Journal of Thoracic Imaging最新文献

Purpose: To quantitatively analyze lung elasticity in idiopathic pulmonary fibrosis (IPF) using elastic registration based on 3-dimensional pulmonary magnetic resonance imaging (3D-PMRI) and to assess its' correlations with the severity of IPF patients.

Material and methods: Thirty male patients with IPF (mean age: 62±6 y) and 30 age-matched male healthy controls (mean age: 62±6 y) were prospectively enrolled. 3D-PMRI was acquired with a 3-dimensional ultrashort echo time sequence in end-inspiration and end-expiration. MR images were registered from end-inspiration to end-expiration with the elastic registration algorithm. Jacobian determinants were calculated from deformation fields on color maps. The log means of the Jacobian determinants (Jac-mean) and Dice similarity coefficient were used to describe lung elasticity between 2 groups. Then, the correlation of lung elasticity with dyspnea Medical Research Council (MRC) score, exercise tolerance, health-related quality of life, lung function, and the extent of pulmonary fibrosis on chest computed tomography were analyzed.

Results: The Jac-mean of IPF patients (-0.19, [IQR: -0.22, -0.15]) decreased (absolute value), compared with healthy controls (-0.28, [IQR: -0.31, -0.24], P<0.001). The lung elasticity in IPF patients with dyspnea MRC≥3 (Jac-mean: -0.15; Dice: 0.06) was significantly lower than MRC 1 (Jac-mean: -0.22, P=0.001; Dice: 0.10, P=0.001) and MRC 2 (Jac-mean: -0.21, P=0.007; Dice: 0.09, P<0.001). In addition, the Jac-mean negatively correlated with forced vital capacity % (r=-0.487, P<0.001), forced expiratory volume 1% (r=-0.413, P=0.004), TLC% (r=-0.488, P<0.001), diffusing capacity of the lungs for carbon monoxide % predicted (r=-0.555, P<0.001), 6-minute walk distance (r=-0.441, P=0.030) and positively correlated with respiratory symptoms (r=0.430, P=0.042). Meanwhile, the Dice similarity coefficient positively correlated with forced vital capacity % (r=0.577, P=0.004), forced expiratory volume 1% (r=0.526, P=0.012), diffusing capacity of the lungs for carbon monoxide % predicted (r=0.435, P=0.048), 6-minute walk distance (r=0.473, P=0.016), final peripheral oxygen saturation (r=0.534, P=0.004), the extent of fibrosis on chest computed tomography (r=-0.421, P=0.021) and negatively correlated with activity (r=-0.431, P=0.048).

Conclusion: Lung elasticity decreased in IPF patients and correlated with dyspnea, exercise tolerance, health-related quality of life, lung function, and the extent of pulmonary fibrosis. The lung elasticity based on elastic registration of 3D-PMRI may be a new nonradiation imaging biomarker for quantitative evaluation of the severity of IPF.

Purpose: The purpose of this study was to identify differences in imaging features between patients with confirmed right middle lobe (RML) torsion compared to those suspected yet without torsion.

Materials and methods: This retrospective study entailing a search of radiology reports from April 1, 2014, to April 15, 2021, resulted in 52 patients with suspected yet without lobar torsion and 4 with confirmed torsion, supplemented by 2 additional cases before the search period for a total of 6 confirmed cases. Four thoracic radiologists (1 an adjudicator) evaluated chest radiographs and computed tomography (CT) examinations, and Fisher exact and Mann-Whitney tests were used to identify any significant differences in imaging features (P<0.05).

Results: A reversed halo sign was more frequent for all readers (P=0.001) in confirmed RML torsion than patients without torsion (83.3% vs. 0% for 3 readers, one the adjudicator). The CT coronal bronchial angle between RML bronchus and bronchus intermedius was larger (P=0.035) in torsion (121.28 degrees) than nontorsion cases (98.26 degrees). Patients with torsion had a higher percentage of ground-glass opacity in the affected lobe (P=0.031). A convex fissure towards the adjacent lobe on CT (P=0.009) and increased lobe volume on CT (P=0.001) occurred more often in confirmed torsion.

Conclusion: A reversed halo sign, larger CT coronal bronchial angle, greater proportion of ground-glass opacity, fissural convexity, and larger lobe volume on CT may aid in early recognition of the rare yet highly significant diagnosis of lobar torsion.

In this report and analysis of the results of a late 2021 post-COVID pandemic survey of members of the Society of Thoracic Radiology, we compared cardiothoracic radiologist workloads and burnout rates with those obtained from a prepandemic survey of society members. The more recent survey also asked respondents to provide a subjective assessment of their individual workload capacity should they be required to read cases at a section average daily case work volume, and this assessment was correlated with burnout rates. To measure nonrelative value unit workload, we requested data on non-case-related work responsibilities including teaching and multidisciplinary conferences that were not assessed in the first survey. In addition, we asked respondents to provide information on the availability of support services, personnel, and hardware and software tools that could improve work efficiency and reduce radiologist stress levels thereby mitigating burnout. We found that postpandemic case workload and cardiothoracic radiologists' burnout rates were similarly high compared with prepandemic levels with an overall burnout rate of 88% including a 100% burnout rate among women which had significantly increased. The range of radiologists' workload capacity is broad, although 80% of respondents reported that reading at an average sectional case volume was at or above their capacity, and the perceived capacity correlated with burnout measures. The presence of fellows and computer-aided diagnosis/artificial intelligence tools were each associated with significant decreases in burnout, providing 2 potential strategies that could be employed to address high cardiothoracic radiologist burnout rates.

Purpose: The inherent characteristics of lung tissue independent of breathing maneuvers may provide fundamental information for function assessment. This paper attempted to correlate textural signatures from computed tomography (CT) with pulmonary function measurements.

Materials and methods: Twenty-one lung cancer patients with thoracic 4-dimensional CT, DTPA-single-photon emission CT ventilation ( VNM ) scans, and available spirometry measurements (forced expiratory volume in 1 s, FEV 1 ; forced vital capacity, FVC; and FEV 1 /FVC) were collected. In subregional feature discovery, function-correlated candidates were identified from 79 radiomic features based on the statistical strength to differentiate defected/nondefected lung regions. Feature maps (FMs) of selected candidates were generated on 4-dimensional CT phases for a voxel-wise feature distribution study. Quantitative metrics were applied for validations, including the Spearman correlation coefficient (SCC) and the Dice similarity coefficient for FM- VNM spatial agreement assessments, intraclass correlation coefficient for FM interphase robustness evaluations, and FM-spirometry comparisons.

Results: At the subregion level, 8 function-correlated features were identified (effect size>0.330). The FMs of candidates yielded moderate-to-strong voxel-wise correlations with the reference VNM . The FMs of gray level dependence matrix dependence nonuniformity showed the highest robust (intraclass correlation coefficient=0.96 and P <0.0001) spatial correlation, with median SCCs ranging from 0.54 to 0.59 throughout the 10 breathing phases. Its phase-averaged FM achieved a median SCC of 0.60, a median Dice similarity coefficient of 0.60 (0.65) for high (low) functional lung volumes, and a correlation of 0.565 (0.646) between the spatially averaged feature values and FEV 1 (FEV 1 /FVC).

Conclusions: The results provide further insight into the underlying association of specific pulmonary textures with both local ( VNM ) and global (FEV 1 /FVC, FEV 1 ) functions. Further validations of the FM generalizability and the standardization of implementation protocols are warranted before clinically relevant investigations.

Purpose: Quantitative biomarkers from chest computed tomography (CT) can facilitate the incidental detection of important diseases. Atrial fibrillation (AFib) substantially increases the risk for comorbid conditions including stroke. This study investigated the relationship between AFib status and left atrial enlargement (LAE) on CT.

Materials and methods: A total of 500 consecutive patients who had undergone nongated chest CTs were included, and left atrium maximal axial cross-sectional area (LA-MACSA), left atrium anterior-posterior dimension (LA-AP), and vertebral body cross-sectional area (VB-Area) were measured. Height, weight, age, sex, and diagnosis of AFib were obtained from the medical record. Parametric statistical analyses and receiver operating characteristic curves were performed. Machine learning classifiers were run with clinical risk factors and LA measurements to predict patients with AFib.

Results: Eighty-five patients with a diagnosis of AFib were identified. Mean LA-MACSA and LA-AP were significantly larger in patients with AFib than in patients without AFib (28.63 vs. 20.53 cm 2 , P <0.000001; 4.34 vs. 3.5 cm, P <0.000001, respectively), both with area under the curves (AUCs) of 0.73. Multivariable logistic regression analysis including age, sex, and VB-Area with LA-MACSA improved the AUC for predicting AFib (AUC=0.77). An LA-MACSA threshold of 30 cm 2 demonstrated high specificity for AFib diagnosis at 92% and sensitivity of 48%, and LA-AP threshold at 4.5 cm demonstrated 90% specificity and 42% sensitivity. A Bayesian machine learning model using age, sex, height, body surface area, and LA-MACSA predicted AFib with an AUC of 0.743.

Conclusions: LA-MACSA or LA-AP can be rapidly measured from routine chest CT, and when >30 cm 2 and >4.5 cm, respectively, are specific indicators to predict patients at increased risk for AFib.

Purpose: The main objective of this study was to identify risk factors for post-percutaneous transthoracic lung biopsy (PTLB) pneumothorax and to establish and validate a predictive score for pneumothorax occurrence to identify patients eligible for outpatient care.

Material and methods: Patients who underwent PTLB between November 1, 2012 and March 1, 2017 were retrospectively evaluated for clinical and radiologic factors potentially related to pneumothorax occurrence. Multivariate logistic regression was used to identify risk factors, and the model coefficient for each factor was used to compute a score. Then, a validation cohort was prospectively evaluated from March 2018 to October 2019.

Results: Among the 498 eligible patients in the study cohort, pneumothorax occurred in 124 patients (24.9%) and required drainage in 34 patients (6.8%). Pneumothorax risk factors were chronic obstructive pulmonary disease (OR 95% CI 2.28[1.18-4.43]), several passages through the pleura (OR 95% CI 7.71[1.95-30.48]), an anterior biopsy approach (OR 95% CI 6.36 3.82-10.58]), skin-to-pleura distance ≤30 mm (OR 95% CI 2.25[1.09-6.65]), and aerial effusion >10 mm (OR 95% CI 9.27 [5.16-16.65]). Among the 236 patients in the prospective validation cohort, pneumothorax occurred in 18% and 8% were drained. A negative score (<73 points) predicted a probability of pneumothorax occurrence of 7.4% and late evacuation of 2.5% (OR 95% CI respectively 0.18[0.08-0.39] and 0.15[0.04-0.55]) and suggested a reduced length of hospital stay (P=0.009).

Conclusion: This predictive score for pneumothorax secondary to PTLB has high prognostic performance and accuracy to direct patients toward outpatient management.

Clinical trials: NCT03488043.

Purpose: The clinical significance of collateral flow for the ventricular function of patients with univentricular hearts is often debated. This study evaluates the impact of collateral flow on respiration-dependent preload modification and diastolic function in Fontan patients assessed by systemic and pulmonary vein (PV) flow patterns.

Materials and methods: Real-time phase-contrast cardiovascular magnetic resonance was performed in the right upper PV, ascending aorta, superior, and inferior vena cava (IVC) in 21 Fontan patients and 11 healthy individuals. The patients' respiratory cycle was divided into 4 periods to generate respiratory-dependent stroke volumes (SV i ). Conventional quantitative blood flow measurements were used to quantify and differentiate between low (group A) and high (group B) collateral flow.

Results: Group B showed significantly lower SV i IVC in inspiration, end-inspiration, expiration, and SV i ΔIVC compared with group A (23.6±4.8 mL/m 2 to 33.4±8.0; P =0.005). PV flow resulted in a lower mean SV i PV (11.6±7.6 mL/m 2 , vs. 14.0±11.4 mL/m 2 ) as well as a significantly lower peak systolic S-wave velocity (S max ) ( P =0.005), S/D-ratio (S max /peak diastolic wave velocity) ( P =0.015), and shorter diastolic deceleration time (DT D ; P =0.030; median DT D =134 ms) compared with group A (DT D =202 ms).

Conclusions: This study demonstrates the incapability of Fontan patients to properly increase preload by inspiration in the presence of significant collateral flow. The results further show that collateral flow is associated with a volume-deprived ventricle and impaired diastolic function.