnostic imaging system produces spatially compounded images by combining component frames acquired from different look directions. Different regions of the spatially compounded images are formed by different numbers of overlapping component frames. Seam artifacts at the boundaries of the regions are reduced by processing the component frames to maintain a common signal and noise characteristic, varying the transmit pulse amplitude or the receiver gain, spatially aligning component frames at the boundaries, or weighting scan lines less heavily at the seam boundaries.

Abstract: An ultrasonic diagnostic imaging system and method are described in which the number of acquired ultrasonic images which are compounded to form a spatially compounded image is variable. The number of acquired images which is compounded is varied in response to changes in system operating parameters initiated directly or indirectly by the system user.

Abstract: An ultrasonic diagnostic imaging system produces spatially compounded images by combining component frames acquired from different look directions. The component frames are acquired in estimate space, converted to sampled data in a common coordinate system and compounded. Conversion to the common coordinate system is performed by modulating the sampling to the desired coordinate system or by resampling of the image data. The estimate data of the spatially compounded image is then scan converted to a display data format for display of the spatially compounded image.

Abstract: An adaptive ultrasonic spatial compounding method is described in which the number of component ultrasonic images which are to be spatially compounded is varied in response to the type of scanning procedure. In a survey mode, when the transducer is rapidly scanning a patient and there is a low degree of correlation from frame to frame, the number of component ultrasonic images which are compounded is reduced. In a study mode, when the transducer is held relatively stationary to study a particular region of the body and the frame-to-frame spatial correspondence is relatively high, the number of component images is increased.

Abstract: An ultrasonic diagnostic imaging system produces spatially compounded images by combining component frames acquired from different look directions. In a first embodiment, the oldest component frame used to form a spatially compounded image is subtracted from the spatially compounded image to produce a partially summed image, and a newly acquired frame is added to the partially summed image to form a new spatially compounded image. In a second embodiment, different groups of component frames are concurrently summed to form multiple spatially compounded images simultaneously. The display alternates between the display of the simultaneously produced spatially compounded images.

Abstract: An ultrasonic imaging method is described in which component ultrasonic images which are to be spatially compounded are corrected for misregistration prior to compounding. The component images may be registered to a reference image or registered to form intermediate compound images which are then registered and compounded. The misregistration may be sensed by calculating a similarity or difference metric for a region of interest of the image frames being registered, or on the basis of reference lines acquired for the purpose of registering images.

Abstract: An ultrasonic diagnostic imaging system is provided which aid in the diagnosis of patient conditions by providing access from the ultrasound system to a library of reference ultrasonic images. The image library is cataloged in accordance with an image characteristic such as the type of examination, the part of the body or the type of pathology shown in the image, and the images of the library are accessed in accordance with these characteristics. The image library may be remotely located and accessible by a number of ultrasound systems over a network, or it may be located on the ultrasound system itself such as on a system disk drive. In a preferred embodiment reference images are concurrently displayed with patient images to aid in discerning the patient's condition.