By Melissa Yin, Applications Specialist and Dr. Sarah Burris, Scientific Liaison.
Recently, we have seen an increased demand for ultrasound imaging in hospitals as the global medical community treats increasing numbers of COVID-19 patients. Although not traditionally considered as a common application, ultrasound imaging has proven itself as a useful tool for the diagnosis and monitoring of acute respiratory failure and its causes. Lung ultrasound (LUS) imaging rivals CT as a fast and accurate bedside tool and has gained popularity in its use in the ICU and emergency departments to provide a radiation-free diagnosis of many pleural and lung pathologies. Below, we share some key findings from several publications that use ultrasound imaging systems from the FUJIFILM VisualSonics product portfolio to diagnose and monitor lung pathologies in pre-clinical rodent models.
“From bedside to bench: lung ultrasound for the assessment of pulmonary edema in animal models”
The increased use of LUS in clinical settings has also incited interests in its use in preclinical research. As small animals models mimicking lung congestion and pulmonary edema formation are being developed, LUS offers the potential for researchers to conduct studies non-invasively and longitudinally. In this recent publication by Grune et al, the authors review the current use of LUS in the clinical setting, and the translation of established techniques to preclinical research. They conclude that LUS imaging is a cost-effective method to assess pulmonary edema in small animal models. In addition, this method may help to reduce the number of experimental animals due to the possibility of serial evaluations in the same animal as compared with traditional end-point experiments.
“Lung ultrasound is a reliable method for evaluating extravascular lung water volume in rodents”
Although the use of LUS in preclinical research is still in its initial phase, Ma et al, published the first ultrasonic evaluation of extravascular lung water (EVLW) in rats using a model of acute lung injury. Using a modified 28-rib space technique adapted from clinical protocols, the authors compared this method to traditional post-mortem gravimetric analysis and showed strong correlations. Repeatability studies of the LUS technique also showed good intra-observer and inter-observer reproducibility.
“Lung ultrasound as a translational approach for non-invasive assessment of heart failure with reduced or preserved ejection fraction in mice”
The use of LUS has also been shown to be a valuable tool for the diagnosis of heart failure (HF) in preclinical models, where cardiac dysfunctions are not present when evaluated by traditional echo techniques. This was published in a study by Villalba-Orero et al, showing that the combination of LUS with echocardiography can provide diagnosis of HF with preserved or reduced ejection fractions in mice.
References:
From bedside to bench: lung ultrasound for the assessment of pulmonary edema in animal models. Grune et al. Cell and Tissue Research (2020) https://doi.org/10.1007/s00441-020-03172-2
Lung ultrasound is a reliable method for evaluating extravascular lung water volume in rodents. Ma et al. BMC Anesthesiology (2015) 15:162 DOI 10.1186/s12871-015-0146-1.
Lung ultrasound as a translational approach for non-invasive assessment of heart failure with reduced or preserved ejection fraction in mice. Villalba-Orero et al. Cardiovasc Res. 2017 Aug 1;113(10):1113-1123. doi: 10.1093/cvr/cvx090.