A method of forming an ultrasound image, using an ultrasound imaging system, the method comprising: transmitting an unfocused first circular wave front ultrasound signal into a region of interest from a first transmit aperture (n, j, k) and receiving echoes of the first circular wave front ultrasound signal at a first receive aperture (13, 15) to form a first image layer; transmitting an unfocused second circular wave front ultrasound signal into a region of interest from a second transmit aperture (n, j, k) and receiving echoes of the second circular wave front ultrasound signal at the first receive aperture (13, 15) to form a second image layer; applying a weighting factor to at least one pixel of the first image layer to obtain a modified first image layer, wherein applying the weighting factor decreases the contribution to the first image layer made by pixels that are identified as likely to contain more than a threshold level of noise; and combining the modified first image layer with the second image layer to form a combined image; wherein, prior to applying the weighting factor, a value of the weighting factor is determined by evaluating a quality of a point-spread-function of the first transmit aperture (n, j, k) and the first receive aperture (13, 15), determining that a pixel image obtained using the first transmit aperture and the first receive aperture will improve image quality, and assigning a non-zero positive value to the weighting factor; or wherein, prior to applying the weighting factor, a value of the weighting factor is determined by evaluating a quality of a point-spread-function of the first transmit aperture (n, j, k) and the first receive aperture (13, 15), determining that a pixel image obtained using the first transmit aperture and the first receive aperture will degrade image quality, and assigning a value of zero to the weighting factor. transmitting an unfocused first circular wave front ultrasound signal into a region of interest from a first transmit aperture (n, j, k) and receiving echoes of the first circular wave front ultrasound signal at a first receive aperture (13, 15) to form a first image layer; transmitting an unfocused second circular wave front ultrasound signal into a region of interest from a second transmit aperture (n, j, k) and receiving echoes of the second circular wave front ultrasound signal at the first receive aperture (13, 15) to form a second image layer; applying a weighting factor to at least one pixel of the first image layer to obtain a modified first image layer, wherein applying the weighting factor decreases the contribution to the first image layer made by pixels that are identified as likely to contain more than a threshold level of noise; and combining the modified first image layer with the second image layer to form a combined image; wherein, prior to applying the weighting factor, a value of the weighting factor is determined by evaluating a quality of a point-spread-function of the first transmit aperture (n, j, k) and the first receive aperture (13, 15), determining that a pixel image obtained using the first transmit aperture and the first receive aperture will improve image quality, and assigning a non-zero positive value to the weighting factor; or wherein, prior to applying the weighting factor, a value of the weighting factor is determined by evaluating a quality of a point-spread-function of the first transmit aperture (n, j, k) and the first receive aperture (13, 15), determining that a pixel image obtained using the first transmit aperture and the first receive aperture will degrade image quality, and assigning a value of zero to the weighting factor.