An ultrasound imaging system for shear wave imaging comprising: an ultrasound transducer configured to acquire echoes responsive to ultrasound pulses transmitted toward a bounded target tissue, wherein the bounded target tissue comprises thin tissue of finite size; a beamformer (221, 222) configured to: transmit, from the ultrasound transducer, tracking pulses in response to a push pulse, wherein the push pulse generates shear waves in the bounded target tissue and the tracking pulses are spatially planned to intersect the shear waves at one or more locales; and receive, from the ultrasound transducer, echo signals where the tracking pulses intersected the shear waves; and a processor in communication with the beamformer (221, 222) and configured to: store tracking echo data generated from the received echo signals; apply a directional filter to the tracking echo data to generate directionally filtered shear wave data based on a dimension of the bounded target tissue and an angular orientation (alpha) of the bounded target tissue relative to the ultrasound transducer so as to remove unwanted noise generated by shear waves reverberating off bounded target tissue boundaries and interfaces between the bounded target tissue and surrounding tissues or substances; estimate velocities of the shear waves along the bounded target tissue at different shear wave frequencies based on the filtered shear wave data and angular orientation (alpha) of the bounded target tissue relative to the ultrasound transducer; and determine a stiffness value of the bounded target tissue using the estimated velocities and at least one dimensional parameter of the tissue. an ultrasound transducer configured to acquire echoes responsive to ultrasound pulses transmitted toward a bounded target tissue, wherein the bounded target tissue comprises thin tissue of finite size; a beamformer (221, 222) configured to: transmit, from the ultrasound transducer, tracking pulses in response to a push pulse, wherein the push pulse generates shear waves in the bounded target tissue and the tracking pulses are spatially planned to intersect the shear waves at one or more locales; and receive, from the ultrasound transducer, echo signals where the tracking pulses intersected the shear waves; and transmit, from the ultrasound transducer, tracking pulses in response to a push pulse, wherein the push pulse generates shear waves in the bounded target tissue and the tracking pulses are spatially planned to intersect the shear waves at one or more locales; and receive, from the ultrasound transducer, echo signals where the tracking pulses intersected the shear waves; and a processor in communication with the beamformer (221, 222) and configured to: store tracking echo data generated from the received echo signals; apply a directional filter to the tracking echo data to generate directionally filtered shear wave data based on a dimension of the bounded target tissue and an angular orientation (alpha) of the bounded target tissue relative to the ultrasound transducer so as to remove unwanted noise generated by shear waves reverberating off bounded target tissue boundaries and interfaces between the bounded target tissue and surrounding tissues or substances; estimate velocities of the shear waves along the bounded target tissue at different shear wave frequencies based on the filtered shear wave data and angular orientation (alpha) of the bounded target tissue relative to the ultrasound transducer; and determine a stiffness value of the bounded target tissue using the estimated velocities and at least one dimensional parameter of the tissue. store tracking echo data generated from the received echo signals; apply a directional filter to the tracking echo data to generate directionally filtered shear wave data based on a dimension of the bounded target tissue and an angular orientation (alpha) of the bounded target tissue relative to the ultrasound transducer so as to remove unwanted noise generated by shear waves reverberating off bounded target tissue boundaries and interfaces between the bounded target tissue and surrounding tissues or substances; estimate velocities of the shear waves along the bounded target tissue at different shear wave frequencies based on the filtered shear wave data and angular orientation (alpha) of the bounded target tissue relative to the ultrasound transducer; and determine a stiffness value of the bounded target tissue using the estimated velocities and at least one dimensional parameter of the tissue.