Clutter suppression for synthetic aperture ultrasound

Abstract

Solid-state ultrasound imaging devices, systems, and methods are provided. Some embodiments of the present disclosure are particularly directed to identifying and removing artifacts in ultrasound data due to side lobes, grating lobes, and/or other effect. In some embodiments, an ultrasound processing system includes an interface operable to receive A-line signal data and a focusing engine operable to perform a focusing process on the received A-line signal data to produce focused A-line signal data. The ultrasound processing system also includes a coherency unit operable to determine a measurement of coherency of the received A-line signal data. The ultrasound processing system further includes an adjustment unit operable to determine an adjustment to the focused A-line signal data based on the measurement of coherency, and a compensation unit operable to apply the adjustment to the focused A-line signal data.

What is claimed is: 
     
         1 . An ultrasound imaging system comprising:
 electronic circuitry in communication with an intravascular ultrasound (IVUS) imaging device configured to be positioned within a vessel of a patient, the electronic circuitry configured to:
 receive unfocused A-line signal data obtained by the IVUS imaging device; 
 perform a focusing process on the unfocused A-line signal data to produce focused A-line signal data; 
 determine a measurement of phase coherency of the unfocused A-line signal data; 
 determine an adjustment to the focused A-line signal data based on a comparison of the measurement of phase coherency to a phase coherence threshold; and 
 apply the adjustment to the focused A-line signal data. 
   
     
     
         2 . The ultrasound imaging system of  claim 1 , wherein the measurement of phase coherency is an indication of artifacts within the unfocused A-line signal data, and wherein the adjustment is determined to suppress the artifacts. 
     
     
         3 . The ultrasound imaging system of  claim 1 , wherein the measurement of phase coherency is based on at least one of: a sign or a phase angle of the unfocused A-line signal data. 
     
     
         4 . The ultrasound imaging system of  claim 1 , wherein the measurement of phase coherency is based on a sign of the unfocused A-line signal data, and wherein the sign represents at least one of a voltage polarity or a variance from a reference voltage. 
     
     
         5 . The ultrasound imaging system of  claim 1 , wherein the electronic circuitry is further configured to:
 assign a sign value to the unfocused A-line signal data based on a sign of the unfocused A-line signal data;   add the sign value to a sign value total for a set of A-lines of an aperture corresponding to the focused A-line signal data; and   determine the measurement of phase coherency based on the sign value total.   
     
     
         6 . The ultrasound imaging system of  claim 5 , wherein the electronic circuitry is further configured to normalize the sign value total based on a count of A-lines in the aperture, and wherein the measurement of phase coherency is further based on the normalized sign value total. 
     
     
         7 . The ultrasound imaging system of  claim 1 , wherein the electronic circuitry is further configured to:
 determine a phase angle of the unfocused A-line signal data after a time-of-flight adjustment;   determine, based on the phase angle, a normalized phase angle for a set of A-lines of an aperture corresponding to the focused A-line signal data; and   determine the measurement of phase coherency based on the normalized phase angle.   
     
     
         8 . The ultrasound imaging system of  claim 7 , wherein the electronic circuitry is configured to convert the A-line signal data into a baseband representation. 
     
     
         9 . The ultrasound imaging system of  claim 1 , wherein the adjustment is applied based on the measurement of phase coherency exceeding the phase coherence threshold. 
     
     
         10 . The ultrasound imaging system of  claim 1 , wherein the adjustment is a coherency-based adjustment, and wherein the electronic circuitry is further configured to:
 determine a magnitude of the focused A-line signal data;   determine an intensity-based adjustment to the focused A-line signal data based on the magnitude of the focused A-line signal data; and   apply the intensity-based adjustment to the focused A-line signal data.   
     
     
         11 . The ultrasound imaging system of  claim 10 , wherein the intensity-based adjustment is directly proportional to the magnitude of the focused A-line signal data. 
     
     
         12 . The ultrasound imaging system of  claim 1 , further comprising the IVUS imaging device. 
     
     
         13 . The ultrasound imaging system of  claim 1 , wherein the phase coherence threshold is associated with at least one of a range or a beam angle of the focused A-line signal data.