Experimental Cross-Talk Reduction for 3D Multi Line Transmission

The necessity of frame rate enhancement is particularly important in 3D echocardiography since full-volume acquisitions at a quality comparable to 2D imaging require increasing the number of transmissions. Despite the potential of Multi Line Transmission (MLT) in providing high frame rates while preserving the image quality, this method has a non-negligible limitation: the presence of cross-talks artefacts. The objective of this study was to investigate experimentally if cross-talk reduction can be achieved by replacing the typical alignment of the transmissions parallel to the element lines or columns by an alignment along the transverse diagonal of the transducer. The results showed that the diagonal transmission provides a better axial resolution than the linear one. Additionally, as the principal cause of cross-talk artefacts is the interference between the main lobe and the side lobes of parallel transmissions, we measured the values of these lobes in the two cases. The main lobe was up to 5% higher than the side lobe for the linear transmission and up to 25 % higher for the diagonal one. However, the cross talk reduction was achieved with the cost of Contrast to Noise Ratio (CNR), which was three times lower for the diagonal transmission compared to the linear one.