Artifact reduction for volume acquisition

Abstract

Motion artifacts are reduced for three- or four-dimensional imaging with a mechanically rocked array by determining a position of a scan within a volume as a function of velocity. A represented position within a volume of a mechanically rocked scan is determined. Differences in velocity associated with different scan plane positions are used to alter or adjust a scan position. For example, the start position for a transmit operation or the spatial location represented by previously acquired data is altered as a function of a corresponding velocity in the mechanical movement of the array. Variation in velocity results in different relative scan positions or adjustments within the volume. The velocity variation is determined in an open loop, such as from previously measured or expected velocity of the array, or from feedback from actual measured position and associated velocity of the array.

1 . A method for determining a position of a mechanically rocked scan within a volume, the method comprising: 
 (a) determining first and second velocity parameters of a mechanically rocked array at first and second different positions, respectively, the velocity parameter being different at each of the first and second positions; and    (b) setting first and second scan positions as a function of the first and second velocity parameters, respectively;    wherein (b) comprises setting a spatial relationship of previously acquired data as a function of the first and second velocities.    
   
   
       2 . A system for determining a position of a mechanically rocked scan within a volume, the system comprising: 
 a mechanically rocked array; and    a beamformer operable to set first and second scan positions as a function of first and second different velocity parameters, respectively, of the mechanically rocked array.    
   
   
       3 . The system of  claim 2  further comprising: 
 an encoder connected with the array;    wherein the beamformer is operable to determine an array velocity parameter in response to inputs from the encoder.    
   
   
       4 . The system of  claim 2  wherein the beamformer is operable to set a transmit position of a start of a planar scan as a function of the first velocity parameter.  
   
   
       5 . A method for determining a position of a mechanically rocked scan within a volume, the method comprising: 
 (a) determining first and second velocity parameters of a mechanically rocked array at first and second different positions, respectively, the velocity parameter being different at each of the first and second positions; and    (b) electronically setting frame trigger positions as a function of the first and second velocity parameters, respectively.