Figure 5.

The influence of ultrasound transducers and transducer frequency on BLA visualization was examined in a patient with mixed lung fibrosis and edema and focal pleural irregularities. The examinations were performed using Acuson Sequoia with different multifrequency transducers, 3V2c-S (cardiac), 4C1-S (curved array abdominal), 8L5 (linear), 15L8w-S (linear). The images demonstrate that the focal pleural irregularity was only detected using the high frequency probes, which might influence the imaging characteristics and accompanying signs in BLA patterns. The sequence demonstrates that not all transducers show the same findings. Influencing factors were the transducer itself, frequency used, harmonic imaging (HI), depth penetration, focus zone. The 3V2c-S (2 MHz) (A) and 4C1-S (4 MHz) (B) transducers showed multiple BLA indicating both fibrosis and edema. The amount of BLA and the surrounding artefacts were different. Multiple BLA were detected using 8.0 MHz with harmonic imaging (C) and less without harmonic (D). The “sound of lung water” (pulmonary edema) is best shown by 8L5 using 5.0 MHz (E). The 15L8w-S transducer revealed multiple BLA with 10.0 MHz (F). BLA, B-line artifact.