Steered continuous wave doppler methods and systems for two-dimensional ultrasound transducer arrays
Methods and systems for acquiring spectral and velocity information with a multi-dimensional array are provided. For example, a dedicated receive aperture is formed at a multi-dimensional array for steered continuous wave imaging. Other elements not within the dedicated receive aperture are used for transmitting continuous waves or transmitting and receiving pulsed waveforms in other modes of imaging. As another example, switches or other structures are provided for selecting between a plurality of possible apertures for a steered continuous wave aperture. The selection is performed in response to a configuration of an ultrasound system, such as selection of a focal location or steer direction. The aperture is then used for either transmit or receive operations of steered continuous wave imaging. As yet another example, at least part of the steered continuous wave beamformer is provided within a transducer assembly. The transducer assembly includes a probe housing and a connector housing electrically connected by a cable. In yet another example, at least one angle of a three-dimensional indication of flow direction is input from a user. Velocity values in either steered continuous wave imaging or pulsed wave imaging are corrected as a function of a three-dimensional indication of flow direction.
1. A method for acquiring spectral information with a multi-dimensional array, the method comprising:
(a) transmitting continuous waves from the multi-dimensional array;
(b) receiving signals responsive to (a) at a dedicated steered continuous wave receive aperture of the multi-dimensional array;
(c) transmitting pulsed waves with elements comprising the multi-dimensional array separate from the elements comprising the dedicated steered continuous wave receive aperture; and
(d) receiving signals responsive to (c) with elements comprising the multi-dimensional array separate from the elements comprising the dedicated steered continuous wave receive aperture.
2. The method of claim 1 wherein the dedicated steered continuous wave receive aperture is symmetric about a center of the multi-dimensional transducer array.
3. The method of claim 1 wherein the multi-dimensional transducer array comprises an array on one of a rectangular, triangular, hexagonal and square grid, the dedicated steered continuous wave receive aperture comprises elements in the outer corners of the multi-dimensional transducer array.
4. The method of claim 1 further comprising:
(e) shielding at least one of: pre-amplifiers, cables, receive beamformer circuits and combinations thereof within a transducer probe assembly of the dedicated steered continuous wave receive aperture from other devices.
5. The method of claim 1 further comprising:
(e) transmitting the signals received during (b) to a dedicated continuous wave beamformer over a path separate from signals received during (d).
6. The method of claim 1 wherein elements of the dedicated steered continuous wave receive aperture have a larger pitch than the elements of the multi-dimensional array separate from the elements of the dedicated steered continuous wave receive aperture.