摘要:
A transducer backing material includes a sticky epoxy resin containing tungsten particles and silver particles. A method of applying a backing material to a transducer includes pouring a mixture of epoxy resin, tungsten particles, and silver particles into a mold containing a layer of piezoelectric material, degassing the mixture, and curing the mixture at a pressure of approximately one atmosphere until the mixture dries.
摘要:
A method of applying a matching layer to a transducer includes placing the transducer on a fixture and covering the transducer with a stencil so that an opening in the stencil allows access to a metal-coated, piezoelectric surface of the transducer, and so that the stencil is affixed to the transducer surface. A roughly cylindrically shaped bead of epoxy is extruded onto the stencil at a predetermined distance from the opening, and a blade is positioned upstanding relative to the transducer surface and located so that the bead lies between the blade and the opening. The fixture is moved laterally so that the blade rolls the bead across the exposed transducer surface to form a layer of epoxy thereon. The fixture can then be moved back in the opposite direction to its initial position if desired. The assembly can also be subjected to a vacuum before the fixture is returned to its initial position. If desired, the fixture can be designed to vibrate during movement. Also if desired, the epoxy bead can initially be placed in a trough designed to decrease surface-area exposure to the air. Alternatively, the fixture can be kept stationary while the blade is moved.
摘要:
A method of applying a matching layer to a transducer includes placing the transducer on a fixture and covering the transducer with a stencil so that an opening in the stencil allows access to a metal-coated, piezoelectric surface of the transducer, and so that the stencil is affixed to the transducer surface. A roughly cylindrically shaped bead of epoxy is extruded onto the stencil at a predetermined distance from the opening, and a blade is positioned upstanding relative to the transducer surface and located so that the bead lies between the blade and the opening. The fixture is moved laterally so that the blade rolls the bead across the exposed transducer surface to form a layer of epoxy thereon. The fixture can then be moved back in the opposite direction to its initial position if desired. The assembly can also be subjected to a vacuum before the fixture is returned to its initial position. If desired, the fixture can be designed to vibrate during movement. Also if desired, the epoxy bead can initially be placed in a trough designed to decrease surface-area exposure to the air. Alternatively, the fixture can be kept stationary while the blade is moved.
摘要:
A method of applying a matching layer to a transducer includes placing the transducer on a fixture and covering the transducer with a stencil so that an opening in the stencil allows access to a metal-coated, piezoelectric surface of the transducer, and so that the stencil is affixed to the transducer surface. A roughly cylindrically shaped bead of epoxy is extruded onto the stencil at a predetermined distance from the opening, and a blade is positioned upstanding relative to the transducer surface and located so that the bead lies between the blade and the opening. The fixture is moved laterally so that the blade rolls the bead across the exposed transducer surface to form a layer of epoxy thereon. The fixture can then be moved back in the opposite direction to its initial position if desired. The assembly can also be subjected to a vacuum before the fixture is returned to its initial position. If desired, the fixture can be designed to vibrate during movement. Also if desired, the epoxy bead can initially be placed in a trough designed to decrease surface-area exposure to the air. Alternatively, the fixture can be kept stationary while the blade is moved.
摘要:
A transducer backing material includes a sticky epoxy resin containing tungsten particles and silver particles. A method of applying a backing material to a transducer includes pouring a mixture of epoxy resin, tungsten particles, and silver particles into a mold containing a layer of piezoelectric material, degassing the mixture, and curing the mixture at a pressure of approximately one atmosphere until the mixture dries.
摘要:
A catheter assembly includes an elongate catheter body having a proximal end and a distal end with a drive cable disposed therein, the drive cable having a proximal end and a distal end, and rotatable relative to the catheter body. A first electro-magnetic element is disposed proximate the distal end of the catheter, and a second electro-magnetic element disposed proximate the distal end of the drive cable and in electrical communication with an operative element mounted at the end of the drive cable, the first and second electro-magnetic elements forming an inductive coupler. The catheter assembly can include various other distal operative elements, which are in communication with corresponding proximal operative elements via transmission lines embedded within the wall of the catheter body.
摘要:
An ultrasound catheter wherein a rotatable transducer couples to the input of a preamplifier. Protection circuits at the input and output of the preamplifier protect the preamplifier from the transducer excitation signal. The preamplifier couples to the distal end of a transmission line. In an alternate embodiment, at least one switch responds to the presence of the transducer excitation signal by coupling the transducer excitation signal to the rotatable transducer and protecting the preamplifier from the transducer excitation signal. The at least one switch responds to the absence of the transducer excitation signal by coupling a received signal produced by the rotatable transducer to the input of the preamplifier. The at least one switch further responds to the absence of the transducer excitation signal by coupling the output of the preamplifier to the distal end of the transmission line.
摘要:
An ultrasonic transducer includes a transducer element having a backing element bonded thereto. The thickness of the backing element is selected to be less than or equal to half the length of an ultrasonic pulse, expressed in wavelengths of the center frequency of the pulse, so that the first reflection from the back side of the backing element is received by the transducer element before the primary pulse rings down. A method for mounting the transducer that reduces the formation of air bubbles includes the steps of forming a peaked mound and continually lowering the transducer to flatten the mound against the underside of the transducer.
摘要:
Systems and methods stimulate circulatory activity in a targeted body region of an individual by applying ultrasound energy. Before, during or after the application of ultrasound energy, the systems and methods administer an agent to individual that results, e.g., in an angiogenic effect, or in a reduction of blood perfusion, or a chemotherapy effect. The application of ultrasound energy selectively increases blood perfusion or uptake of the agent in the targeted body region.