Abstract: An ultrasound catheter is disclosed 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.

Abstract: 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.

Abstract: 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.

Abstract: Systems and methods for exchanging ultrasound and X-ray video signals are disclosed. The system may select an analog X-ray input signal from, for example, either a fluoroscopic or roadmap video signal according to user input. The analog X-ray input signal is digitized and converted using the appropriate video conversion factors to a standard high-resolution format suitable for display on, for example, an intravascular ultrasound monitor. The digitized X-ray signal is electrically isolated from the graphics cards operating the intravascular ultrasound display. The system also digitizes high-resolution ultrasound video and converts it to a format suitable for display on a hospital X-ray monitor. The converted and digitized ultrasound video is electrically isolated from the hospital X-ray monitors.

Abstract: The present invention provides for catheter systems and methods of their use. In one embodiment, the invention provides a catheter comprising a catheter body having a proximal end, a distal end and a working lumen. A drive cable is disposed within the lumen and at least one transducer is attached to the cable near the distal end. A rotary transformer is included, comprising a transformer stator which is spaced apart from a transformer rotor. The rotor is operably attached to the cable to rotate therewith. The rotor is electrically coupled to the transducer and is magnetically coupled to the stator to allow a signal to be transmitted from the transducer to the stator during rotation of the cable.

Abstract: An ultrasound imaging system with a slewing bandpass filter is disclosed for selective passage of time varying acoustic signals. The acoustic signals represent artifacts of reflection of tissue and fluid. The bandpass filter includes two mixers and two fixed bandpass filters. The signal sources each provide a reference signal for two local oscillators. The first mixer mixes the input and first reference signals to a desired first frequency range. The first fixed bandpass filter has a top passband frequency above the first frequency range and provides a first filtered output signal. The second mixer mixes the first filtered signal and the second reference signal to a desired second frequency range. The second fixed bandpass filter has a center frequency and bandwidth not overlapping with the first bandpass filter.