European Respiratory Society Statement on Thoracic Ultrasound

Thoracic ultrasound is increasingly considered to be an essential tool for the pulmonologist. It is used in diverse clinical scenarios, including as an adjunct to clinical decision making for diagnosis, a real-time guide to procedures, and a predictor or measurement of treatment response. The aim of this European Respiratory Society task force was to produce a statement on thoracic ultrasound for pulmonologists using thoracic ultrasound within the field of respiratory medicine. The multidisciplinary panel performed a review of the literature, addressing major areas of thoracic ultrasound practice and application. The selected major areas include equipment and technique, assessment of the chest wall, parietal pleura, pleural effusion, pneumothorax, interstitial syndrome, lung consolidation, diaphragm assessment, intervention guidance, training, and the patient perspective. Despite the growing evidence supporting the use of thoracic ultrasound, the published literature still contains a paucity of data in some important fields. Key research questions for each of the major areas were identified, which serve to facilitate future multi-centre collaborations and research to further consolidate an evidence-based use of thoracic ultrasound, for the benefit of the many patients being exposed to clinicians using thoracic ultrasound

Diagnostic Ultrasound Safety Review for Point-of-Care Ultrasound Practitioners

Potential ultrasound exposure safety issues are reviewed, with guidance for prudent use of point‐of‐care ultrasound (POCUS). Safety assurance begins with the training of POCUS practitioners in the generation and interpretation of diagnostically valid and clinically relevant images. Sonographers themselves should minimize patient exposure in accordance with the as‐low‐as‐reasonably‐achievable principle, particularly for the safety of the eye, lung, and fetus. This practice entails the reduction of output indices or the exposure duration, consistent with the acquisition of diagnostically definitive images. Informed adoption of POCUS worldwide promises a reduction of ionizing radiation risks, enhanced cost‐effectiveness, and prompt diagnoses for optimal patient care

Imaging biomarkers in the idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIMs) are a group of acquired muscle diseases with muscle inflammation, weakness, and other extra-muscular manifestations. IIMs can significantly impact the quality of life, and management of IIMs often requires a multi-disciplinary approach. Imaging biomarkers have become an integral part of the management of IIMs. Magnetic resonance imaging (MRI), muscle ultrasound, electrical impedance myography (EIM), and positron emission tomography (PET) are the most widely used imaging technologies in IIMs. They can help make the diagnosis and assess the burden of muscle damage and treatment response. MRI is the most widely used imaging biomarker of IIMs and can assess a large volume of muscle tissue but is limited by availability and cost. Muscle ultrasound and EIM are easy to administer and can even be performed in the clinical setting, but they need further validation. These technologies may complement muscle strength testing and laboratory studies and provide an objective assessment of muscle health in IIMs. Furthermore, this is a rapidly progressing field, and new advances are going to equip care providers with a better objective assessment of IIMS and eventually improve patient management. This review discusses the current state and future direction of imaging biomarkers in IIMs

Caractérisation ultrasonore de l'angiogenèse, de l'élasticité et de la microstructure tumorale sous l'effet de thérapies conventionnelles et innovantes

Tumor development is complex process made possible thanks to the microenvironment surrounding tumor cell. Modifications induced by tumor cells on their environment enable their own development by remodeling tissues sustaining them and by creating a new vascular network (angiogenesis). The use of several antiangiogenic therapies, inhibiting the sprout of a new vascular network, has been authorized in clinic. These therapies induce strong modifications in tumors at the functional level and following tumor size changes are is not sufficient to fully characterize tumor modifications. The main goal of this thesis was to use different ultrasound-based imaging modalities in order to assess their sensitivity to modifications induced in murine tumor model (colorectal and lung carcinomas) during different type of therapy (chemical: cytotoxic, antiangiogenic / physical: cold plasma, sonosensitization). Modifications of the spatial distribution of microvessels and their functionality were characterized using contrast-enhanced ultrasound (CEUS), alteration of tumor microstructure was assessed using spectral analysis of radiofrequency signal, known as quantitative ultrasound (QUS) and finally variations of mechanical properties in tumor tissues were measured in shear wave elastography (SWE). In order to better understand the origin of the modifications observed in vivo, standard parameters such as level of fibrosis and necrosis were characterize ex vivo in tumor tissue using immunochemistry as gold standard.Les modifications induites par les cellules tumorales sur leur environnement ont pour but de permettre leur développement en remodelant le tissu la soutenant et en créant un nouveau réseau vasculaire (angiogenèse). Plusieurs thérapies anti-angiogéniques inhibant le développement du réseau vasculaire tumoral ont obtenu l’autorisation de mise sur le marché et sont actuellement utilisées en clinique. Ces thérapies induisent de fortes modifications fonctionnelles au sein de la tumeur mais le simple suivi de l’évolution du volume tumoral n’est pas suffisant pour rendre compte de ces modifications. L’objectif principal de la thèse a consisté à utiliser différentes modalités d’imagerie ultrasonore afin d’évaluer leur sensibilité aux modifications générées dans des tumeurs murine (carcinome colorectal et pulmonaire) au cours de plusieurs types de thérapie (chimique : cytotoxique, anti-angiogénique / physique : plasma froid, sono-sensibilisation). Les modifications de la distribution spatiale des micro-vaisseaux et leur fonctionnalité ont été caractérisées à l’aide de l’imagerie de contraste ultrasonore (CEUS), l’altération de la microstructure de la tumeur a été évaluée grâce à l’analyse spectrale des signaux radiofréquences, connu comme « quantitative ultrasound » (QUS) et enfin les variations des propriétés mécaniques des tissus tumoraux ont été mesurées en élastographie à l’aide de la technique « Shear Wave Elastography » (SWE). Afin de comprendre l’origine des modifications observées in vivo, des paramètres standard comme les niveaux de fibrose ou de nécrose ont été caractérisés ex vivo dans le tissu tumoral, grâce à l’immunohistochimie, une technique de référence

The application of advanced imaging techniques for the assessment of paediatric chest disease

Introduction – Cystic fibrosis (CF) and primary ciliary dyskinesia (PCD) both result in chronic suppurative lung disease with significant resulting morbidity and early mortality. Many clinical and academic groups advocate biennial or even annual CT surveillance from as early as 2 years of age, but new therapies and increasing life expectancy lead to concerns over the use of repeated CT imaging. There are many recent studies showing promise of MRI for structural lung imaging MRI based measures of lung function. Both CF and PCD result in multisystem disease and whilst much of the morbidity results from lung disease, monitoring of extrathoracic disease is likely also relevant. Aims and objectives – 1) To set up a clinically feasible, multisystem (lung, sinonasal and upper abdominal visceral) quantitative MRI examination for the investigation and follow up of CSLD 2) To evaluate novel imaging biomarkers of CF and PCD disease severity Hypotheses – 1) Combined structural and quantitative MRI assessment of the thorax can provide comparable information to CT such that follow up imaging via CT could be replaced with MRI. 2) Quantitative MR measures of ventilation correlate with established clinical measures of ventilation (LCI and FEV1) and provide additional spatial information. 3) A multisystem MRI assessment can provide new extra-thoracic imaging biomarkers of CF and PCD disease severity whilst being better tolerated by patients than current multimodality imaging follow up. Methods – People with CF or PCD referred for clinically indicated lung CT were prospectively recruited to undergo MR imaging of the lungs, liver and paranasal sinuses. Structural lung imaging was optimised for speed of acquisition using T2 BLADE imaging, in axial and coronal plane, during breath holds rather than more conventional respiratory triggering. Images were scored by two observers using the Eichinger scoring system and compared to CT structural scores using the CFCT scoring system. Lung T1 mapping was performed via free breathing IR-HASTE and T1 and T2 mapping performed via breath hold ufbSSFP imaging. Functional lung imaging was performed via pre and post hyperoxygenation ufbSSFP T1 mapping, free breathing dynamic oxygen enhanced IR-HASTE imaging (OE-MRI) and non-contrast ufbSSFP-based matrix pencil decomposition imaging of ventilation and pulmonary perfusion. Lung T1 maps included the superior portion of the liver enabling simultaneous liver T1 mapping. A multiparametric paranasal sinus protocol was devised containing structural (T1 and T2 TSE), susceptibility and diffusion weighted sequences for the calculation of sinus volume, mucus volume and mucosal volume, presence or absence of artefact associated with infective micro-organisms and calculation of mucus and mucosal diffusion. Participant tolerability of MR imaging assessed via a bespoke questionnaire, completed before and after both CT and MR imaging. Multiple breath wash-out testing was performed on the day of the MRI and spirometry, antibiotic usage, abdominal ultrasound and sheer wave elastography collected retrospectively from the electronic patient record. Results – 22 participants were recruited, all of whom completed the hour-long MRI protocol. The median age was 14 years (range 6 – 35). 2-plane structural lung imaging was acquired in a total of 2 minutes 4 seconds with only a single participant reporting difficulties with the required breath holds. Interclass Correlation Coefficients of interobserver variability in MRI scores were comparable to CT (0.877-0.965 compared to 0.877-0.989 respectively) suggesting good image quality with strong correlation between MR and CT component scores (bronchiectasis/bronchial wall thickening r=0.828,p<0.001; mucus plugging r=0.812, p<0.001; parenchymal score r=0.564 – 0.729, p<0.001 – 0.006). Median lung T1 did not correlate with clinical markers of disease severity, but median lung T2 demonstrated strong correlation with CT bronchial wall thickening (r=-0.655, p=0.001) and LCI2.5 (r=-0.540, p=0.046), most likely representing a surrogate of pulmonary perfusion (most pulmonary T2 signal likely originates from the pulmonary blood pool). Significant ufbSSFP enhancement was demonstrated post hyperoxygenation, but the degree of enhancement did not correlate significantly with clinical measures of disease severity. There was, however, very strong correlations between matrix pencil decomposition ventilation fraction and LCI2.5 (r=0.831, p=0.001) and CFCT scores (r= up to 0.731, p=<0.001). Significant correlation was also demonstrated between measures of ventilation heterogeneity (oxygen wash-out time skew and kurtosis) and both LCI2.5 (r=0.591, p=0.013) and CFCT component scores (r= up to 0.718, p<0.001). Liver T1 values did not correlate with evidence of liver disease on liver function tests or ultrasound imaging, but interpretation was severely limited by the very small number of recruits with CF liver disease. Sinus imaging was the last part of the protocol with failed analysis in only one patient from too much motion (a 6 year old). Association was demonstrated between exacerbation frequency and opacification of maxillary sinuses by mucusa (p=0.074), between CT hyperinflation score and increasing levels of mucus susceptibility artefact (0=0.028), between exacerbation frequency, CT bronchial wall thickening and mucus plugging and increased sinus mucus diffusion (r=0.581, p=0.048, r=0.744, p=0.006 and r=0.633, p=0.019 respectively) and between CT hyperinflation, bronchiectasis and bronchial wall thickening scores and increased sinus mucosal diffusion (r=-0.847, p=0.016; r=-0.542, p=0.017 and r=-0.427, p=0.069 respectively). A third of recruits stated that they would opt for MR imaging over CT imaging in the future and whilst 41% reported difficulties staying still for the MRI, respiratory image post processing was successful in all participants, with no parts of the MRI studies repeated. Conclusion – Multisystem lung, liver and sinus MRI is feasible, well tolerated by people with CF or PCD, down to the age of 6 years, and provides gross structural imaging of sufficient quality to replace CT for lung imaging surveillance. Furthermore, the addition of functional lung imaging provides quantitative outputs which correlate well with clinically established lung function tests with the benefit of spatially localised lung function and additional quantitative measures of relevant extrapulmonary disease, within a single ionising radiation free examination. The data from this study have supported funding for future work addressing short, medium and long-term repeatability and longitudinal trends both in times of disease stability and over the course of an infective exacerbation.Open Acces