Abstract: An apparatus and method for operating a catheter guiding assembly, with one lumen providing access for an ultrasound imaging catheter and a second lumen providing a working port for a tool. Optionally, the ultrasound imaging catheter in the catheter guiding assembly is exposed to blood, and the ultrasound imaging catheter port has a gasket. Alternatively, the catheter guiding assembly is sealed to prevent blood contact by the ultrasound imaging catheter, and the ultrasound imaging catheter may be re-used several times. In either case, the working tool is in the field of view of the ultrasound imaging catheter and normally exposed to blood. Because the working tool is exposed to blood, the working port has a gasket to keep blood from leaking out. Optionally, the working port is used for fluid delivery for injecting contrast agent, chemicals or drugs, which can be activated by sonification from the ultrasound imaging catheter.

Abstract: An ultrasonic transducer assembly includes a conduit that defines a lumen, and the lumen carries a flexible circuit. The flexible circuit can take several forms. In one form the circuit is folded at first and second fold lines, and at least one of the folds is oriented obliquely to the longitudinal axis of conduit. In another form the flexible circuit includes an end portion that defines a plurality of substantially parallel grooves, each groove aligned with and exposing a respective one of the conductors of the circuit. Additional conductors are positioned in respective ones of the grooves and are electrically connected with the respective conductors of the flexible circuit.