Search

Objectives To evaluate changes in diaphragmatic function in Pompe disease using MRI over time, both during natural disease course and during treatment with enzyme replacement therapy (ERT). Methods In this prospective study, 30 adult Pompe patients and 10 healthy controls underwent pulmonary function tests and spirometry-controlled MRI twice, with an interval of 1 year. In the sagittal view of 3D gradient echo breath-hold acquisitions, diaphragmatic motion (cranial-caudal ratio between end-inspiration and end-expiration) and curvature (diaphragm height and area ratio) were calculated using a machine learning algorithm based on convolutional neural networks. Changes in outcomes after 1 year were compared between Pompe patients and healthy controls using the Mann-Whitney test. Results Pulmonary function outcomes and cranial-caudal ratio in Pompe patients did not change significantly over time compared to healthy controls. Diaphragm height ratio increased by 0.04 (−0.38 to 1.79) in Pompe patients compared to −0.02 (−0.18 to 0.25) in healthy controls (p = 0.02). An increased diaphragmatic curvature over time was observed in particular in untreated Pompe patients (p = 0.03), in those receiving ERT already for over 3 years (p = 0.03), and when severe diaphragmatic weakness was found on the initial MRI (p = 0.01); no progression was observed in Pompe patients who started ERT less than 3 years ago and in Pompe patients with mild diaphragmatic weakness on their initial MRI. Conclusions MRI enables to detect small changes in diaphragmatic curvature over 1-year time in Pompe patients. It also showed that once severe diaphragmatic weakness has occurred, improvement of diaphragmatic muscle function seems unlikely. Key Points • Changes in diaphragmatic curvature in Pompe patients over time assessed with 3D MRI may serve as an outcome measure to evaluate the effect of treatment on diaphragmatic function. • Diaphragmatic curvature showed a significant deterioration after 1 year in Pompe patients compared to healthy controls, but the curvature seems to remain stable over this period in patients who were treated with enzyme replacement therapy for less than 3 years, possibly indicating a positive effect of ERT. • Improvement of diaphragmatic curvature over time is rarely seen in Pompe patients once diaphragmatic motion shows severe impairment (cranial-caudal inspiratory/expiratory ratio < 1.4).

Background and objective: The most common respiratory complication of extreme prematurity is bronchopulmonary dysplasia(BPD), leading to structural lung changes and impaired respiratory outcomes. However, also extremely preterm children without BPD may show similar adverse respiratory outcomes. There is need for a safe imaging modality for preterm children with and without BPD for disease severity and risk stratification assessment. Our objective was to develop a chest Magnetic Resonance Imaging(MRI) protocol in preterm children with and without BPD at school age. Methods: Nine healthy volunteers (median age 11.6(range 8.8-12.8) years), eleven preterm children with BPD (11.0(7.2-15.6) years) and nine without BPD (11.1(10.7-12.6) years) underwent MRI. MR images were scored on hypo- and hyperintense abnormalities, bronchopathy and architectural distortion. MRI data were correlated to spirometry. Ventilation and perfusion defects were analysed using Fourier Decomposition (FD) MRI. Results: On MRI, children with BPD had a higher %diseased lung (9.1 (IQR 5.9-11.6)%) compared to preterm children without BPD (3.4 (IQR 2.5-5.4)%, p1 (r=-0.40, p=0.04), FEV1/FVC (r=-0.49, p=0.009) and FEF75 (r=-0.63, pConclusion: MRI can identify structural and functional lung damage at school age in preterm children with and without BPD, showing good correlation with spirometry. We propose chest MRI as a sensitive and safe imaging method (without ionising radiation, contrast agents or the use of anaesthesia) for the long-term follow up of preterm children.

Background Risk for infection and potential malignant degeneration are the most common arguments for resecting asymptomatic Congenital Pulmonary Airway Malformations (CPAM). We aimed to investigate if CT- imaging characteristics can be used to predict histopathological features, by using an objective quantitative CT scoring method. Methods Archival CPAM tissue samples were histologically re-assessed and patients who had a pre-operative volumetric CT-scan were included. Lung disease was quantified using the newly-developed congenital lung abnormality quantification(CLAQ) scoring method and obtained percentages were used to predict histopathological signs of inflammation and presence of mucinous proliferation (MP). Because MP is presumed a precursor for mucinous adenocarcinoma in situ (AIS) this method was also used to compare CT-scans of patients with AIS to those with only CPAM. Results Thirty-three CPAM patients were included of which 13(39%) had histological signs of inflammation and 8(24%) had a MP. Patients with inflammation had a significantly smaller lesion (14% vs 38%) while those with MP had more extensive disease (54%vs17%). Patients with AIS had a significantly smaller lesion compared to CPAM patients (5%vs29%). Significant predictors for inflammation were smaller lesion size and percentage hypodensity within lesions while a larger lesion size and percentage parenchymal hyperdensity (solid lung tissue components) were predictors for MP as well as AIS. Conclusions Smaller CPAM lesions may be more susceptible to inflammation while larger lesions may be associated with the presence of MP. Parenchymal hyperdensity is found as a predictor for MP as well as AIS and should therefore elicit more extensive gross sampling. Level of evidence Level III.

Congenital thoracic anomalies are uncommon malformations that require a precise diagnosis to guide parental counseling and possible prenatal treatment. Prenatal ultrasound (US) is the gold standard imaging modality to first detect and characterize these abnormalities and the best modality for follow-up. Fetal magnetic resonance imaging (MRI) is a complementary tool that provides multiplanar assessment and tissue characterization and can help estimate prognosis. Prenatal treatment is increasingly being used in fetuses with signs of distress and to potentially decrease morbidity and mortality. In this essay, the authors illustrate side-by-side US, MRI and therapeutic options for congenital thoracic anomalies in cases that presented to a tertiary pediatric hospital during the 7-year period 2014–2021. Entities included are congenital diaphragmatic hernia, congenital pulmonary airway malformation, bronchopulmonary sequestration, hybrid lesions, foregut duplications cysts and congenital lobar overinflation. Treatment options include maternal steroids, thoraco-amniotic shunt and fetal endotracheal occlusion. Recognition of typical findings in congenital thoracic anomalies is helpful to establish diagnosis, predict prognosis and plan perinatal treatment. Graphical Abstract

A new task force dedicated to artificial intelligence (AI) with respect to paediatric radiology was created in 2021 at the International Paediatric Radiology (IPR) meeting in Rome, Italy (a joint society meeting by the European Society of Pediatric Radiology [ESPR] and the Society for Pediatric Radiology [SPR]). The concept of a separate task force dedicated to AI was borne from an ESPR-led international survey of health care professionals’ opinions, expectations and concerns regarding AI integration within children’s imaging departments. In this survey, the majority (> 80%) of ESPR respondents supported the creation of a task force and helped define our key objectives. These include providing educational content about AI relevant for paediatric radiologists, brainstorming ideas for future projects and collaborating on AI-related studies with respect to collating data sets, de-identifying images and engaging in multi-case, multi-reader studies. This manuscript outlines the starting point of the ESPR AI task force and where we wish to go.

The aim of this exploratory study was to evaluate diaphragmatic function across various neuromuscular diseases using spirometry-controlled MRI. We measured motion of the diaphragm relative to that of the thoracic wall (cranial-caudal ratio vs. anterior posterior ratio; CC-AP ratio), and changes in the diaphragmatic curvature (diaphragm height and area ratio) during inspiration in 12 adults with a neuromuscular disease having signs of respiratory muscle weakness, 18 healthy controls, and 35 adult Pompe patients – a group with prominent diaphragmatic weakness. CC-AP ratio was lower in patients with myopathies (n=7, 1.25±0.30) and motor neuron diseases (n=5, 1.30±0.10) than in healthy controls (1.37±0.14; p=0.001 and p=0.008), but not as abnormal as in Pompe patients (1.12±0.18; p=0.011 and p=0.024). The mean diaphragm height ratio was 1.17±0.33 in patients with myopathies, pointing at an insufficient diaphragmatic contraction. This was also seen in patients with Pompe disease (1.28±0.36), but not in healthy controls (0.82±0.33) or patients with motor neuron disease (0.82±0.24). We conclude that spirometry-controlled MRI enables us to investigate respiratory dysfunction across neuromuscular diseases, suggesting that the diaphragm is affected in a different way in myopathies and motor neuron diseases. Whether MRI can also be used to evaluate progression of diaphragmatic dysfunction requires additional studies.

IntroductionConsensus is lacking on the optimal management of asymptomatic congenital pulmonary airway malformation (CPAM). For future studies, the CONNECT consortium (the COllaborative Neonatal Network for the first European CPAM Trial)—an international collaboration of specialised caregivers—has established consensus on a core outcome set of outcome parameters concerning respiratory insufficiency, surgical complications, mass effect and multifocal disease. These outcome parameters have been incorporated in the CONNECT trial, a randomised controlled trial which, in order to develop evidence-based practice, aims to compare conservative and surgical management of patients with an asymptomatic CPAM.Methods and analysisChildren are eligible for inclusion after the CPAM diagnosis has been confirmed on postnatal chest CT scan and they remain asymptomatic. On inclusion, children are randomised to receive either conservative or surgical management. Subsequently, children in both groups are enrolled into a standardised, 5-year follow-up programme with three visits, including a repeat chest CT scan at 2.5 years and a standardised exercise tolerance test at 5 years.The primary outcome is exercise tolerance at age 5 years, measured according to the Bruce treadmill protocol. Secondary outcome measures are molecular genetic diagnostics, validated questionnaires—on parental anxiety, quality of life and healthcare consumption—, repeated imaging and pulmonary morbidity during follow-up, as well as surgical complications and histopathology. This trial aims to end the continuous debate surrounding the optimal management of asymptomatic CPAM.Ethics and disseminationThis study is being conducted in accordance with the Declaration of Helsinki. The Medical Ethics Review Board of Erasmus University Medical Centre Rotterdam, The Netherlands, has approved this protocol (MEC-2022–0441). Results will be disseminated through peer-reviewed scientific journals and conference presentations.Trial registration numberNCT05701514.

OBJECTIVES When surgical resection is indicated for a congenital lung abnormality (CLA), lobectomy is often preferred over segmentectomy, mostly because the latter is associated with more residual disease. Presumably, this occurs in children because sublobar surgery often does not adhere to anatomical borders (wedge resection instead of segmentectomy), thus increasing the risk of residual disease. This study investigated the feasibility of identifying eligible cases for anatomical segmentectomy by combining virtual reality (VR) and artificial intelligence (AI). METHODS Semi-automated segmentation of bronchovascular structures and lesions were visualized with VR and AI technology. Two specialists independently evaluated via a questionnaire the informative value of regular computed tomography versus three-dimensional (3D) VR images. RESULTS Five asymptomatic, non-operated cases were selected. Bronchovascular segmentation, volume calculation and image visualization in the VR environment were successful in all cases. Based on the computed tomography images, assignment of the CLA lesion to specific lung segments matched between the consulted specialists in only 1 out of the cases. Based on the three 3D VR images, however, the localization matched in 3 of the 5 cases. If the patients would have been operated, adding the 3D VR tool to the preoperative workup would have resulted in changing the surgical strategy (i.e. lobectomy versus segmentectomy) in 4 cases. CONCLUSIONS This study demonstrated the technical feasibility of a hybridized AI–VR visualization of segment-level lung anatomy in patients with CLA. Further exploration of the value of 3D VR in identifying eligible cases for anatomical segmentectomy is therefore warranted.

Imaging speed, spatial resolution and availability have made CT the favored cross-sectional imaging modality for evaluating various respiratory diseases of children - but only for the price of a radiation exposure. MRI is increasingly being appreciated as an alternative to CT, not only for offering three-dimensional (3-D) imaging without radiation exposure at only slightly inferior spatial resolution, but also for its superior soft-tissue contrast and exclusive morpho-functional imaging capacities beyond the scope of CT. Continuing technical improvements and experience with this so far under-utilized modality contribute to a growing acceptance of MRI for an increasing number of indications, in particular for pediatric patients. This review article provides the reader with practical easy-to-use protocols for common clinical indications in children. This is intended to encourage pediatric radiologists to appreciate the new horizons for applications of this rapidly evolving technique in the field of pediatric respiratory diseases.

Objectives To develop a clinical guideline for structured assessment and uniform reporting of congenital lung abnormalities (CLA) on Computed Tomography (CT)-scans. Materials and Methods A systematic literature search was conducted for articles describing CT-scan abnormalities of congenital pulmonary airway malformation (CPAM), bronchopulmonary sequestration (BPS), congenital lobar emphysema (CLE) and bronchogenic cyst (BC). A structured report using objective features of CLA was developed after consensus between a pediatric pulmonologist, radiologist and surgeon. Results Of 1581 articles identified, 158 remained after title-abstract screening by two independent reviewers. After assessing full-texts, we included 28 retrospective cohort-studies. Air-containing cysts and soft tissue masses are described in both CPAM and BPS while anomalous arterial blood supply is only found in BPS. Perilesional low-attenuation areas, atelectasis and mediastinal shift may be found in all aforementioned abnormalities and can also be seen in CLE as a cause of a hyperinflated lobe. We have developed a structured report, subdivided into five sections: Location & Extent, Airway, Lesion, Vascularization and Surrounding tissue. Conclusions CT-imaging findings in CLA are broad and nomenclature is variable. Overlap is seen between and within abnormalities, possibly due to definitions often being based on pathological findings, which is an unsuitable approach for CT imaging. We propose a structured assessment of CLA using objective radiological features and uniform nomenclature to improve reporting.

BackgroundIn Pompe disease, an inherited metabolic muscle disorder, severe diaphragmatic weakness often occurs. Enzyme replacement treatment is relatively ineffective for respiratory function, possibly because of irreversible damage to the diaphragm early in the disease course. Mildly impaired diaphragmatic function may not be recognized by spirometry, which is commonly used to study respiratory function. In this cross-sectional study, we aimed to identify early signs of diaphragmatic weakness in Pompe patients using chest MRI.MethodsPompe patients covering the spectrum of disease severity, and sex and age matched healthy controls were prospectively included and studied using spirometry-controlled sagittal MR images of both mid-hemidiaphragms during forced inspiration. The motions of the diaphragm and thoracic wall were evaluated by measuring thoracic cranial-caudal and anterior–posterior distance ratios between inspiration and expiration. The diaphragm shape was evaluated by measuring the height of the diaphragm curvature. We used multiple linear regression analysis to compare different groups.ResultsWe included 22 Pompe patients with decreased spirometry results (forced vital capacity in supine position p p = 0.001), indicating an increased curvature of the diaphragm during inspiration in Pompe patients.ConclusionsEven in early-stage Pompe disease, when spirometry results are still within normal range, the motion of the diaphragm is already reduced and the shape is more curved during inspiration. MRI can be used to detect early signs of diaphragmatic weakness in patients with Pompe disease, which might help to select patients for early intervention to prevent possible irreversible damage to the diaphragm.

Imaging plays a pivotal role in the noninvasive assessment of cystic fibrosis (CF)-related lung damage, which remains the main cause of morbidity and mortality in children with CF. The development of new imaging techniques has significantly changed clinical practice, and advances in therapies have posed diagnostic and monitoring challenges. The authors summarise these challenges and offer new perspectives in the use of imaging for children with CF for both clinicians and radiologists. This article focuses on chest radiography and CT, which are the two main radiologic techniques used in most cystic fibrosis centres. Advantages and disadvantages of radiography and CT for imaging in CF are described, with attention to new developments in these techniques, such as the use of artificial intelligence (AI) image analysis strategies to improve the sensitivity of radiography and CT and the introduction of the photon-counting detector CT scanner to increase spatial resolution at no dose expense.

RationalePaediatric laryngotracheal stenosis (LTS) is often successfully corrected with open airway surgery. However, respiratory and vocal sequelae frequently remain. Clinical care and surgical interventions could be improved with better understanding of these sequelae.ObjectiveThe objective of this cross-sectional study was to develop an upper airway MRI protocol to obtain information on anatomical and functional sequelae post-LTS repair.MethodsForty-eight patients (age 14.4 (range 7.5–30.7) years) and 11 healthy volunteers (15.9 (8.2–28.8) years) were included. Spirometry and static and dynamic upper airway MRI (3.0 T, 30 min protocol) were conducted. Analysis included assessment of postoperative anatomy and airway lumen measurements during static and dynamic (inspiration and phonation) acquisitions.Main resultsGood image quality without artefacts was achieved for static and dynamic images in the majority of MRIs. MRI showed vocal cord thickening in 80.9% of patients and compared with volunteers, a significant decrease in vocal cord lumen area (22.0 (IQR 17.7–30.3) mm2 vs 35.1 (21.2–54.7) mm2, p=0.03) but not cricoid lumen area (62.3±27.0 mm2 vs 66.2±34.8 mm2, p=0.70). Furthermore, 53.2% of patients had an A-frame deformation at site of previous tracheal cannula, showing lumen collapse during inspiration. Dynamic imaging showed incomplete vocal cord abduction during inspiration in 42.6% and incomplete adduction during phonation in 61.7% of patients.ConclusionsStatic and dynamic MRI is an excellent modality to non-invasively image anatomy, tissue characteristics and vocal cord dynamics of the upper airways. MRI-derived knowledge on postsurgical LTS sequelae might be used to improve surgery.

Introduction To date, no consensus has been reached on the optimal management of congenital lung abnormalities, and factors predicting postnatal outcome have not been identified. We developed an objective quantitative computed tomography (CT) scoring method, and assessed its value for clinical decision‐making. Methods Volumetric CT‐scans of all patients born with a congenital lung abnormality between January 1999 and 2018 were assessed. Lung disease was quantified using the newly‐developed congenital lung abnormality quantification (CLAQ) scoring method. In 20 equidistant axial slices, cells of a square grid were scored according to the abnormality within. The scored CT parameters were used to predict development of symptoms, and SD scores for spirometry and exercise tolerance (Bruce treadmill test) at 8 years of age. Results CT‐scans of 124 patients with a median age of 5 months were scored. Clinical diagnoses included congenital pulmonary airway malformation (49%), bronchopulmonary sequestration (27%), congenital lobar overinflation (22%), and bronchogenic cyst (1%). Forty‐four patients (35%) developed symptoms requiring surgery of whom 28 (22%) patients became symptomatic before a CT‐scan was scheduled. Lesional hyperdensity was found as an important predictor of symptom development and decreased exercise tolerance. Using receiver operating characteristic analysis, an optimal cut‐off value for developing symptoms was found at 18% total disease. Conclusion CT‐quantification of congenital lung abnormalities using the CLAQ method is an objective and reproducible system to describe congenital lung abnormalities on chest CT. The risk for developing symptoms may increase when more than a single lung lobe is affected.

Cystic pancreatic lesions (CPLs) are frequently casual findings in radiological examinations performed for other reasons in patients with unrelated symptoms. As they require different management according to their histological nature, differential diagnosis is essential. Radiologist plays a key role in the diagnosis and management of these lesions as imaging is able to correctly characterize most of them and thus address to a correct management. The first step for a correct characterization is to look for a communication between the CPLs and the main pancreatic duct, and then, it is essential to evaluate the morphology of the lesions. Age, sex and a history of previous pancreatic pathologies are important information to be used in the differential diagnosis. As some CPLs with different pathologic backgrounds can show the same morphological findings, differential diagnosis can be difficult, and thus, the final diagnosis can require other techniques, such as endoscopic ultrasound, endoscopic ultrasound-fine needle aspiration and endoscopic ultrasound-through the needle biopsy, and multidisciplinary management is important for a correct management.

Background: Magnetic Resonance Imaging (MRI) techniques to image the larynx have evolved rapidly into a promising and safe imaging modality, without need for sedation or ionizing radiation. MRI is therefore of great interest to image pediatric laryngeal diseases. Our aim was to review MRI developments relevant for the pediatric larynx and to discuss future imaging options. Methods: A systematic search was conducted to identify all morphological and diagnostic studies in which MRI was used to image the pediatric larynx, laryngeal disease, or vocal cords. Results: Fourteen articles were included: three studies on anatomical imaging of the larynx, two studies on Diffusion Weighted Imaging, four studies on vocal cord imaging and five studies on the effect of anaesthesiology on the pediatric larynx. MRI has been used for pediatric laryngeal imaging since 1991. MRI provides excellent soft tissue contrast and good visualization of vascular diseases such as haemangiomas. However, visualization of cartilaginous structures, with varying ossification during childhood, and tissue differentiation remain challenging. The latter has been partly overcome with diffusion weighted imaging (DWI), differentiating between benign and malignant masses with excellent sensitivity (94-94.4%) and specificity (91.2-100%). Vocal cord imaging evolved from static images focused on vocal tract growth to dynamic images able to detect abnormal vocal cord movement. Conclusion: MRI is promising to evaluate the pediatric larynx, but studies using MRI as diagnostic imaging modality are scarce. New static and dynamic MR imaging techniques could be implemented in the pediatric population. Further research on imaging of pediatric laryngeal diseases should be conducted.

Purpose The purpose of this study is to evaluate the influence of different field strengths on perfusion and ventilation parameters, SNR and CNR derived by PREFUL MRI using predefined sequence parameters. Methods Data sets of free breathing 2d FLASH lung MRI were acquired from 15 healthy subjects at 1.5T and 3T (Magnetom Avanto and Skyra, Siemens Healthcare, Erlangen, Germany) with a maximum period of 3 days in between. The processed functional parameters regional ventilation (RVent), perfusion (Q), quantified perfusion (QQuant), perfusion defect percentage (QDP), ventilation defect percentage (VDP) and ventilation-perfusion match (VQM) were compared for systematic differences. Signal- and contrast-to-noise ratio (SNR and CNR) of both acquisitions were analyzed. Results RVent, Q, VDP, SNR and CNR presented no significant differences between 1.5T and 3T. QQuant (1.5T vs. 3T, P = 0.04), and QDP (1.5T vs. 3T, P≤0.01) decreased significantly at 3T. Consequently, VQM increased significantly (1.5T vs. 3T, P≤0.01). Skewness and kurtosis of the Q-values increased significantly at 3T (P≤0.01). The mean Sørensen-Dice coefficients between both series were 0.91 for QDP and 0.94 for VDP. The Bland-Altman analysis of both series showed mean differences of 4.29% for QDP, 1.23% for VDP and -5.15% for VQM. Using the above-mentioned parameters for three-day repeatability at two different scanners and field strengths, the retrospective power calculation showed, that a sample size of 15 can detect differences of 3.7% for QDP, of 2.9% for VDP and differences of 2.6% for VQM. Conclusion Significant differences in QDP may be related to field inhomogeneities, which is expressed by increasing skewness and kurtosis at 3T. QQuant reveals only poor reproducibility between 1.5T and 3T. RVent, Q, VDP, SNR and CNR were not altered significantly at the used sequence parameters. Healthy participants with minimal defects present high spatial agreement of QDP and VDP.

Diagnosis of bronchiectasis is usually made using chest computed tomography (CT) scan, the current gold standard method. A bronchiectatic airway can show abnormal widening and thickening of its airway wall. In addition, it can show an irregular wall and lack of tapering, and/or can be visible in the periphery of the lung. Its diagnosis is still largely expert based. More recently, it has become clear that airway dimensions on CT and therefore the diagnosis of bronchiectasis are highly dependent on lung volume. Hence, control of lung volume is required during CT acquisition to standardise the evaluation of airways. Automated image analysis systems are in development for the objective analysis of airway dimensions and for the diagnosis of bronchiectasis. To use these systems, clear and objective definitions for the diagnosis of bronchiectasis are needed. Furthermore, the use of these systems requires standardisation of CT protocols and of lung volume during chest CT acquisition. In addition, sex- and age-specific reference values are needed for image analysis outcome parameters. This review focusses on today's issues relating to the radiological diagnosis of bronchiectasis using state-of-the-art CT imaging techniques.

Disorders of the lungs and pleura are common in children and are a frequent indication for medical imaging. Over the past decade, a combination of advances in MR imaging scanner technology and increased concern about the effects of ionizing radiation has led to increased utilization of MR imaging in the pediatric population. Despite this general trend, there has been slower adoption of MR imaging to evaluate the lungs and pleura due to technical limitations including motion artifact, low signal-to-noise ratios, and signal dephasing at air-tissue interfaces. As MR imaging technology advances, many of these technical hurdles are being overcome, and MR imaging of the lungs and pleura has begun to be a feasible option for many pediatric pleuropulmonary conditions. Therefore, an up-to-date understanding of these emerging applications is important to practitioners performing MR imaging in infants and children. In this chapter, an overview of MR imaging techniques to evaluate the lungs and pleura in children is discussed. Normal anatomy and development of the lungs and pleura are described, and the MR imaging findings in a spectrum pediatric lung and pleural disease are illustrated.

Objectives This study was conducted in order to evaluate the effect of geometric distortion (GD) on MRI lung volume quantification and evaluate available manual, semi-automated, and fully automated methods for lung segmentation. Methods A phantom was scanned with MRI and CT. GD was quantified as the difference in phantom’s volume between MRI and CT, with CT as gold standard. Dice scores were used to measure overlap in shapes. Furthermore, 11 subjects from a prospective population-based cohort study each underwent four chest MRI acquisitions. The resulting 44 MRI scans with 2D and 3D Gradwarp were used to test five segmentation methods. Intraclass correlation coefficient, Bland–Altman plots, Wilcoxon, Mann–Whitney U, and paired t tests were used for statistics. Results Using phantoms, volume differences between CT and MRI varied according to MRI positions and 2D and 3D Gradwarp correction. With the phantom located at the isocenter, MRI overestimated the volume relative to CT by 5.56 ± 1.16 to 6.99 ± 0.22% with body and torso coils, respectively. Higher Dice scores and smaller intraobject differences were found for 3D Gradwarp MR images. In subjects, semi-automated and fully automated segmentation tools showed high agreement with manual segmentations (ICC = 0.971–0.993 for end-inspiratory scans; ICC = 0.992–0.995 for end-expiratory scans). Manual segmentation time per scan was approximately 3–4 h and 2–3 min for fully automated methods. Conclusions Volume overestimation of MRI due to GD can be quantified. Semi-automated and fully automated segmentation methods allow accurate, reproducible, and fast lung volume quantification. Chest MRI can be a valid radiation-free imaging modality for lung segmentation and volume quantification in large cohort studies. Key Points • Geometric distortion varies according to MRI setting and patient positioning. • Automated segmentation methods allow fast and accurate lung volume quantification. • MRI is a valid radiation-free alternative to CT for quantitative data analysis. Electronic supplementary material The online version of this article (10.1007/s00330-018-5863-7) contains supplementary material, which is available to authorized users.

Thin-slices multi-detector computed tomography (MDCT) plays a key role in the differential diagnosis of interstitial lung disease (ILD). However, thin-slices MDCT has a limited ability to detect active inflammation, which is an important target of newly developed ILD drug therapy. Magnetic resonance imaging (MRI), thanks to its multi-parameter capability, provides better tissue characterisation than thin-slices MDCT.Our aim was to summarise the current status of MRI applications in ILD and to propose an ILD-MRI protocol. A systematic literature search was conducted for relevant studies on chest MRI in patients with ILD.We retrieved 1246 papers of which 55 original papers were selected for the review. We identified 24 studies comparing image quality of thin-slices MDCT and MRI using several MRI sequences. These studies described new MRI sequences to assess ILD parenchymal abnormalities, such as honeycombing, reticulation and ground-glass opacity. Thin-slices MDCT remains superior to MRI for morphological imaging. However, recent studies with ultra-short echo-time MRI showed image quality comparable to thin-slices MDCT. Several studies demonstrated the added value of chest MRI by using functional imaging, especially to detect and quantify inflammatory changes.We concluded that chest MRI could play a role in ILD patients to differentiate inflammatory and fibrotic changes and to assess efficacy of new ILD drugs.

For cystic fibrosis (CF) patients older than 6 years there are convincing data that suggest respiratory tract exacerbations (RTE) play an important role in the progressive loss of functional lung tissue. There is a poor understanding of the pathobiology of RTE and whether specific treatment of RTE reduces lung damage in the long term. In addition, there are limited tools available to measure the various components of CF lung disease and responses to therapy. Therefore, in order to better understand the impact of RTE on CF lung disease we need to develop sensitive measures to characterize RTE and responses to treatment; and improve our understanding of structure-function changes during treatment of RTE. In this paper we review our current knowledge of the impact of RTE on the progression of lung disease and identify strategies to improve our understanding of the pathobiology of RTE. By improving our knowledge regarding RTE in CF we will be better positioned to develop approaches to treatment that are individualized and that can prevent permanent structural damage. We suggest the development of a ventilation, perfusion, inflammation and structure (VIPS)-MRI suite that supplies the clinician with data on ventilation, inflammation, perfusion, and structure in one MRI session. VIPS-MRI could be an important step to better understand the factors that contribute to and limit treatment efficacy of RTE.

The aim was to investigate whether diffusion-weighted magnetic resonance imaging (DWI) detects and monitors inflammatory and lung function changes during respiratory tract exacerbations (RTE) treatment in patients with cystic fibrosis (CF).29 patients with RTE underwent DWI pre- and post-antibiotic treatment. A control group of 27 stable patients, matched for age and sex, underwent DWI with the same time gap as those undergoing RTE treatment. Clinical status and lung function were assessed at each DWI time point. The CF-MRI scoring system was used to assess structural lung changes in both CF groups.Significant reduction in the DWI score over the course of antibiotic treatment (pDWI is a promising imaging method for noninvasive detection of pulmonary inflammation during RTE, and may be used to monitor treatment efficacy of anti-inflammatory treatment.

Acute pulmonary exacerbations (aPEs) in patients with cystic fibrosis (CF) often result in incomplete recovery of lung function despite treatment, and are associated with lung function decline over time [1, 2]. Monitoring is therefore important to detect aPEs early and to track treatment responses. Recent studies testing pulmonary function with multiple breath washout (MBW) have shown that the lung clearance index (LCI), the main outcome measure of MBW, is a sensitive tool to measure early changes in the CF lung [3, 4]. However, the potential role of MBW and LCI in more advanced CF lung disease is currently unclear. In fact, a recent study demonstrated heterogeneous responses in LCI, with a significant proportion of patients with CF showing worsening of LCI with treatment for aPEs [5]. Resolution of mucus plugging, resulting in recruitment of poorly ventilated areas of the lung to MBW, would potentially explain the discordant changes in pulmonary function testing by spirometry and LCI with treatment., Resolution of mucus plugging may explain worsening LCI during pulmonary exacerbation treatment in children with CF http://ow.ly/LTLm30dp6hS

In this work, a framework for fully automated lung extraction from magnetic resonance imaging (MRI) inspiratory data that have been acquired within a on-going epidemiological child cohort study is presented. The method's main steps are intensity inhomogeneity correction, denoising, clustering, airway extraction and lung region refinement. The presented approach produces highly accurate results (Dice coefficients ≤ 95%), when compared to semi-Automatically obtained masks, and has potential to be applied to the whole study data.

Tracheobronchomalacia (TBM) is defined as an excessive collapse of the intrathoracic trachea. Bronchoscopy is the gold standard for diagnosing TBM; however it has major disadvantages, such as general anaesthesia. Cine computed tomography (CT) is a noninvasive alternative used to diagnose TBM, but its use in children is restricted by ionising radiation. Our aim was to evaluate the feasibility of spirometer-controlled cine magnetic resonance imaging (MRI) as an alternative to cine-CT in a retrospective study. 12 children with a mean age (range) of 12 years (7-17 years), suspected of having TBM, underwent cine-MRI. Static scans were acquired at end-inspiration and expiration covering the thorax using a three-dimensional spoiled gradient echo sequence. Three-dimensional dynamic scans were performed covering only the central airways. TBM was defined as a decrease of the trachea or bronchi diameter >50% at end-expiration in the static and dynamic scans. The success rate of the cine-MRI protocol was 92%. Cine-MRI was compared with bronchoscopy or chest CT in seven subjects. TBM was diagnosed by cine-MRI in seven (58%) out of 12 children and was confirmed by bronchoscopy or CT. In four patients, cine-MRI demonstrated tracheal narrowing that was not present in the static scans. Spirometer controlled cine-MRI is a promising technique to assess TBM in children and has the potential to replace bronchoscopy.

Computed tomography (CT) is a sensitive technique to monitor structural changes related to cystic fibrosis (CF) lung disease. It detects structural pulmonary abnormalities such as bronchiectasis and trapped air, at an early stage, before they become apparent with other diagnostic tests. Clinical decisions may be influenced by knowledge of these abnormalities. CT imaging, however, comes with risk related to ionizing radiation exposure. The aim of this review is to discuss the risk of routine CT imaging in patients with CF, using current models of radiation-induced cancer, and to put this risk in perspective with other medical and nonmedical risks. The magnitude of the risk is a complex, controversial matter. Risk analyses have largely been based on a linear no-threshold model, and excess relative and excess absolute risk estimates have been derived mainly from atomic bomb survivors. The estimates have large confidence intervals. Our risk estimates are in concordance with previously reported estimates. A la...

BACKGROUND: Diaphragm weakness is the main reason for respiratory dysfunction in patients with Pompe disease, a progressive metabolic myopathy affecting respiratory and limb-girdle muscles. Since respiratory failure is the major cause of death among adult patients, early identification of respiratory muscle involvement is necessary to initiate treatment in time and possibly prevent irreversible damage. In this paper we investigate the suitability of dynamic MR imaging in combination with state-of-the-art image analysis methods to assess respiratory muscle weakness.METHODS: The proposed methodology relies on image registration and lung surface extraction to quantify lung kinematics during breathing. This allows for the extraction of geometry and motion features of the lung that characterize the independent contribution of the diaphragm and the thoracic muscles to the respiratory cycle.RESULTS: Results in 16 3D+t MRI scans (10 Pompe patients and 6 controls) of a slow expiratory maneuver show that kinematic analysis from dynamic 3D images reveals important additional information about diaphragm mechanics and respiratory muscle involvement when compared to conventional pulmonary function tests. Pompe patients with severely reduced pulmonary function showed severe diaphragm weakness presented by minimal motion of the diaphragm. In patients with moderately reduced pulmonary function, cranial displacement of posterior diaphragm parts was reduced and the diaphragm dome was oriented more horizontally at full inspiration compared to healthy controls.CONCLUSION: Dynamic 3D MRI provides data for analyzing the contribution of both diaphragm and thoracic muscles independently. The proposed image analysis method has the potential to detect less severe diaphragm weakness and could thus be used to determine the optimal start of treatment in adult patients with Pompe disease in prospect of increased treatment response.

Background Mucopolysaccharidosis type II (MPSII) patients frequently suffer from dyspnoea caused by restrictive airway disease due to skeletal abnormalities as well as glycosaminoglycans (GAG) accumulation at different levels of the airway, including the trachea. In this study we describe the extent of the tracheal and bronchial narrowing, the changes in airway diameter during respiration and the effects of these obstructions on respiratory function in adult MPSII patients. Methods Five adult MPSII patients (mean age 40 years) were included. Pulmonary function tests and in- and expiratory chest CT scans were obtained. Cross-sectional areas of trachea and main bronchi were measured at end-inspiration and -expiration and percentage collapse was calculated. Results There was diffuse narrowing of the entire intra-thoracic trachea and main bronchi and severe expiratory collapse of the trachea in all patients. At 1 cm above the aortic arch the median % collapse of the trachea was 68 (range 60 to 77 %), at the level of the aortic arch 64 (range 21–93 %), for the main bronchi this was 58 (range 26–66 %) on the left and 44 (range 9–76 %) on the right side. The pulmonary function tests showed that this airway collapse results in obstructive airway disease in all patients, which was severe (forced expiratory volume

Background Pompe disease is a progressive metabolic myopathy. Involvement of respiratory muscles leads to progressive pulmonary dysfunction, particularly in supine position. Diaphragmatic weakness is considered to be the most important component. Standard spirometry is to some extent indicative but provides too little insight into diaphragmatic dynamics. We used lung MRI to study diaphragmatic and chest-wall movements in Pompe disease. Methods In ten adult Pompe patients and six volunteers, we acquired two static spirometer-controlled MRI scans during maximum inspiration and expiration. Images were manually segmented. After normalization for lung size, changes in lung dimensions between inspiration and expiration were used for analysis; normalization was based on the cranial-caudal length ratio (representing vertical diaphragmatic displacement), and the anterior-posterior and left-right length ratios (representing chest-wall movements due to thoracic muscles). Results We observed striking dysfunction of the diaphragm in Pompe patients; in some patients the diaphragm did not show any displacement. Patients had smaller cranial-caudal length ratios than volunteers (p

Severe pulmonary dysfunction is a serious threat to patients with Pompe disease, a treatable metabolic neuromuscular disorder caused by lysosomal acid alpha glucosidase defi ciency. This pulmonary dysfunction – which is particularly severe in the supine position – is mainly caused by diaphragmatic weakness. Standard pulmonary function tests only provide indirect information about diaphragmatic function, and they do not supply information about chest mechanics in detail. We therefore used cine-MRI to examine the dynamic performance of respiratory muscles, and compared these data with the results of simultaneously performed pulmonary function testing.

Pediatric chest MRI is challenging. High-resolution scans of the lungs and airways are compromised by long imaging times, low lung proton density and motion. Low signal is a problem of normal lung. Lung abnormalities commonly cause increased signal intenstities. Among the most important factors for a successful MRI is patient cooperation, so the long acquisition times make patient preparation crucial. Children usually have problems with long breath-holds and with the concept of quiet breathing. Young children are even more challenging because of higher cardiac and respiratory rates giving motion blurring. For these reasons, CT has often been preferred over MRI for chest pediatric imaging. Despite its drawbacks, MRI also has advantages over CT, which justifies its further development and clinical use. The most important advantage is the absence of ionizing radiation, which allows frequent scanning for short- and long-term follow-up studies of chronic diseases. Moreover, MRI allows assessment of functional aspects of the chest, such as lung perfusion and ventilation, or airways and diaphragm mechanics. In this review, we describe the most common MRI acquisition techniques on the verge of clinical translation, their problems and the possible solutions to make chest MRI feasible in children.