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1.
Acta Radiol ; 64(3): 1038-1046, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35876445

RESUMO

BACKGROUND: Recent studies support magnetic resonance angiography (MRA) as a diagnostic tool for pulmonary arterial disease. PURPOSE: To determine MRA image quality and reproducibility, and the dependence of MRA image quality and reproducibility on disease severity in patients with chronic obstructive pulmonary disease (COPD) and cystic fibrosis (CF). MATERIAL AND METHODS: Twenty patients with COPD (mean age 66.5 ± 8.9 years; FEV1% = 42.0 ± 13.3%) and 15 with CF (mean age 29.3 ± 9.3 years; FEV1% = 66.6 ± 15.8%) underwent morpho-functional chest magnetic resonance imaging (MRI) including time-resolved MRA twice one month apart (MRI1, MRI2), and COPD patients underwent non-contrast computed tomography (CT). Image quality was assessed visually using standardized subjective 5-point scales. Contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were measured by regions of interest. Disease severity was determined by spirometry, a well-evaluated chest MRI score, and by computational CT emphysema index (EI) for COPD. RESULTS: Subjective image quality was diagnostic for all MRA at MRI1 and MRI2 (mean score = 4.7 ± 0.6). CNR and SNR were 4 43.8 ± 8.7 and 50.5 ± 8.7, respectively. Neither image quality score nor CNR or SNR correlated with FEV1% or chest MRI score for COPD and CF (r = 0.239-0.248). CNR and SNR did not change from MRI1 to MRI2 (P = 0.434-0.995). Further, insignificant differences in CNR and SNR between MRA at MRI1 and MRI2 did not correlate with FEV1% nor chest MRI score in COPD and CF (r = -0.238-0.183), nor with EI in COPD (r = 0.100-0.111). CONCLUSION: MRA achieved diagnostic quality in COPD and CF patients and was highly reproducible irrespective of disease severity. This supports MRA as a robust alternative to CT in patients with underlying muco-obstructive lung disease.


Assuntos
Angiografia por Ressonância Magnética , Doença Pulmonar Obstrutiva Crônica , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Angiografia por Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Pulmão/patologia , Imageamento por Ressonância Magnética/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/patologia
2.
Radiologe ; 59(Suppl 1): 10-20, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31172247

RESUMO

BACKGROUND: Despite recent advances in our knowledge about the pathophysiology and treatment of cystic fibrosis (CF), pulmonary involvement remains the most important determinant of morbidity and mortality in patients with CF. Since lung function testing may not be sensitive enough for subclinical disease progression, and because young children may have normal spirometry results over a longer period of time, imaging today plays an increasingly important role in clinical routine and research for the monitoring of CF lung disease. In this regard, chest magnetic resonance imaging (MRI) could serve as a radiation-free modality for structural and functional lung imaging. METHODS: Our research agenda encompassed the entire process of development, implementation, and validation of appropriate chest MRI protocols for use with infant and adult CF patients alike. RESULTS: After establishing a general MRI protocol for state-of-the-art clinical 1.5-T scanners based on the available sequence technology, a semiquantitative scoring system was developed followed by cross-validation of the method against the established modalities of computed tomography, radiography, and lung function testing. Cross-sectional studies were then set up to determine the sensitivity of the method for the interindividual variation of the disease and for changes in disease severity after treatment. Finally, the MRI protocol was implemented at multiple sites to be validated in a multicenter setting. CONCLUSION: After more than a decade, lung MRI has become a valuable tool for monitoring CF in clinical routine application and as an endpoint for clinical studies.


Assuntos
Fibrose Cística , Imageamento por Ressonância Magnética/métodos , Adulto , Criança , Pré-Escolar , Estudos Transversais , Fibrose Cística/diagnóstico por imagem , Feminino , Humanos , Lactente , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Tomografia Computadorizada por Raios X
3.
Am J Respir Crit Care Med ; 195(3): 349-359, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27575911

RESUMO

RATIONALE: Early onset and progression of lung disease in children with cystic fibrosis (CF) indicates that sensitive noninvasive outcome measures are needed for diagnostic monitoring and early intervention clinical trials. The lung clearance index (LCI) and chest magnetic resonance imaging (MRI) were shown to detect early lung disease in CF; however, the relationship between the two measures remains unknown. OBJECTIVES: To correlate the LCI with abnormalities detected by MRI and compare the sensitivity of the two techniques to detect responses to therapy for pulmonary exacerbations in children with CF. METHODS: LCI determined by age-adapted multiple breath washout techniques and MRI studies were performed in 97 clinically stable children with CF across the pediatric age range (0.2-21.1 yr). Furthermore, LCI (n = 26) or MRI (n = 10) were performed at the time of pulmonary exacerbation and after antibiotic therapy. MRI was evaluated using a dedicated morphofunctional score. MEASUREMENTS AND MAIN RESULTS: The LCI correlated with the global MRI score as well as MRI-defined airway wall abnormalities, mucus plugging, and abnormal lung perfusion in infants and toddlers (P < 0.05 to P < 0.001) and in older children (P < 0.001) with CF. LCI and MRI were sensitive to detect response to antibiotic therapy for pulmonary exacerbations. CONCLUSIONS: Our results indicate that LCI and MRI may be useful complementary tools for noninvasive monitoring and as quantitative endpoints in early intervention trials in children with CF. In this context, MRI enables detection of disease heterogeneity, including regional mucus plugging associated with abnormal lung perfusion in early CF lung disease. Clinical trial registered with www.clinicaltrials.gov (NCT 02270476).


Assuntos
Fibrose Cística/complicações , Progressão da Doença , Pulmão/patologia , Pulmão/fisiopatologia , Troca Gasosa Pulmonar/fisiologia , Adolescente , Testes Respiratórios/métodos , Criança , Pré-Escolar , Estudos Transversais , Fibrose Cística/diagnóstico por imagem , Fibrose Cística/patologia , Fibrose Cística/fisiopatologia , Feminino , Volume Expiratório Forçado , Alemanha , Humanos , Lactente , Pulmão/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Testes de Função Respiratória/métodos , Espirometria , Adulto Jovem
5.
Am J Respir Crit Care Med ; 189(8): 956-65, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24564281

RESUMO

RATIONALE: Studies demonstrating early structural lung damage in infants and preschool children with cystic fibrosis (CF) suggest that noninvasive monitoring will be important to identify patients who may benefit from early therapeutic intervention. Previous studies demonstrated that magnetic resonance imaging (MRI) detects structural and functional abnormalities in lungs from older patients with CF without radiation exposure. OBJECTIVES: To evaluate the potential of MRI to detect abnormal lung structure and perfusion in infants and preschool children with CF, and to monitor the response to therapy for pulmonary exacerbation. METHODS: MRI studies were performed in 50 children with CF (age, 3.1 ± 2.1 yr; range, 0-6 yr) in stable clinical condition (n = 40) or pulmonary exacerbation before and after antibiotic treatment (n = 10), and in 26 non-CF control subjects (age, 2.9 ± 1.9 yr). T1- and T2-weighted sequences before and after intravenous contrast and first-pass perfusion imaging were acquired, and assessed on the basis of a dedicated morphofunctional score. MEASUREMENTS AND MAIN RESULTS: MRI demonstrated bronchial wall thickening/bronchiectasis, mucus plugging, and perfusion deficits from the first year of life in most stable patients with CF (global score, 10.0 ± 4.0), but not in non-CF control subjects (score, 0.0 ± 0.0; P < 0.001). In patients with exacerbations, the global MRI score was increased to 18.0 ± 2.0 (P < 0.001), and was significantly reduced to 12.0 ± 3.0 (P < 0.05) after antibiotic therapy. CONCLUSIONS: MRI detected abnormalities in lung structure and perfusion, and response to therapy for exacerbations in infants and preschool children with CF. These results support the development of MRI for noninvasive monitoring and as an end point in interventional trials for early CF lung disease. Clinical trial registered with www.clinicaltrials.gov (NCT00760071).


Assuntos
Fibrose Cística/diagnóstico , Pulmão/patologia , Pulmão/fisiopatologia , Imageamento por Ressonância Magnética , Estudos de Casos e Controles , Pré-Escolar , Fibrose Cística/tratamento farmacológico , Fibrose Cística/patologia , Fibrose Cística/fisiopatologia , Diagnóstico Precoce , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença
7.
Am J Physiol Lung Cell Mol Physiol ; 307(1): L27-37, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24816486

RESUMO

The pathogenesis of ventilator-induced lung injury has predominantly been attributed to overdistension or mechanical opening and collapse of alveoli, whereas mechanical strain on the airways is rarely taken into consideration. Here, we hypothesized that mechanical ventilation may cause significant airway distension, which may contribute to the pathological features of ventilator-induced lung injury. C57BL/6J mice were anesthetized and mechanically ventilated at tidal volumes of 6, 10, or 15 ml/kg body wt. Mice were imaged by flat-panel volume computer tomography, and central airways were segmented and rendered in 3D for quantitative assessment of airway distension. Alveolar distension was imaged by intravital microscopy. Functional dead space was analyzed in vivo, and proinflammatory cytokine release was analyzed in isolated, ventilated tracheae. CT scans revealed a reversible, up to 2.5-fold increase in upper airway volume during mechanical ventilation compared with spontaneous breathing. Airway distension was most pronounced in main bronchi, which showed the largest volumes at tidal volumes of 10 ml/kg body wt. Conversely, airway distension in segmental bronchi and functional dead space increased almost linearly, and alveolar distension increased even disproportionately with higher tidal volumes. In isolated tracheae, mechanical ventilation stimulated the release of the early-response cytokines TNF-α and IL-1ß. Mechanical ventilation causes a rapid, pronounced, and reversible distension of upper airways in mice that is associated with an increase in functional dead space. Upper airway distension is most pronounced at moderate tidal volumes, whereas higher tidal volumes redistribute preferentially to the alveolar compartment. Airway distension triggers proinflammatory responses and may thus contribute relevantly to ventilator-induced pathologies.


Assuntos
Alvéolos Pulmonares/patologia , Respiração Artificial/efeitos adversos , Estresse Mecânico , Volume de Ventilação Pulmonar/fisiologia , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia , Animais , Capnografia , Inflamação , Interleucina-1beta/biossíntese , Interleucina-1beta/metabolismo , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Alvéolos Pulmonares/fisiopatologia , Tomografia Computadorizada por Raios X , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/metabolismo
8.
Respiration ; 87(4): 294-300, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24557362

RESUMO

BACKGROUND: Advanced-stage chronic obstructive pulmonary disease (COPD) is associated with severely altered respiratory dynamics. Dynamic airway instability is usually diagnosed by invasive bronchoscopy. Cine-computed tomography (CT) may be used alternatively, but is limited to predefined anatomical positions. Also, a paradoxical diaphragmatic motion has been described in patients with emphysema. OBJECTIVES: As the airways and chest wall show inherently high contrast to airway lumen and lung tissue, low-dose CT acquisitions potentially suffice for depicting tracheobronchial and chest wall motion. Therefore, we propose low-dose dynamic respiratory-gated multidetector CT (4D-CT) of the whole chest as a new method to assess respiratory dynamics. METHODS: 4D-CT was performed in 3 patients (52, 62 and 76 years old) with suspected tracheal instability due to COPD or tracheal stenosis at minimal pitch (0.09) and radiation exposure (1.4-1.9 mSv) during regular tidal breathing registered by a belt system. Image reconstruction involved a raw data-based iterative algorithm (1.5-mm slice thickness, 1.0-mm z-axis increment, 5% respiratory increment), resulting in a stack of 6,700 images, which were evaluated with a 4D-viewing tool. RESULTS: An excessive dynamic collapse of the trachea in combination with tracheobronchomalacia (TBM) of the main-stem and segmental bronchi, and a paradoxical diaphragmatic motion were demonstrated in 1 case. Moreover, we detected a saber-sheath trachea and main-stem TBM in another case. The third case showed a fixed tracheal stenosis. CONCLUSIONS: 4D-CT provides unprecedented z-axis coverage and time-resolved volumetric datasets of the whole chest. Airway instability, stenosis and paradoxical diaphragmatic motion may be assessed simultaneously, preceding interventions such as airway stabilization or lung volume reduction.


Assuntos
Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Mecânica Respiratória , Traqueia/diagnóstico por imagem , Idoso , Diafragma/diagnóstico por imagem , Diafragma/fisiopatologia , Estudos de Viabilidade , Tomografia Computadorizada Quadridimensional , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Parede Torácica/diagnóstico por imagem , Parede Torácica/fisiopatologia , Traqueia/fisiopatologia
9.
Respiration ; 88(3): 199-207, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25115833

RESUMO

BACKGROUND: Pirfenidone is a novel antifibrotic drug for the treatment of mild-to-moderate idiopathic pulmonary fibrosis (IPF). However, adverse events may offset treatment benefits and compliance. OBJECTIVES: To assess recent course of disease, adverse events and compliance in patients who started pirfenidone. METHODS: In an observational cohort study, 63 patients with mild-to-moderate IPF who started pirfenidone between May 2011 and June 2013 were reviewed. Pulmonary function, adverse events and treatment compliance were recorded at each clinic visit. Disease progression was defined as a reduction of vital capacity ≥10% and/or diffusion capacity (DLCO) ≥15%. RESULTS: Follow-up time on pirfenidone treatment was 11 (±7) months. Sixty-six percent of the patients continued with pirfenidone monotherapy and 34% of the patients received pirfenidone combined with corticosteroids (CCS) and/or N-acetylcysteine (NAC). There was a nonsignificant reduction in mean decline of percent predicted forced vital capacity after treatment start (0.7 ± 10.9%) compared to the pretreatment period (6.6 ± 6.7%, p = 0.098). Sixty-two percent of the patients had stable disease on pirfenidone treatment. Adverse events affected 85% of the patients, leading to discontinuation of pirfenidone in 20%. Adverse events and treatment discontinuation were seen more frequently in patients with concomitant CCS and/or NAC treatment. CONCLUSIONS: Adverse events affect the majority of patients treated with pirfenidone, but are mostly manageable with supportive measures. In this heterogeneous patient group, a nonsignificant effect of pirfenidone treatment on pulmonary function was seen, underlining the need for more data on patient selection criteria and efficacy of pirfenidone, particularly in patients with coexistent emphysema and concomitant NAC/CCS treatment.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Fibrose Pulmonar Idiopática/tratamento farmacológico , Piridonas/uso terapêutico , Acetilcisteína/uso terapêutico , Corticosteroides/uso terapêutico , Idoso , Estudos de Coortes , Progressão da Doença , Toxidermias/etiologia , Quimioterapia Combinada , Expectorantes/uso terapêutico , Fadiga/induzido quimicamente , Feminino , Gastroenteropatias/induzido quimicamente , Alemanha , Humanos , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Estudos Retrospectivos , Centros de Atenção Terciária , Resultado do Tratamento , Capacidade Vital , Redução de Peso
10.
Eur Respir J ; 41(4): 943-51, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22835610

RESUMO

Recently, a novel classification system based on tumour architecture and with high prognostic impact has been proposed for pulmonary adenocarcinomas (ADCs). For imaging-based prediction of histological ADC subtypes and, thus, prognosis, it is of paramount importance to investigate the correlations of radio- and histomorphological parameters. Associations between histomorphological ADC growth patterns (lepidic, acinar, papillary, micropapillary and solid) and data from pre-operative assessment by computed tomography (CT) imaging of 174 resected pulmonary ADCs were analysed. Margin configuration as well as solidity/ground glass opacity of an ADC was associated with distinct histomorphological ADC growth patterns. Solid-predominant ADCs usually had smooth margins and were also solid in CT scans, while lepidic-predominant ADCs had no predominant margin pattern, were located in the periphery, showed a positive bronchogram and were frequently associated with solidity/ground glass opacity. In addition, nonspherical tumour growth was a negative predictor of overall and disease-specific patient survival. We defined CT morphological parameters that were associated with histomorphological growth patterns of pulmonary ADCs. These data may form the basis for the development of future prognostic algorithms in the palliative setting, which include an integrated evaluation of biopsy histomorphology and CT scan morphology of nonresectable pulmonary ADC.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Pulmão/patologia , Tomografia Computadorizada por Raios X , Algoritmos , Biópsia , Intervalo Livre de Doença , Detecção Precoce de Câncer , Humanos , Metástase Neoplásica , Prognóstico , Resultado do Tratamento
11.
Magn Reson Med ; 69(1): 229-37, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22392633

RESUMO

The purpose of this work was to validate ventilation-weighted (VW) and perfusion-weighted (QW) Fourier decomposition (FD) magnetic resonance imaging (MRI) with hyperpolarized (3)He MRI and dynamic contrast-enhanced perfusion (DCE) MRI in a controlled animal experiment. Three healthy pigs were studied on 1.5-T MR scanner. For FD MRI, the VW and QW images were obtained by postprocessing of time-resolved lung image sets. DCE acquisitions were performed immediately after contrast agent injection. (3)He MRI data were acquired following the administration of hyperpolarized helium and nitrogen mixture. After baseline MR scans, pulmonary embolism was artificially produced. FD MRI and DCE MRI perfusion measurements were repeated. Subsequently, atelectasis and air trapping were induced, which followed with FD MRI and (3)He MRI ventilation measurements. Distributions of signal intensities in healthy and pathologic lung tissue were compared by statistical analysis. Images acquired using FD, (3)He, and DCE MRI in all animals before the interventional procedure showed homogeneous ventilation and perfusion. Functional defects were detected by all MRI techniques at identical anatomical locations. Signal intensity in VW and QW images was significantly lower in pathological than in healthy lung parenchyma. The study has shown usefulness of FD MRI as an alternative, noninvasive, and easily implementable technique for the assessment of acute changes in lung function.


Assuntos
Meios de Contraste , Gadolínio DTPA , Hélio , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Relação Ventilação-Perfusão , Animais , Análise de Fourier , Isótopos , Pulmão/anatomia & histologia , Masculino , Embolia Pulmonar/patologia , Embolia Pulmonar/fisiopatologia , Ventilação Pulmonar , Sus scrofa
12.
ERJ Open Res ; 9(2)2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37009019

RESUMO

Background: Bronchial artery dilatation (BAD) is associated with haemoptysis in advanced cystic fibrosis (CF) lung disease. Our aim was to evaluate BAD onset and its association with disease severity by magnetic resonance imaging (MRI). Methods: 188 CF patients (mean±sd age 13.8±10.6 years, range 1.1-55.2 years) underwent annual chest MRI (median three exams, range one to six exams), contributing a total of 485 MRI exams including perfusion MRI. Presence of BAD was evaluated by two radiologists in consensus. Disease severity was assessed using the validated MRI scoring system and spirometry (forced expiratory volume in 1 s (FEV1) % pred). Results: MRI demonstrated BAD in 71 (37.8%) CF patients consistently from the first available exam and a further 10 (5.3%) patients first developed BAD during surveillance. Mean MRI global score in patients with BAD was 24.5±8.3 compared with 11.8±7.0 in patients without BAD (p<0.001) and FEV1 % pred was lower in patients with BAD compared with patients without BAD (60.8% versus 82.0%; p<0.001). BAD was more prevalent in patients with chronic Pseudomonas aeruginosa infection versus in patients without infection (63.6% versus 28.0%; p<0.001). In the 10 patients who newly developed BAD, the MRI global score increased from 15.1±7.8 before to 22.0±5.4 at first detection of BAD (p<0.05). Youden indices for the presence of BAD were 0.57 for age (cut-off 11.2 years), 0.65 for FEV1 % pred (cut-off 74.2%) and 0.62 for MRI global score (cut-off 15.5) (p<0.001). Conclusions: MRI detects BAD in patients with CF without radiation exposure. Onset of BAD is associated with increased MRI scores, worse lung function and chronic P. aeruginosa infection, and may serve as a marker of disease severity.

13.
Front Med (Lausanne) ; 9: 1022981, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353218

RESUMO

Background: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) allows the assessment of pulmonary perfusion, which may play a key role in the development of muco-obstructive lung disease. One problem with quantifying pulmonary perfusion is the high variability of metrics. Quantifying the extent of abnormalities using unsupervised clustering algorithms in residue function maps leads to intrinsic normalization and could reduce variability. Purpose: We investigated the reproducibility of perfusion defects in percent (QDP) in clinically stable patients with cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD). Methods: 15 CF (29.3 ± 9.3y, FEV1%predicted = 66.6 ± 15.8%) and 20 COPD (66.5 ± 8.9y, FEV1%predicted = 42.0 ± 13.3%) patients underwent DCE-MRI twice 1 month apart. QDP, pulmonary blood flow (PBF), and pulmonary blood volume (PBV) were computed from residue function maps using an in-house quantification pipeline. A previously validated MRI perfusion score was visually assessed by an expert reader. Results: Overall, mean QDP, PBF, and PBV did not change within 1 month, except for QDP in COPD (p < 0.05). We observed smaller limits of agreement (± 1.96 SD) related to the median for QDP (CF: ± 38%, COPD: ± 37%) compared to PBF (CF: ± 89%, COPD: ± 55%) and PBV (CF: ± 55%, COPD: ± 51%). QDP correlated moderately with the MRI perfusion score in CF (r = 0.46, p < 0.05) and COPD (r = 0.66, p < 0.001). PBF and PBV correlated poorly with the MRI perfusion score in CF (r =-0.29, p = 0.132 and r =-0.35, p = 0.067, respectively) and moderately in COPD (r =-0.57 and r =-0.57, p < 0.001, respectively). Conclusion: In patients with muco-obstructive lung diseases, QDP was more robust and showed a higher correlation with the MRI perfusion score compared to the traditionally used perfusion metrics PBF and PBV.

14.
Radiology ; 260(2): 551-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21586678

RESUMO

PURPOSE: To compare unenhanced lung ventilation-weighted (VW) and perfusion-weighted (QW) imaging based on Fourier decomposition (FD) magnetic resonance (MR) imaging with the clinical reference standard single photon emission computed tomography (SPECT)/computed tomography (CT) in an animal experiment. MATERIALS AND METHODS: The study was approved by the local animal care committee. Lung ventilation and perfusion was assessed in seven anesthetized pigs by using a 1.5-T MR imager and SPECT/CT. For time-resolved FD MR imaging, sets of lung images were acquired by using an untriggered two-dimensional balanced steady-state free precession sequence (repetition time, 1.9 msec; echo time, 0.8 msec; acquisition time per image, 118 msec; acquisition rate, 3.33 images per second; flip angle, 75°; section thickness, 12 mm; matrix, 128 × 128). Breathing displacement was corrected with nonrigid image registration. Parenchymal signal intensity was analyzed pixelwise with FD to separate periodic changes of proton density induced by respiration and periodic changes of blood flow. Spectral lines representing respiratory and cardiac frequencies were integrated to calculate VW and QW images. Ventilation and perfusion SPECT was performed after inhalation of dispersed technetium 99m ((99m)Tc) and injection of (99m)Tc-labeled macroaggregated albumin. FD MR imaging and SPECT data were independently analyzed by two physicians in consensus. A regional statistical analysis of homogeneity and pathologic signal changes was performed. RESULTS: Images acquired in healthy animals by using FD MR imaging and SPECT showed a homogeneous distribution of VW and QW imaging and pulmonary ventilation and perfusion, respectively. The gravitation-dependent signal distribution of ventilation and perfusion in all animals was similarly observed at FD MR imaging and SPECT. Incidental ventilation and perfusion defects were identically visualized by using both modalities. CONCLUSION: This animal experiment demonstrated qualitative agreement in the assessment of regional lung ventilation and perfusion between contrast media-free and radiation-free FD MR imaging and conventional SPECT/CT.


Assuntos
Pulmão/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Animais , Feminino , Processamento de Imagem Assistida por Computador , Pulmão/diagnóstico por imagem , Pertecnetato Tc 99m de Sódio , Estatísticas não Paramétricas , Suínos , Agregado de Albumina Marcado com Tecnécio Tc 99m
15.
J Magn Reson Imaging ; 32(6): 1370-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21105141

RESUMO

Computed tomography (CT) is the current "gold standard" for assessment of lung morphology and is so far the most reliable imaging modality for monitoring cystic fibrosis (CF) lung disease. CT has a much higher radiation exposure than chest x-ray. The cumulative radiation dose for life-long repeated CT scans has limited its use for CF patients as their life expectancy increases. Clearly, no dose would be preferable over low dose when the same or more relevant information can be obtained. Magnetic resonance imaging (MRI) is comparable to CT with regard to the detection of most morphological changes in the CF lung. It is thought to be less sensitive to detect small airway disease. At the same time, MRI is superior to CT when it comes to the assessment of functional changes such as altered pulmonary perfusion. The recommendation is to further reduce radiation dose related to the use of CT and to use MRI in the follow-up of morphological changes where possible.


Assuntos
Fibrose Cística/diagnóstico por imagem , Fibrose Cística/patologia , Pneumopatias/diagnóstico por imagem , Pneumopatias/patologia , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Diagnóstico por Imagem/métodos , Humanos , Pulmão/patologia , Perfusão , Radiografia Torácica/métodos
16.
Pediatr Radiol ; 40(6): 844-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20432002

RESUMO

Cystic fibrosis (CF) lung disease is caused by mutations in the CFTR-gene and remains one of the most frequent lethal inherited diseases in the Caucasian population. Given the progress in CF therapy and the consecutive improvement in prognosis, monitoring of disease progression and effectiveness of therapeutic interventions with repeated imaging of the CF lung plays an increasingly important role. So far, the chest radiograph has been the most widely used imaging modality to monitor morphological changes in the CF lung. CT is the gold standard for assessment of morphological changes of airways and lung parenchyma. Considering the necessity of life-long repeated imaging studies, the cumulative radiation doses reached with CT is problematic for CF patients. A sensitive, non-invasive and quantitative technique without radiation exposure is warranted for monitoring of disease activity. In previous studies, MRI proved to be comparable to CT regarding the detection of morphological changes in the CF lung without using ionising radiation. Furthermore, MRI was shown to be superior to CT regarding assessment of functional changes of the lung. This review presents the typical morphological and functional MR imaging findings with respect to MR-based follow-up of CF lung disease. MRI offers a variety of techniques for morphological and functional imaging of the CF lung. Using this radiation free technique short- and long-term follow-up studies are possible enabling an individualised guidance of the therapy.


Assuntos
Fibrose Cística/diagnóstico , Pulmão/diagnóstico por imagem , Pulmão/patologia , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Doença Crônica , Feminino , Seguimentos , Humanos , Masculino
17.
PLoS One ; 15(8): e0237434, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797096

RESUMO

OBJECTIVES: To systematically evaluate the influence of acquisition settings in conjunction with raw-data based iterative image reconstruction (IR) on lung densitometry based on multi-row detector computed tomography (CT) in an anthropomorphic chest phantom. MATERIALS AND METHODS: Ten porcine heart-lung explants were mounted in an ex vivo chest phantom shell, six with highly and four with low attenuating chest wall. CT (Somatom Definition Flash, Siemens Healthineers) was performed at 120kVp and 80kVp, each combined with current-time products of 120, 60, 30, and 12mAs, and was reconstructed with filtered back projection (FBP) and IR (Safire, Siemens Healthineers). Mean lung density (LD), air density (AD) and noise were measured by semi-automated region-of interest (ROI) analysis, with 120kVp/120 mAs serving as the standard of reference. RESULTS: Using IR, noise in lung parenchyma was reduced by ~ 31% at high attenuating chest wall and by ~ 22% at low attenuating chest wall compared to FBP, respectively (p<0.05). IR induced changes in the order of ±1 HU to mean absolute LD and AD compared to corresponding FBP reconstructions which were statistically significant (p<0.05). CONCLUSIONS: Densitometry is influenced by acquisition parameters and reconstruction algorithms to a degree that may be clinically negligible. However, in longitudinal studies and clinical research identical protocols and potentially other measures for calibration may be required.


Assuntos
Pulmão/fisiologia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X , Algoritmos , Animais , Antropometria , Densitometria , Pulmão/diagnóstico por imagem , Pulmão/efeitos da radiação , Exposição à Radiação , Razão Sinal-Ruído , Suínos , Tórax/diagnóstico por imagem
18.
Ann Am Thorac Soc ; 17(6): 714-723, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32142375

RESUMO

Rationale: Chronic rhinosinusitis (CRS) contributes to disease burden of patients with cystic fibrosis (CF). However, its onset and progression in infants and preschool children with CF remain poorly understood.Objectives: To determine the prevalence and extent of CRS in young children with CF using magnetic resonance imaging (MRI).Methods: MRI was performed in sedation in 67 infants and preschool children with CF (mean age 2.3 ± 2.1 yr; range 0-6 yr) and 30 non-CF control subjects (3.5 ± 2.0 yr; range 0-6 yr). Paranasal sinus dimensions and structural abnormalities, including mucosal swelling; mucopyoceles; and nasal polyps of the maxillary, frontal, sphenoid, and ethmoid sinuses; and, in addition, medial maxillary sinus wall deformation, were assessed using a dedicated CRS MRI scoring system.Results: Pneumatization and dimensions of paranasal sinuses did not differ between the two groups. MRI detected an increased prevalence of mucosal swelling (83% vs. 17%; P < 0.001), mucopyoceles (75% vs. 2%; P < 0.001), polyps (26% vs. 7%; P < 0.001), and maxillary sinus wall deformation (68% vs. 2%; P < 0.001) in infants and preschool children with CF compared with age-matched control subjects. Furthermore, the extent of these abnormalities was also increased with a MRI sum score of 22.9 ± 10.9 in CF compared with 4.5 ± 7.6 in non-CF control subjects (P < 0.001).Conclusions: MRI detected normal dimensions of paranasal sinuses, and a high prevalence and severity of paranasal sinus abnormalities due to CRS in infants and preschool children with CF without radiation exposure. Our results support the development of MRI for sensitive noninvasive diagnosis and monitoring of CRS in young children with CF, and as outcome measures for clinical trials.Clinical trial registered with www.clinicaltrials.gov (NCT00760071).


Assuntos
Fibrose Cística/complicações , Imageamento por Ressonância Magnética , Seios Paranasais/anormalidades , Rinite/patologia , Sinusite/patologia , Pré-Escolar , Doença Crônica , Estudos Transversais , Fibrose Cística/diagnóstico por imagem , Fibrose Cística/patologia , Progressão da Doença , Feminino , Humanos , Lactente , Masculino , Pólipos Nasais/patologia , Seios Paranasais/patologia , Estudos Prospectivos
19.
Magn Reson Med ; 62(3): 656-64, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19585597

RESUMO

Assessment of regional lung perfusion and ventilation has significant clinical value for the diagnosis and follow-up of pulmonary diseases. In this work a new method of non-contrast-enhanced functional lung MRI (not dependent on intravenous or inhalative contrast agents) is proposed. A two-dimensional (2D) true fast imaging with steady precession (TrueFISP) pulse sequence (TR/TE = 1.9 ms/0.8 ms, acquisition time [TA] = 112 ms/image) was implemented on a 1.5T whole-body MR scanner. The imaging protocol comprised sets of 198 lung images acquired with an imaging rate of 3.33 images/s in coronal and sagittal view. No electrocardiogram (ECG) or respiratory triggering was used. A nonrigid image registration algorithm was applied to compensate for respiratory motion. Rapid data acquisition allowed observing intensity changes in corresponding lung areas with respect to the cardiac and respiratory frequencies. After a Fourier analysis along the time domain, two spectral lines corresponding to both frequencies were used to calculate the perfusion- and ventilation-weighted images. The described method was applied in preliminary studies on volunteers and patients showing clinical relevance to obtain non-contrast-enhanced perfusion and ventilation data.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Pulmão/fisiologia , Angiografia por Ressonância Magnética/métodos , Circulação Pulmonar/fisiologia , Mecânica Respiratória/fisiologia , Meios de Contraste , Análise de Fourier , Humanos , Aumento da Imagem/métodos , Pulmão/anatomia & histologia , Movimento , Prótons , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Exp Ther Med ; 17(1): 967-973, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30651888

RESUMO

Although some of the associations between chronic obstructive pulmonary disease (COPD) and atherosclerosis are based on shared risk factors such as smoking, recent epidemiological evidence suggests that COPD is a risk factor for vascular disease due to systemic inflammation. The present study assessed the hypothesis that disease severity (as expressed by the GOLD stage) independently predicts the extent of vascular calcifications. A total of 160 smokers diagnosed with COPD (GOLD I-IV, 40 subjects of each GOLD stage) and 40 smokers at risk (GOLD 0; median age of 60 years old; Q1:56;Q3:65; 135 males and 65 females) underwent non-contrast, non-electrocardiography synchronized chest computerised tomography. The volume of thoracic aortic calcifications was quantified semi-automatically within a region from T1 through T12. Multiparametric associations with GOLD stage, smoking history, sex, age, body mass index and emphysema index were evaluated using generalized linear regression analysis. Thoracic aortic calcifications were highly prevalent in this cohort (187/200 subjects, 709 (Q1:109;Q3:2163) mm3). Analysis of variance on ranks demonstrated a significant difference in calcium between different GOLD-stages as well as patients at risk of COPD (F=36.8, P<0.001). In the multivariable analysis, GOLD-stages were indicated to be predictive of thoracic aortic calcifications (P≤0.0033) besides age (P<0.0001), while age appeared to be the strongest predictor. Other variables were not statistically linked to thoracic aortic calcifications in the multivariable model. COPD severity, as expressed by the GOLD-stage, is a significant predictor of thoracic aortic calcifications, independent of covariates such as age or tobacco consumption.

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