A synthetic lung model (ASYLUM) for validation of functional lung imaging methods shows significant differences between signal-based and deformation-field-based ventilation measurements.

Introduction: Validation of functional free-breathing MRI involves a comparison to more established or more direct measurements. This procedure is cost-intensive, as it requires access to patient cohorts, lengthy protocols, expenses for consumables, and binds working time. Therefore, the purpose of this study is to introduce a synthetic lung model (ASYLUM), which mimics dynamic MRI acquisition and includes predefined lung abnormalities for an alternative validation approach.

Regional Pulmonary Morphology and Function: Photon-counting CT Assessment.

Background Experience with functional CT in the lungs without additional equipment in clinical routine is limited. Purpose To report initial experience and evaluate the robustness of a modified chest CT protocol and photon-counting CT (PCCT) for comprehensive analysis of pulmonary vasculature, perfusion, ventilation, and morphologic structure in a single examination. Materials and Methods In this retrospective study, consecutive patients with clinically indicated CT for various known and unknown pulmonary function impairment (six subgroups) were included between November 2021 and June 2022.

Increased regional ventilation as early imaging marker for future disease progression of interstitial lung disease: a feasibility study.

Objectives: Idiopathic pulmonary fibrosis (IPF) is a disease with a poor prognosis and a highly variable course. Pathologically increased ventilation-accessible by functional CT-is discussed as a potential predecessor of lung fibrosis. The purpose of this feasibility study was to investigate whether increased regional ventilation at baseline CT and morphological changes in the follow-up CT suggestive for fibrosis indeed occur in spatial correspondence.

Quantification of dual-energy CT-derived functional parameters as potential imaging markers for progression of idiopathic pulmonary fibrosis.

Objectives: The individual course of disease in idiopathic pulmonary fibrosis (IPF) is highly variable. Assessment of disease activity and prospective estimation of disease progression might have the potential to improve therapy management and indicate the onset of treatment at an earlier stage. The aim of this study was to evaluate whether regional ventilation, lung perfusion, and late enhancement can serve as early imaging markers for disease progression in patients with IPF.

[Radiological features of interstitial lung diseases].

In addition to pneumology and pathology, radiology is an essential discipline in the interdisciplinary diagnosis of interstitial lung diseases (ILDs). The gold standard for diagnosis of ILD is computed tomography. Diagnostic findings are based on specific radiological signs such as interlobular septal thickening and nodular changes.

Clinical Molecular Imaging of Pulmonary CXCR4 Expression to Predict Outcome of Pirfenidone Treatment in Idiopathic Pulmonary Fibrosis.

Background: Idiopathic pulmonary fibrosis (IPF) is a progressive disease for which two antifibrotic drugs recently were approved. However, an unmet need exists to predict responses to antifibrotic treatment, such as pirfenidone. Recent data suggest that upregulated expression of CXCR4 is indicative of outcomes in IPF.

Morphological and molecular motifs of fibrosing pulmonary injury patterns.

Interstitial lung diseases encompass a large number of entities, which are characterised by a small number of partially overlapping fibrosing injury patterns, either alone or in combination. Thus, the presently applied morphological diagnostic criteria do not reliably discriminate different interstitial lung diseases. We therefore analysed critical regulatory pathways and signalling molecules involved in pulmonary remodelling with regard to their diagnostic suitability.

Complications of CT-guided lung biopsy with a non-coaxial semi-automated 18 gauge biopsy system: Frequency, severity and risk factors.

Objectives: To evaluate frequency and severity of complications after CT-guided lung biopsy using the Society of Interventional Radiology (SIR) classification, and to assess risk factors for overall and major complications.

Materials And Methods: 311 consecutive biopsies with a non-coaxial semi-automated 18 gauge biopsy system were retrospectively evaluated. Complications after biopsy were classified into minor SIR1-2 and major SIR3-6.

Comprehensive three-dimensional morphology of neoangiogenesis in pulmonary veno-occlusive disease and pulmonary capillary hemangiomatosis.

Pulmonary veno-occlusive disease (PVOD) is a rare lung disease characterized by fibrotic narrowing of pulmonary veins leading to pulmonary hypertension (PH) and finally to death by right heart failure. PVOD is often accompanied by pulmonary capillary hemangiomatosis (PCH), a marked abnormal proliferation of pulmonary capillaries. Both morphological patterns often occur together and are thought to be distinct manifestations of the same disease process and accordingly are classified together in group 1' of the Nice classification of PH.

Parametric response mapping cut-off values that predict survival of hepatocellular carcinoma patients after TACE.

Purpose: Parametric response mapping (PRM) is a novel image-analysis technique applicable to assess tumor viability and predict intrahepatic recurrence of hepatocellular carcinoma (HCC) patients treated with transarterial chemoembolization (TACE). However, to date, the prognostic value of PRM for prediction of overall survival in HCC patients undergoing TACE is unclear. The objective of this explorative, single-center study was to identify cut-off values for voxel-specific PRM parameters that predict the post TACE overall survival in HCC patients.

Computed tomography in adult patients with primary ciliary dyskinesia: Typical imaging findings.

Objectives: Among patients with non-cystic fibrosis bronchiectasis, 1-18% have an underlying diagnosis of primary ciliary dyskinesia (PCD) and it is suspected that there is under-recognition of this disease. Our intention was to evaluate the specific features of PCD seen on computed tomography (CT) in the cohort of bronchiectasis in order to facilitate the diagnosis.

Materials And Methods: One hundred and twenty-one CTs performed in patients with bronchiectasis were scored for the involvement, type, and lobar distribution of bronchiectasis, bronchial dilatation, and bronchial wall thickening.

CT at onset of chronic lung allograft dysfunction in lung transplant patients predicts development of the restrictive phenotype and survival.

Purpose: To describe early signs for restrictive subtype of chronic lung allograft dysfunction (CLAD) after lung transplantation in computed tomography (CT) and to evaluate the predictive value for disease progression and survival.

Material And Methods: 52 CT examinations in lung transplant patients at CLAD onset were scored for CT features referring to airways disease, parenchymal or pleural abnormality. Patients with and without later development of restrictive CLAD (TLC≤80%) were compared.

Parametric response mapping of contrast-enhanced biphasic CT for evaluating tumour viability of hepatocellular carcinoma after TACE.

Objectives: To determine the feasibility and role of parametric response mapping (PRM) for quantitative assessment of regional contrast-enhancement patterns in hepatocellular carcinoma (HCC).

Methods: Biphasic CT of 19 patients receiving repetitive conventional transarterial chemoembolisation (cTACE) for intermediate stage HCC were retrospectively analysed at baseline and follow-up at 3, 6, and 9 months. Voxel-based registration of arterial and porto-venous phases, with segmentation of the largest target lesion was performed.

Quantification of Pathologic Air Trapping in Lung Transplant Patients Using CT Density Mapping: Comparison with Other CT Air Trapping Measures.

To determine whether density mapping (DM) is more accurate for detection and quantification of pathologic air trapping (pAT) in patients after lung transplantation compared to other CT air trapping measures. One-hundred forty-seven lung and heart-lung transplant recipients underwent CT-examinations at functional residual capacity (FRC) and total lung capacity (TLC) and PFT six months after lung transplantation. Quantification of air trapping was performed with the threshold-based method in expiration (EXP), density mapping (DM) and the expiratory to inspiratory ratio of the mean lung density (E/I-ratio MLD).

Development and first clinical application of automated virtual reconstruction of unilateral midface defects.

Purpose: Computer-assisted surgery is used for decision making, treatment, and quality control throughout the reconstruction process of unilateral midface defects. The current approaches exploit the symmetry of the face by mirroring the intact side on the defect side using various segmentation methods. All commercially available implementations, however, are somewhat time consuming and dependent on the level of expertise of the user.

Bronchial wall measurements in patients after lung transplantation: evaluation of the diagnostic value for the diagnosis of bronchiolitis obliterans syndrome.

Objectives: To prospectively evaluate quantitative airway wall measurements of thin-section CT for the diagnosis of Bronchiolitis Obliterans Syndrome (BOS) following lung transplantation.

Materials And Methods: In 141 CT examinations, bronchial wall thickness (WT), the wall area percentage (WA%) calculated as the ratio of the bronchial wall area and the total area (sum of bronchial wall area and bronchial lumen area) and the difference of the WT on inspiration and expiration (WTdiff) were automatically measured in different bronchial generations. The measurements were correlated with the lung function parameters.

CT angiography for pulmonary embolism detection: the effect of breathing on pulmonary artery enhancement using a 64-row detector system.

Background: Computed tomography pulmonary angiography (CTPA) is used most often in routine clinical practice for the assessment of a suspected pulmonary embolism. The diagnostic accuracy relies on sufficient contrast enhancement.

Purpose: To evaluate whether image acquisition during shallow breathing can improve the image quality in patients with insufficient contrast enhancement during breath-hold examinations.

Development and evaluation of a software tool for the generation of virtual liver lesions in multidetector-row CT datasets.

Rationale And Objectives: Development and evaluation of a software tool for the insertion of simulated hypodense liver lesions in multidetector-row computed tomography (CT) datasets.

Materials And Methods: Forty software-generated hypodense liver lesions were inserted at random locations in 20 CT datasets by using the "alpha blending" technique and compared with 40 real metastatic lesions. The location, diameter (5-20 mm) and density of the simulated lesions were individually adjusted to closely resemble real lesions in each patient.

Influence of sinogram affirmed iterative reconstruction of CT data on image noise characteristics and low-contrast detectability: an objective approach.

Objectives: To utilize a novel objective approach combining a software phantom and an image quality metric to systematically evaluate the influence of sinogram affirmed iterative reconstruction (SAFIRE) of multidetector computed tomography (MDCT) data on image noise characteristics and low-contrast detectability (LCD).

Materials And Methods: A low-contrast and a high-contrast phantom were examined on a 128-slice scanner at different dose levels. The datasets were reconstructed using filtered back projection (FBP) and SAFIRE and virtual low-contrast lesions (-20HU) were inserted.

Evaluation of living liver donors using contrast enhanced multidetector CT - The radiologists impact on donor selection.

Background: Living donor liver transplantation (LDLT) is a valuable and legitimate treatment for patients with end-stage liver disease. Computed tomography (CT) has proven to be an important tool in the process of donor evaluation. The purpose of this study was to evaluate the significance of CT in the donor selection process.

A systematic approach towards the objective evaluation of low-contrast performance in MDCT: combination of a full-reference image fidelity metric and a software phantom.

Objectives: To assess the feasibility of an objective approach for the evaluation of low-contrast detectability in multidetector computed-tomography (MDCT) by combining a virtual phantom containing simulated lesions with an image quality metric.

Materials And Methods: A low-contrast phantom containing hypodense spheric lesions (-20 HU) was scanned on a 64-slice MDCT scanner at 4 different dose levels (25, 50, 100, 200 mAs). In addition, virtual round hypodense low-contrast lesions (20 HU object contrast) based on real CT data were inserted into the lesion-free section of the datasets.

Spirometric obstructive lung function pattern early after lung transplantation.

Background: An obstructive pattern in pulmonary function test is common after lung transplantation (LTx) and may be caused by multiple disorders. In this study, the impact and outcome of an obstructive spirometric pattern identified in transplant recipients early posttransplantation were investigated.

Methods: Analyzing all patients undergoing double LTx between September 1, 2007, and October 1, 2009, we separated patients with an obstructive (forced expiratory volume in 1 sec [FEV(1)]: vital capacity [VC] <0.

Influence of multiplanar reformations on low-contrast performance in thin-collimated multidetector computed tomography.

Objectives: : To analyze the influence of multiplanar reformations of thin-collimated multidetector computed tomography datasets on low-contrast performance.

Materials And Methods: : A low-contrast phantom simulating focal hypodense lesions (-20 HU object contrast) was scanned on a 64-slice spiral CT scanner at 4 different dose levels (25 mAs, 50 mAs, 100 mAs, 200 mAs, and no dose modulation). Other scanner parameters were as follows: tube voltage = 120 kVp, rotation time = 0.