Acoustic imaging and doppler catheters and guidewires

Claim 2

A medical device for making Doppler measurements and imaging within a body fluid conduit using a single transducer, comprising: an elongated device body defining a device axis and constructed for positioning a distal end of said device body near a region of interest in said body fluid conduit, and, disposed within said device body, a transducer constructed to emit a beam of ultrasonic energy having a single frequency, and an ultrasonic beam-directing assembly constructed to direct a first portion of said ultrasonic energy from a single transducer in a direction for imaging within said body fluid conduit and to direct a second portion of said ultrasonic energy in a different direction for making Doppler measurements within said body fluid conduit.

Claim 3

The device of claim 1 wherein said portion of said ultrasonic energy is directed in a direction generally transverse to said device axis for imaging within said body fluid conduit and said other portion of said ultrasonic energy is directed in a direction generally along said device axis for making Doppler measurements within said body fluid conduit.

Claim 4

The device of claim 1 wherein said ultrasonic beam-directing assembly includes an ultrasonic beam splitter to spatially separate ultrasonic energy from said transducer into one portion for providing an image of a wall of a body lumen and another portion for making Doppler measurements of the flow of fluid in said body conduit.

Claim 5

The device of claim 3, further comprising means for varying the transmissivity and reflectivity of said beam-directing assembly by varying the acoustic impedance of said ultrasonic beam splitter.

Claim 6

The device of claim 4, further comprising means for varying the impedance of said ultrasonic beam splitter by flowing fluids of varying impedance behind said ultrasonic beam splitter.

Claim 7

The device of claim 4 wherein said beam splitter is a partially sonolucent beam directing material spaced from said transducer in the path of said ultrasonic energy, and wherein the thickness of said partially sonolucent beam-directing material is pre-selected to obtain a desired impedance of said ultrasonic beam splitter.

Claim 8

The device of claim 1 wherein said other portion of ultrasonic energy for making Doppler measurements is directed at an exit angle of 15° or less with respect to the device axis.

Claim 9

The device of claim 1 wherein the distal end of said device body is open.

Claim 10

The device of claim 1 wherein the distal end of said device body is closed and comprises sonolucent material.

Claim 11

The device of claim 1 further comprising an analysis circuit that includes a timing circuit and a switch such that the ultrasonic imaging signal from said portion of ultrasonic energy for imaging can be differentiated from the ultrasonic Doppler signal from said other portion of ultrasonic energy for making Doppler measurements by time delay between said signals, and said ultrasonic imaging signal and said Doppler signal can be separately analyzed by imaging and Doppler electronics.

Claim 12

The device of claim 1 wherein said transducer is mounted on a hinge constructed to permit said transducer to rotate between at least two angles.

Claim 13

The device of claim 1 wherein at least two facets are mounted on said transducer constructed to permit said transducer to emit ultrasonic energy in two spatially separate directions simultaneously.

Claim 14

A medical device for making Doppler measurements and imaging within a body fluid conduit using a single transducer, comprising: an elongated device body defining a device axis and constructed for positioning a distal end of said device body near a region of interest in said body, an ultrasonic beam directing assembly constructed to direct a portion of ultrasonic energy from a single transducer in a direction for imaging within said body fluid conduit and to direct another portion of said ultrasonic energy in a different direction for making Doppler measurements within said body fluid conduit, said ultrasonic beam-directing assembly comprising an ultrasonic beam splitter to spatially separate ultrasonic energy from said transducer into one portion for providing an image of a wall of a body fluid conduit and another portion for making Doppler measurements of the flow of fluid in said body conduit, wherein said beam splitter is a partially sonolucent polymeric material spaced from said transducer in the path of said ultrasonic energy.

Claim 15

A medical device for making Doppler measurements and imaging within a body fluid conduit using a single transducer, comprising: an elongated device body defining a device axis and constructed for positioning a distal end of said device body near a region of interest in said body, an ultrasonic beam directing assembly constructed to direct a portion of ultrasonic energy from a single transducer in a direction for imaging within said body fluid conduit and to direct another portion of said ultrasonic energy in a different direction for making Doppler measurements within said body fluid conduit, said ultrasonic beam-directing assembly comprising an ultrasonic beam splitter to spatially separate ultrasonic energy from said transducer into one portion for providing an image of a wall of a body fluid conduit and another portion for making Doppler measurements of the flow of fluid in said body conduit, wherein said beam splitter is a partially sonolucent polymeric material spaced from said transducer in the path of said ultrasonic energy.

Claim 16

The device of claim 13 wherein said partially sonolucent polymeric material is located transversely with respect to said device axis.

Claim 17

The device of claim 13 wherein said partially sonolucent polymeric material forms at least a portion of the wall of said device body.

Claim 18

The device of claim 15 wherein the wall of said device body is shaped to efficiently direct said portion of energy for making Doppler measurements generally along the axis of said device body.

Claim 19

The device of claim 16 wherein said device body has a flared distal end.

Claim 20

A medical device for making Doppler measurements and imaging within a body fluid conduit using a single transducer, comprising: an elongated device body defining a device axis and constructed for positioning a distal end of said device body near a region of interest in said body fluid conduit, and, disposed within said device body, an ultrasonic beam-directing assembly constructed to direct a portion of ultrasonic energy from a single transducer in a direction for imaging within said body fluid conduit and to direct another portion of said ultrasonic energy in a different direction for making Doppler measurements within said body fluid conduit, wherein said beam-directing assembly, is an acoustically reflective ring disposed within said device body, a portion of said device body being formed from a sonolucent material.

Claim 21

A medical device for making Doppler measurements and imaging within a body fluid conduit using a single transducer, comprising: an elongated device body defining a device axis and constructed for positioning a distal end of said device body near a region of interest in said body fluid conduit, and, disposed within said device body, an ultrasonic beam-directing assembly constructed to direct a portion of ultrasonic energy from a single transducer in a direction for imaging within said body fluid conduit and to direct another portion of said ultrasonic energy in a different direction for making Doppler measurements within said body fluid conduit, wherein said beam-directing assembly, is an acoustically reflective ring disposed within said device body, a portion of said device body being formed from a sonolucent material.

Claim 24

A method as in claim 19, wherein the ultrasonic beam-directing assembly is an ultrasonic beam splitter which spatially separates said ultrasonic signal from said transducer into said first portion for providing an image of a wall of said body fluid conduit and said second portion for making Doppler measurements of the flow of fluid in said body fluid conduit.