Sylvia Nyilas

MRI showed a regional decrease of lung perfusion after exposure to tobacco smoke and a local increase of lung perfusion after electronic nicotine delivery systems use. Background Evidence regarding short-term effects of electronic nicotine delivery systems (ENDS) and tobacco smoke on lung ventilation and perfusion is limited. Purpose To examine the immediate effe...

Short-term effect of e-cigarette and tobacco smoke on ventilation and perfusion in the lung: Assessment with functional MRI Sylvia Nyilas, MD, PhD^1*^, Grzegorz Bauman, PhD^2,3*^, Insa Korten^4^, MD, PhD, Orso Pusterla^2,3,5^, M.Sc, PhD, Florian Singer^4^, MD, PhD, Michael Ith^1^, PhD, Cindy Groen^6^, Anna Schöni^6^, PhD, Johannes T. Heverhagen MD, PhD^1^, Andreas Christe^1^, MD,

Zusammenfassung: Klinisches/methodisches Problem: Die differenzierte Beurteilung von Gasaustauschprozessen, Lungenzirkulation sowie die Erkennung struktureller Veränderungen sind wesentlich für die Therapie von Patienten mit Mukoviszidose (zystische Fibrose, CF). Klinische Lungenfunktionstests sind oft nicht hinreichend spezifisch sowie häufig nicht durchführbar.Radiologische Standardverfahren: Standardverfahren in der Lungendiagnostik sind die konventionell radiologische Thoraxbildgebung und die Computertomographie (CT) zur morphologischen Darstellung. In aktuellen Studien wird zur strukturellen Darstellung der Lunge zusätzlich die Magnetresonanztomographie (MRT) verwendet. Die funktionelle Bildgebung ist vorerst nur auf spezialisierte Zentren beschränkt.Methodische Innovationen: Zur Darstellung der Lungenventilation stehen die MRT mit hyperpolarisierten Gasen und die Fourier-Dekompositions/Matrix-Pencil-MRT (FD/MP-MRT) zur Verfügung. Zur Perfusionsbestimmung können u. a. die dynamische kontrastmittelverstärkte MRT (DCE-MRT) oder kontrastmittelfreie Methoden wie die FD-MRT angewendet werden.Leistungsfähigkeit: Die funktionelle MRT erlaubt einen genaueren Einblick in die Pathophysiologie der Lungenfunktion auf regionaler Ebene. Vorteile gegenüber den röntgenbasierten Verfahren sind die fehlende Strahlenbelastung, die Vielzahl der über verschiedene Kontraste zugänglichen Parameter der Lungenfunktion sowie die gute Wiederholbarkeit.Bewertung: Funktionelle Messungen sind insbesondere zur frühzeitigen Erkennung von Lungenfunktionseinschränkungen unabdingbar. Ausreichende Erfahrungen in der klinischen Anwendung bei CF existieren nur für bestimmte MRT-Verfahren.Empfehlung für die Praxis: Ein klinischer Einsatz der genannten Verfahren sollte mit Ausnahme der DCE-MRT nur innerhalb von Studien erfolgen.

Posttraumatic pulmonary artery pseudoaneurysm is a very rare, yet potentially lethal complication after thoracic trauma. Pulmonary artery pseudoaneurysm is associated with high mortality. Still literature highlights that untreated, lesions can enlarge, rupture, and lead to exsanguination and death. We present a case of a posttraumatic peripheral pulmonary artery pseudoaneurysm with complete disappearance after one year. This case confirms that conservative treatment can be an effective option in asymptomatic and stable patients.

Parametric spatial transformation models have been successfully applied to image registration tasks. In such models, the transformation of interest is parameterized by a fixed set of basis functions as for example B-splines. Each basis function is located on a fixed regular grid position among the image domain, because the transformation of interest is not known in advance. As a consequence, not all basis functions will necessarily contribute to the final transformation which results in a non-compact representation of the transformation. We reformulate the pairwise registration problem as a recursive sequence of successive alignments. For each element in the sequence, a local deformation defined by its position, shape, and weight is computed by our recurrent registration neural network. The sum of all local deformations yield the final spatial alignment of both images. Formulating the registration problem in this way allows the network to detect non-aligned regions in the images and to learn how to locally refine the registration properly. In contrast to current non-sequence-based registration methods, our approach iteratively applies local spatial deformations to the images until the desired registration accuracy is achieved. We trained our network on 2D magnetic resonance images of the lung and compared our method to a standard parametric B-spline registration. The experiments show, that our method performs on par for the accuracy but yields a more compact representation of the transformation. Furthermore, we achieve a speedup of around 15 compared to the B-spline registration.

Primary ciliary dyskinesia (PCD) is a genetic, heterogeneous disease caused by dysfunction of cilia. Evidence is sparse and reports of lung function of PCD patients ranges from normal to severe impairment. This systematic review and meta-analysis of studies of lung function of PCD patients examines the spirometric indices of PCD patients and differences by age group and sex. We searched PubMed, Embase, and Scopus for studies that described lung function in ≥10 patients with PCD. We performed meta-analyses and metaregression to explain heterogeneity. We included 24 studies, ranging from 13-158 patients per study. The most commonly reported spirometric indices were forced expiratory volume in 1 sec (FEV1) and forced vital capacity (FVC) presented as mean and standard deviation of percent of predicted values. We found considerable heterogeneity for both parameters (I ² range 94-96%). The heterogeneity remained when we stratified the analysis by age; however, FEV1 in adult patients was lower. Even after taking into account explanatory factors, the largest part of the between-studies variance remained unexplained. Heterogeneity could be explained by genetic differences between study populations, methodological factors related to the variability of study inclusion criteria, or details on the performance and evaluation of lung function measurements that we could not account for. Prospective studies therefore need to use standardised protocols and international reference values. These results underline the possibility of distinct PCD phenotypes as in other chronic respiratory diseases. Detailed characterisation of these phenotypes and related genotypes is needed in order to better understand the natural history of PCD.

Background and objective: Idiopathic pulmonary fibrosis (IPF) is a devastating progressive lung disease affecting the parenchyma. Nitrogen multiple‐breath washout (N₂‐MBW) is a lung function test that measures ventilation inhomogeneity, a biomarker of small airway disease. We assessed clinical properties of N₂‐MBW in IPF.Methods: In this prospective cohort pilot study, 25 IPF patients and 25 healthy controls were assessed at baseline and 10 patients at median 6.2 months later. Outcomes included the lung clearance index (LCI) from N₂‐MBW, forced vital capacity (FVC) from spirometry, diffusion capacity of the lungs for carbon monoxide (DL_CO), bronchiectasis score from computed tomography scans, the Gender–Age–Physiology (GAP score for IPF) stage and death or lung transplantation (LTx). Study end points were feasibility, repeatability, discriminative capacity and correlation with disease severity and structural lung damage.Results: All patients were able to perform N₂‐MBW. LCI was repeatable and reproducible. Median (interquartile range (IQR)) LCI in IPF was 11.6 (10.1–13.8) in IPF versus 7.3 (6.9–8.4) in controls (P < 0.0001). LCI correlated with DL_CO corrected for haemoglobin (corrDL_CO; r = −0.49, P = 0.016), bronchiectasis score (r = 0.45, P = 0.024) and the GAP stage (r = 0.59, P = 0.002), but not with FVC. FVC was not related to bronchiectasis. During follow‐up, six patients died and one received LTx. LCI correlated with the latter compound outcome: hazard ratio (95% CI) was 2.43 (1.26; 4.69) per one LCI SD from the patient population.Conclusion: N₂‐MBW is a feasible, reliable and valid lung function test in IPF. LCI correlates with diffusion impairment, structural airway damage and clinical disease severity. LCI is a promising surveillance tool in IPF that may predict mortality.