Intravascular Ultrasonic Catheter Arrangements

Abstract

Devices, systems, and methods for intravascular ultrasonic imaging are provided. In one embodiment, an apparatus for intravascular ultrasonic imaging is provided. The apparatus includes a flexible elongate member sized for insertion within a vasculature; an ultrasonic transducer array, mounted proximate a distal end of the flexible elongate member, wherein transducer elements of the ultrasonic transducer array comprise a non-polymeric electrostrictive material; and a high permittivity ceramic member that signally couples a common radiofrequency signal source to all elements of the transducer array simultaneously such that the common radiofrequency signal is provided through the ceramic member to all the transducer elements of the ultrasonic transducer array and a bias field is selectively transmitted to one or more of the transducer elements such that only transducer elements having the bias field applied to them will transform the common radiofrequency signal into an ultrasonic signal.

1 - 18 . (canceled) 
     
     
         19 . An apparatus for intravascular ultrasonic imaging, the apparatus comprising:
 a flexible elongate member sized for insertion within a vasculature;   an ultrasonic transducer array, mounted proximate a distal end of the flexible elongate member, wherein transducer elements of the ultrasonic transducer array comprise a non-polymeric electrostrictive material; and   a high permitivity ceramic member that signally couples a common radiofrequency signal source to all elements of the transducer array simultaneously such that the common radiofrequency signal is provided through the ceramic member to all the transducer elements of the ultrasonic transducer array and a bias field is selectively transmitted to one or more of the transducer elements such that only transducer elements having the bias field applied to them will transform the common radiofrequency signal into an ultrasonic signal.   
     
     
         20 . The apparatus of  claim 19 , wherein the electrostrictive material is a relaxor ferroelectric material. 
     
     
         21 . The apparatus of  claim 20 , wherein the electrostrictive material comprises lead magnesium niobate. 
     
     
         22 . The apparatus of  claim 19 , further comprising a multiplexer arrangement through which the bias field is selectively applied to one or more of the transducer elements and through which echo signals received by the transducer array are passed to the proximal end of the flexible elongate member. 
     
     
         23 . The apparatus of  claim 22 , wherein the multiplexer arrangement comprises a plurality of integrated circuits. 
     
     
         24 . The apparatus as claimed in  claim 23 , wherein the transducer array is arranged in a substantially cylindrical configuration. 
     
     
         25 . The apparatus of  claim 23 , wherein adjacent integrated circuits are spaced from one another by a slot. 
     
     
         26 . The apparatus of  claim 23 , wherein the integrated circuits are flip-chip bonded to an electrical circuit. 
     
     
         27 . The apparatus of  claim 26 , wherein the electrical circuit comprises a printed circuit. 
     
     
         28 . The apparatus of  claim 19 , wherein the transducer array comprises:
 a substrate;   electrically conductive tracks on the substrate; and   a set of individual transducer array elements created by forming slots in a piezoelectric block.   
     
     
         29 . The apparatus of  claim 28 , further comprising at least one multiplexer circuit coupled to the electrically conductive tracks. 
     
     
         30 . The apparatus of  claim 28 , further comprising slot bottoms formed in the substrate adjacent the electrically conductive tracks. 
     
     
         31 . The apparatus of  claim 30 , wherein the slot bottoms are formed with a laser. 
     
     
         32 . The apparatus of  claim 19 , wherein the flexible elongate member is a catheter. 
     
     
         33 . The apparatus of  claim 19 , wherein the high permitivity ceramic member capacitatively couples the common radiofrequency signal source to signal lines that selectively carry a DC bias voltage signal to individual ones of the elements of the transducer array. 
     
     
         34 . The apparatus of  claim 33 , wherein a multiplexer selectively provides the DC bias voltage signal to individual ones of the transducer elements of the transducer array. 
     
     
         35 . The apparatus of  claim 33 , wherein the electrostrictive material of the transducer elements comprises ferroelectric relaxor material. 
     
     
         36 . The apparatus of  claim 33 , wherein the electrostrictive material of the transducer elements comprises lead magnesium niobate. 
     
     
         37 . An apparatus for intravascular ultrasonic imaging, the apparatus comprising:
 a flexible elongate member sized for insertion within a vasculature;   an ultrasonic transducer array mounted proximate a distal end of the flexible elongate member, the array comprising a plurality of ultrasonic transducer elements, each comprising a non-polymeric electrostrictive material;   a multiplexer configured to selectively transmit a DC bias voltage to the plurality of ultrasonic transducer elements; and   a common high permitivity ceramic member configured to simultaneously electrically couple all the transducer elements to each other and to a common radiofrequency signal source;   wherein the common radiofrequency signal is provided through the ceramic member to all of the transducer elements of the ultrasonic transducer array and the DC bias voltage is selectively transmitted to one or more of the transducer elements such that only transducer elements having the DC bias voltage applied to them will transform the common radiofrequency signal into an ultrasonic signal.