Abstract: A transducer array is connected with a catheter housing. As the transducer array is rotated, the catheter housing also rotates. As a result, at least a portion of the catheter housing twists about a longitudinal axis. By applying rotation in a controlled way, such as with a motor, a plurality of two-dimensional images for three-dimensional reconstruction may be obtained. The rotation of the catheter housing may limit the total amount of rotation of the array, such as rotating the array through a 90 degree or less amount of rotation about the longitudinal axis. The housing of the catheter is formed with a soft section. The softer material allows for a greater amount or increased ease for twisting the catheter.

Abstract: Synthetic transmit aperture is provided for three-dimensional ultrasound imaging. A transducer may have separate transmit and receive elements. Broad beams are transmitted, allowing fewer transmit elements and/or more rapid scanning. A multidimensional receive array generates data in response to sequential transmissions, such as transmissions from different angles. The data is combined to increase resolution. A transducer array with offset transmit elements for forming a transmit line source may be used.

Abstract: A foldable transducer array is unfolded or deployed for use, providing a larger radiating surface. While folded, the transducer array has a smaller width or volume for insertion into and withdrawal from the patient.

Abstract: CMUT elements are formed on a substrate. Electrical conductors are formed to interconnect between different portions of the substrate. The substrate is then separated into pieces while maintaining the electrical connections across the separation. Since the conductors are flexible, the separated substrate slabs may be positioned on a curved surface while maintaining the electrical interconnection between the slabs. Large curvatures may be provided, such as associated with forming a multidimensional transducer array for use in a catheter. The electrical interconnections between the different slabs and elements may allow for a walking aperture arrangement for three dimensional imaging.

Abstract: A transducer array is connected with a catheter housing. As the transducer array is rotated, the catheter housing also rotates. As a result, at least a portion of the catheter housing twists about a longitudinal axis. By applying rotation in a controlled way, such as with a motor, a plurality of two-dimensional images for three-dimensional reconstruction may be obtained. The rotation of the catheter housing may limit the total amount of rotation of the array, such as rotating the array through a 90 degree or less amount of rotation about the longitudinal axis. The housing of the catheter is formed with a soft section. The softer material allows for a greater amount or increased ease for twisting the catheter.

Abstract: A multi-dimensional, such as a two-dimensional, array is provided within a transesophageal probe housing. Since the size of the transesophageal probe housing is limited for comfort of a patient, active electronics are positioned spaced away from the multi-dimensional transducer array, such as within a handle of the transesophageal probe housing. Signal conductors connect the multi-dimensional transducer array to the active electronics. The elements of the multi-dimensional transducer array have a capacitance much lower than parasitic capacitance of the connecting cables. To provide a higher signal-to-noise ratio, the elements are formed from multiple layers of transducer material, increasing the capacitance of each element.

Abstract: Electrical connection is provided in a transducer stack through a backing block. A flexible circuit is sandwiched between pieces of acoustic attenuating material. For example, 2 to 200 or more flexible circuits are stacked in alternating layers with pieces of acoustically attenuating material. The alternating layers are then connected together to form a backing block with Z-axis electrical connection. The top surface of the connected backing block includes a plurality of exposed electrical traces from the flex circuit. Since flex circuits are used, the electrical traces are precisely aligned along one dimension. Since pre-formed acoustic attenuating material pieces are used, precise alignment is provided along a second or orthogonal dimension. The substrate holding the electrical traces in the flexible circuits provides more stability and allows for easier connection to circuit boards as compared to individual strips of metal.

Abstract: Matching layers are provided, including: electrically conductive acoustic matching layers, methods for conducting electric current through matching layers, methods for manufacturing multi-dimensional arrays using conductive matching layers, and multi-dimensional arrays with electrically conducting matching layers. Matching layers with conductors aligned for providing electrical conduction through the thickness or range dimension of the matching layer are provided. For example, vias, aligned magnetic particles, or conductive films at least partially or entirely within the matching layer of each element allow electrical conduction from the transducer material to a ground foil or flex circuit. By using multiple electrical conductive matching layers, a gradation in acoustic impedance for better matching is provided while allowing dicing of the entire stack, including the matching layers and the electroceramic material, in one step.