Initial results from a forward-viewing ring-annular ultrasound array for intravascular imaging

In this paper, we present some initial results from our proposed forward viewing ring-annular array for intravascular ultrasound imaging. We have investigated array design and image synthesis allowing simultaneous sideward imaging at 20 MHz and forward imaging at 10 MHz from the same array. This design is appropriate for over-the-wire delivery but limits the forward-looking aperture to a ring-annular array. In particular, a 1200 /spl mu/m diameter ring-annular array with 64 elements has been constructed. The measured forward- viewing radiation pattern of an individual element indicates an acceptance angle range of over 90/spl deg/. Currently, there are significant sensitivity and center frequency variations among the elements. Nevertheless, images of point targets are obtained as a proof-of-concept. Future improvements of the array will be discussed.

[1]  H H Quick,et al.  Vascular stents as RF antennas for intravascular MR guidance and imaging , 1999, Magnetic resonance in medicine.

[2]  Ogan Ocali,et al.  Intravascular magnetic resonance imaging using a loopless catheter antenna , 1997, Magnetic resonance in medicine.

[3]  K. Metzger,et al.  Coded EXcitation with spectrum inversion (CEXSI) for ultrasound array imaging , 2003, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[4]  Michael J. Vonesh,et al.  Arterial Imaging With a New Forward‐Viewing Intravascular Ultrasound Catheter, II: Three‐Dimensional Reconstruction and Display of Data , 1994, Circulation.

[5]  D.N. Stephens,et al.  Optimizing the beam pattern of a forward-viewing ring-annular ultrasound array for intravascular imaging , 2002, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[6]  Stephen J. Norton.  Annular array imaging with full‐aperture resolution , 1992 .

[7]  G.R. Lockwood,et al.  Broad-bandwidth radiation patterns of sparse two-dimensional vernier arrays , 1997, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[8]  Michael J. Vonesh,et al.  Arterial Imaging With a New Forward‐Viewing Intravascular Ultrasound Catheter, I: Initial Studies , 1994, Circulation.

[9]  Yao Wang,et al.  A forward-viewing ring-annular array for intravascular ultrasound imaging , 2001, 2001 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.01CH37263).

[10]  M. O'Donnell,et al.  Modified Weighting Method for Forward-Looking Ring-Annular Arrays , 2001, Ultrasonic imaging.

[11]  W N McDicken,et al.  Three-dimensional forward-viewing intravascular ultrasound imaging of human arteries in vitro. , 2001, Ultrasound in medicine & biology.

[12]  R. T. Hoctor,et al.  The unifying role of the coarray in aperture synthesis for coherent and incoherent imaging , 1990, Proc. IEEE.

[13]  Compounding for a Forward-Viewing Ring-Annular Ultrasound Array System , 2001, Ultrasonic imaging.

[14]  G.R. Lockwood,et al.  Real-time 3-D ultrasound imaging using sparse synthetic aperture beamforming , 1998, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[15]  B S Hu,et al.  A forward-viewing intravascular ultrasound catheter suitable for intracoronary use. , 1997, Biomedical instrumentation & technology.

[16]  M. O'Donnell,et al.  Synthetic phased arrays for intraluminal imaging of coronary arteries , 1997, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.