Patent ID: 8273026
Filing Date: 2012-09-25
Classification: A61B,G01S

Abstract:
1. An ultrasonic imaging method comprising the steps of: providing a linear ultrasound probe comprising a plurality of transducers which are placed side by side along a line forming a linear array; providing a B-mode imaging scanning unit to which said transducers are connected and which alternatively generates electric driving signals for each of said transducers of said probe for exciting said transducers to emit ultrasound transmission signals and to receive electric signals generated by each of said transducers due to the excitation of said transducers by ultrasound reflection signals reflected from a target body against which said ultrasound transmission signals have been emitted; defining a starting orientation of the direction of propagation of said ultrasound transmission signals and of said ultrasound reflection signals along which a first scanning step is carried out; carrying out said first scanning step by emitting said ultrasound transmission signals and receiving said ultrasound reflection signals along the said starting orientation of said direction of propagation; oscillating said probe in a direction transversal to the longitudinal extension of said linear array of transducers and around an axis coinciding or parallel to said longitudinal extensions or coinciding or parallel to a central longitudinal axis of said linear array of transducers for modifying the orientation of said direction of propagation of said ultrasound transmission signals and of said ultrasound reflection signals; carrying out additional scanning steps along each new oriented direction of Propagation corresponding to a different oscillation angle of said probe; providing a 3-D scan-converter in which received signals related to said Ultrasound reflection signals are stored; providing B-mode image producing means for generating an image from said received signals related to said ultrasound reflection signals; characterized by the steps of: steering said ultrasound transmission signals so that said linear array of transducers generates a trapezoidal scanning plane diverging in the direction of propagation of said transmission signals; carrying out scanning along a number of adjacent scanning lines which are not parallel but are angularly displaced one from the other and are oriented along different angular directions relative to a common center of angular displacement on which common center fall the prolongations of the scanning line in a backward directions relative to the propagation direction; providing a reflection signal focusing rule which generates a trapezoidal image corresponding to said steered ultrasound signals, wherein said ultrasound transmission signals is obtained by providing transducer driving signals having time delays for driving each of said transducer of said array so that said ultrasound transmission signals are focused on a laterally inclined propagation line deviated outwards from lateral limits of an imaged area defined by the projection of said linear array of transducers in a direction perpendicular to a longitudinal extensions of said linear array; creating at least two different sequences of time delayed excitation pulses of said transducers of said linear array of transducers, each of the said sequences including differently steered ultrasound transmission signal and at least two scanning planes corresponding to different oscillation angles of said probe and having different shapes or dimensions; selecting one of said created sequences of time delayed excitation pulses; and applying said selected sequence of time delayed excitation pulses to said transducers for at least part of said scanning planes having different angular orientations.