Effect of Imaging Parameters on the Visualization of Lung Ultrasound B-line Artifacts

Lung ultrasound (LUS) is mainly based on the qualitative evaluation of the vertical artifacts called B-lines. To quantitatively evaluate the state of the lung, the B-lines' genesis need to be studied. An ambiguity on the formation of B-lines leads to the formulation of two main hypotheses. While the first associates the B-lines' visualization only with the emitted beam's dimension, the second links their visualization to specific resonance phenomena. This paper aims at verifying these hypotheses by studying the frequency characterization of B-lines detected in dedicated lung-phantoms. Raw radio frequency (RF) data was acquired by means of a multifrequency approach. We exploited the total intensity parameter to measure the B-lines' strength as a function of frequency, focal point and transmitting aperture. According to the results, the frequency is the main parameter that influences the appearance of B-lines.