Efectos del entrenamiento de la musculatura inspiratoria en personas con sobrepeso y obesidad / Effects of inspiratory muscle training in overweight and obese people

Objetivo: determinar los efectos que produce el entrenamiento de la musculatura inspiratoria (EMI) en la población con sobrepeso y obesidad respecto al rendimiento funcional, a la capacidad pulmonar y al perfil metabólico.Método: se llevó a cabo una revisión. Las búsquedas se realizaron en Pubmed, Scopus y Web of Science (WOS), usando descriptores: breathing excercise, inspiratory muscle training, inspiratory training, respiratory training y truncamiento de la palabra obes*. Se incluyeron ensayos clínicos publicados en inglés, español o francés desde 2010 hasta diciembre de 2021. Se seleccionaron los estudios que incluyeron población con obesidad/sobrepeso y si se aplicaba EMI.Resultados: se recogieron 15 estudios en la revisión. En total participaron 560 personas. Los estudios mostraron resultados beneficiosos del EMI: aumento de fuerza y resistencia de la musculatura inspiratoria, mejora el rendimiento funcional, disminuyendo el coste de oxígeno, el consumo de oxígeno e incrementando del consumo máximo de oxígeno. No provoca cambios en el perfil lipídico, aunque sí estimula la síntesis de hormona del crecimiento, reduciendo los problemas de hiposomatotropismo derivados de la obesidad. En cuanto a las cirugías bariátricas, el EMI se asoció con reducción de complicaciones derivadas del acto quirúrgico.Conclusión: el EMI es una práctica sencilla que reduce la sensación de disnea, aumenta la tolerancia al ejercicio y, por tanto, mejora la percepción de calidad de vida. Se trata de una terapia que se incluye en muchos programas de cuidados de Enfermería en el área hospitalaria y que puede ser aplicable en Atención Primaria y en el ámbito domiciliario.(AU)

Objective: to determine the effects caused by inspiratory muscle training (IMT) in the population with overweight and obesity regarding their functional performance, pulmonary volume, and metabolic profile.Method: a review was conducted. There were searches in Pubmed, Scopus and Web of Science (WOS), using the descriptors: breathing exercise, inspiratory muscle training, inspiratory training, respiratory training, and truncation of the term “obes”. Clinical trials published in English, Spanish or French were included, since 2010 to December 2021. Those studies including population with obesity / overweight and application of IMT were selected.Results: fifteen (15) studies were included in the review; in total, there were 560 participants. The studies showed beneficial results of IMT: increase in strength and resistance by the inspiratory muscles, improvement in functional performance reducing oxygen cost and oxygen use, and increase in the maximum use of oxygen. This did not entail changes in the lipid profile, although it stimulated growth hormone synthesis, thus reducing the hyposomatotropism problems derived of obesity. Regarding bariatric surgery, IMT was associated with a reduction in complications derived of the surgical act.Conclusion: IMT is a simple practice that reduces the sensation of dyspnea, increases tolerance to exercise and, therefore, improves the perception of quality of life. This therapy is included in many nursing care programs in the hospital setting, and it can be applicable in Primary Care and in the home setting.(AU)

A study of the correlation between total lung volume and the percent of low attenuation volume and PFT indicators in patients with preoperative lung cancer.

The objective was to explore the relationships between computed tomography (CT) lung volume parameters and pulmonary function test (PFT) indexes and develop predictive scores to predict PFT indexes in Chinese preoperative patients suspected with lung cancer. Preoperative patients suspected with lung cancer aged 18 years or more and examined by chest CT scan and PET were consecutively recruited from April to August 2020, at Yunnan Cancer Hospital. CT and PET data were selected from medical record. Pearson correlation was used to explore the relationships between CT parameters and PFT indexes. Predictive scores of PFT indexes were developed from unstandardized coefficients of linear regression models of using CT parameters as predictors. The assessments of predictive ability of scores were conducted by receiver operating characteristics curves. A total of 124 preoperative patients suspected with lung cancer participated in this study. Total lung volume significantly correlated with total lung capacity (r = 0.708), residual volume (r = 0.411), forced expiratory volume in one second (FEV1, r = 0.535), forced vital capacity (FVC, r = 0.687), and FEV1/FVC (r = -0.319). Percent of low attenuation volume significantly correlated with total lung capacity (r = 0.200), residual volume (r = 0.215), FEV1 percentage of predictive value (FEV1%, r = -0.204) and FEV1/FVC (r = -0.345). Four predictive scores for FEV1, FEV1%, FEV1/FVC and FVC% were developed. The area under the curve of receiver operating characteristics for FEV1 <2L, FEV1% <80%, FEV1/FVC <80% and FVC% <80% were 0.856, 0.667, 0.749 and 0.715, respectively. A prediction of poor lung function in preoperative patients suspected with lung cancer, using total lung volume and percent of low attenuation volume was possible. The predictive scores should be further evaluated for external validity.

Long COVID in Young Patients: Impact on Lung Volume Evaluated Using Multidetector CT.

PURPOSE: To evaluate using quantitative analysis on chest CT images a possible lung volume reduction in Long COVID patients who complain mild respiratory symptoms, with chest CT negative for inflammatory findings. MATERIALS AND METHODS: CT images of patients from 18 to 40 years old who underwent chest CT scan at our institution were analyzed retrospectively, using AwServer Thoracic VCAR software for a quantitative study. Exclusion criteria were inflammatory findings at CT, previous lung surgery, lung cancer, and breath artifacts that invalidate the quality of images. Patients were divided into two groups: in the first one ("post-COVID") were patients who had previous SARS-CoV-2 infection, confirmed by an RT-PCR, who underwent chest CT from 3 to 6 months after their negativization for long COVID symptoms; in the control group ("non-COVID"), were enrolled patients who underwent a chest CT scan from January 2018 to December 2019, before the spread of COVID in Italy. RESULTS: Our final population included 154 TC, 77 post-COVID patients (mean age 33 ± 6) and 77 non-COVID patients (mean age 33 ± 4.9). Non statistical significative differences were obtained between groups in terms of age, sex, and other characteristics that affect total lung capacity such as obesity, thoracic malformations, and smoking habit. Mean values of the total lung volume (TV), right-lung volume (RV), and left-lung volume (LV) in the post-COVID group compared with non-COVID group were, respectively: 5.25 ± 0.25 L vs. 5.72 ± 0.26 L (p = 0.01); 2.76 ± 0.14 L vs. 3 ± 0.14 L (p = 0.01); 2.48 ± 0.12 L vs. 2.72 ± 0.12 L (p = 0.01). CONCLUSION: In patients with symptoms suggesting Long COVID and negative chest CT macroscopic findings, quantitative volume analysis demonstrated a mean value of reduction in lung volume of 10% compared to patients of the same age who never had COVID. A chest CT negative for inflammatory findings may induce clinicians to attribute Long COVID mild respiratory symptoms to anxiety, especially in young patients. Our study brings us beyond appearances and beyond the classic radiological signs, introducing a quantitative evaluation of lung volumes in these patients. It is hard to establish to what extent this finding may contribute to Long COVID symptoms, but this is another step to gain a wider knowledge of the potential long-term effects caused by this new virus.

Influence of Paraspinal Growth-Friendly Spinal Implants in Children with Spinal Muscular Atrophy on Parasol Deformity, Rib-Vertebral Angles, Thoracic, and Lung Volumes.

INTRODUCTION: Children with spinal muscular atrophy (SMA) and progressive neuromuscular scoliosis often require early growth-friendly spinal implant (GFSI) treatment for deformity correction with implant fixation either through pedicle screws or bilateral to the spine using ribto pelvis fixation. It has been proposed that the latter fixation may change the collapsing parasol deformity via changes in the rib-vertebral angle (RVA) with a positive effect on thoracic and lung volume. The purpose of this study was to analyze the effect of paraspinal GFSI with bilateral rib-to-pelvis fixation on the parasol deformity, RVA, thoracic, and lung volumes. METHODS: SMA children with (n = 19) and without (n = 18) GFSI treatment were included. Last follow-up was before definite spinal fusion at puberty. Scoliosis and kyphosis angles, parasol deformity, and index, as well as convex and concave RVA, were measured on radiographs, whereas computed tomography images were used to reconstruct thoracic and lung volumes. RESULTS: In all SMA children (n = 37; with or without GFSI), convex RVA was smaller than concave values at all times. GFSI did not crucially influence the RVA over the 4.6-year follow-up period. Comparing age- and disease-matched adolescents with and without prior GFSI, no effect of GFSI treatment could be detected on either RVA, thoracic, or lung volumes. Parasol deformity progressed over time despite GFSI. CONCLUSION: Despite different expectations, implantation of GFSI with bilateral rib-to-pelvis fixation did not positively influence parasol deformity, RVA and/or thoracic, and lung volumes in SMA children with spinal deformity directly and over time.

Fetal lung MRI and features predicting post-natal outcome: a scoping review of the current literature.

The outcome for infants with fetal lung pathologies not only depends on the nature of the pathology, but the impact it has on the developing lungs. The main prognostic factor is the degree of pulmonary hypoplasia, but this is not detectable pre-natally. Imaging techniques aim to simulate these features with a variety of surrogate measurements, including lung volume and MRI signal intensity. Despite the complexity of the various research studies and lack of consistent methodology, this scoping review aims to summarise current applications, and promising techniques requiring further investigation.

Predicted versus CT-derived total lung volume in a general population: The ImaLife study.

Predicted lung volumes based on the Global Lung Function Initiative (GLI) model are used in pulmonary disease detection and monitoring. It is unknown how well the predicted lung volume corresponds with computed tomography (CT) derived total lung volume (TLV). The aim of this study was to compare the GLI-2021 model predictions of total lung capacity (TLC) with CT-derived TLV. 151 female and 139 male healthy participants (age 45-65 years) were consecutively selected from a Dutch general population cohort, the Imaging in Lifelines (ImaLife) cohort. In ImaLife, all participants underwent low-dose, inspiratory chest CT. TLV was measured by an automated analysis, and compared to predicted TLC based on the GLI-2021 model. Bland-Altman analysis was performed for analysis of systematic bias and range between limits of agreement. To further mimic the GLI-cohort all analyses were repeated in a subset of never-smokers (51% of the cohort). Mean±SD of TLV was 4.7±0.9 L in women and 6.2±1.2 L in men. TLC overestimated TLV, with systematic bias of 1.0 L in women and 1.6 L in men. Range between limits of agreement was 3.2 L for women and 4.2 L for men, indicating high variability. Performing the analysis with never-smokers yielded similar results. In conclusion, in a healthy cohort, predicted TLC substantially overestimates CT-derived TLV, with low precision and accuracy. In a clinical context where an accurate or precise lung volume is required, measurement of lung volume should be considered.

Feasibility of dynamic chest radiography to calculate lung volumes in adult people with cystic fibrosis: a pilot study.

INTRODUCTION: Dynamic chest radiography (DCR) is a novel, low-dose, real-time digital imaging system where software identifies moving thoracic structures and can automatically calculate lung areas. In an observational, prospective, non-controlled, single-centre pilot study, we compared it with whole-body plethysmography (WBP) in the measurement of lung volume subdivisions in people with cystic fibrosis (pwCF). METHODS: Lung volume subdivisions were estimated by DCR using projected lung area (PLA) during deep inspiration, tidal breathing and full expiration, and compared with same-day WBP in 20 adult pwCF attending routine review. Linear regression models to predict lung volumes from PLA were developed. RESULTS: Total lung area (PLA at maximum inspiration) correlated with total lung capacity (TLC) (r=0.78, p<0.001), functional residual lung area with functional residual capacity (FRC) (r=0.91, p<0.001), residual lung area with residual volume (RV) (r=0.82, p=0.001) and inspiratory lung area with inspiratory capacity (r=0.72, p=0.001). Despite the small sample size, accurate models were developed for predicting TLC, RV and FRC. CONCLUSION: DCR is a promising new technology that can be used to estimate lung volume subdivisions. Plausible correlations between plethysmographic lung volumes and DCR lung areas were identified. Further studies are needed to build on this exploratory work in both pwCF and individuals without CF. TRIAL REGISTRATION NUMBER: ISRCTN64994816.

Work of breathing and lung volume during forward leaning supported by the upper limbs.

This study compared work of breathing (WOB) and the pressure time product (PTP) to verify whether WOB and PTP decrease in the forward-leaning posture compared with erect sitting. Seven healthy adults (two females and five males) adopted three sitting postures: upright, and two forward-leaning postures of 15° and 30°. The WOB was obtained using the modified Campbell diagram, and PTP was calculated as the time integral of the area between esophageal and chest wall pressure. End-expiratory lung volume and transpulmonary pressure were significantly increased in the 15° and 30° forward-leaning postures compared with erect sitting (p â‰¦ 0.05). End-inspiratory lung volume was significantly increased in the 30° forward-leaning posture compared to erect sitting (p â‰¦ 0.05). PTP and inspiratory resistive WOB were significantly lower in the 15° and 30° forward-leaning postures compared to erect sitting (p â‰¦ 0.05). Forward leaning increases lung volume, which may dilate the airways, decrease resistant WOB, and reduce respiratory muscle activity.

Respiratory Mechanics: Revisiting the Appraisement of Lung Recruitment.

Mechanical ventilation has long been recognized as the most vital therapy for patients with ARDS. Compared with lung-protective ventilation, debates that involve the open lung strategy, which consists primarily of the lung recruitment maneuver and higher PEEP, have never been resolved. In terms of the beneficial and detrimental effects of this aggressive maneuver, appraisal of lung recruitment is essential for intensivists to make clinical decisions. This review aimed to clarify how to assess the potential for lung recruitment based on respiratory mechanics when using the pressure-volume curve or loop method and end-expiratory lung volume-static compliance of the respiratory system method. However, their limitations related to excessive generalization, accuracy, and identification of cutoff values cannot be omitted. Finally, future studies are warranted to combine these classic methods with newly invented techniques to achieve safer and more effective lung recruitment.

Estimating Preterm Lung Volume: A Comparison of Lung Ultrasound, Chest Radiography, and Oxygenation.

OBJECTIVE: To determine the relationship between lung ultrasound (LUS) examination, chest radiograph (CXR), and radiographic and clinical evaluations in the assessment of lung volume in preterm infants. STUDY DESIGN: In this prospective cohort study LUS was performed before CXR on 70 preterm infants and graded using (1) a LUS score, (2) an atelectasis score, and (3) measurement of atelectasis depth. Radiographic diaphragm position and radio-opacification were used to determine global and regional radiographic atelectasis. The relationship between LUS, CXR, and oxygenation was assessed using receiver operator characteristic and correlation analysis. RESULTS: LUS scores, atelectasis scores, and atelectasis depth did not correspond with radiographic global atelectasis (area under receiver operator characteristics curves, 0.54 [95% CI, 0.36-0.71], 0.49 [95% CI, 0.34-0.64], and 0.47 [95% CI, 0.31-0.64], respectively). Radiographic atelectasis of the right upper, right lower, left upper, and left lower quadrants was predicted by LUS scores (0.75 [95% CI, 0.59-0.92], 0.75 [95% CI, 0.62-0.89], 0.69 [95% CI, 0.56-0.82], and 0.63 [95% CI, 0.508-0.751]) and atelectasis depth (0.66 [95% CI, 0.54-0.78], 0.65 [95% CI, 0.53-0.77], 0.63 [95% CI, 0.50-0.76], and 0.56 [95% CI, 0.44-0.70]). LUS findings were moderately correlated with oxygen saturation index (ρ = 0.52 [95% CI, 0.30-0.70]) and saturation to fraction of inspired oxygen ratio (ρ = -0.63 [95% CI, -0.76 to -0.46]). The correlation between radiographic diaphragm position, the oxygenation saturation index, and peripheral oxygen saturation to fraction of inspired oxygen ratio was very weak (ρ = 0.36 [95% CI, 0.11-0.59] and ρ = -0.32 [95% CI, -0.53 to -0.07], respectively). CONCLUSIONS: LUS assessment of lung volume does not correspond with radiographic diaphragm position preterm infants. However, LUS predicted radiographic regional atelectasis and correlated with oxygenation. The relationship between radiographic diaphragm position and oxygenation was very weak. Although LUS may not replace all radiographic measures of lung volume, LUS more accurately reflects respiratory status in preterm infants. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12621001119886.

Characterization of Suboptimal Responses to Fetoscopic Endoluminal Tracheal Occlusion in Congenital Diaphragmatic Hernia.

INTRODUCTION: The aim of the study was to characterize the changes in fetal lung volume following fetoscopic endoluminal tracheal occlusion (FETO) that are associated with infant survival and need for extracorporeal membrane oxygenation (ECMO) in congenital diaphragmatic hernia (CDH). METHODS: Fetuses with CDH who underwent FETO at a single institution were included. CDH cases were reclassified by MRI metrics [observed-to-expected total lung volume (O/E TLV) and percent liver herniation]. The percent changes of MRI metrics after FETO were calculated. ROC-derived cutoffs of these changes were derived to predict infant survival to discharge. Regression analyses were done to determine the association between these cutoffs with infant survival and ECMO need, adjusted for site of CDH, gestational age at delivery, fetal sex, and CDH severity. RESULTS: Thirty CDH cases were included. ROC analysis demonstrated that post-FETO increases in O/E TLV had an area under the curve of 0.74 (p = 0.035) for the prediction of survival to hospital discharge; a cutoff of less than 10% was selected. Fetuses with a <10% post-FETO increase in O/E TLV had lower survival to hospital discharge [44.8% vs. 91.7%; p = 0.018] and higher ECMO use [61.1% vs. 16.7%; p = 0.026] compared to those with an O/E TLV increase ≥10%. Similar results were observed when the analyses were restricted to left-sided CDH cases. A post-FETO <10% increase in O/E TLV was independently associated with lower survival at hospital discharge (aOR: 0.073, 95% CI: 0.008-0.689; p = 0.022) and at 12 months of age (aOR: 0.091, 95% CI: 0.01-0.825; p = 0.036) as well as with higher ECMO use (aOR: 7.88, 95% CI: 1.31-47.04; p = 0.024). CONCLUSION: Fetuses with less than 10% increase in O/E TLV following the FETO procedure are at increased risk for requiring ECMO and for death in the postnatal period when adjusted for gestational age at delivery, CDH severity, and other confounders.

Improvement of pulmonary function and reconstructed 3D lung volume after deformity correction for thoracic spinal posttubercular kyphosis: a multicenter study.

OBJECTIVE: The aim of this study was to investigate the influence of corrective surgery on thoracic spinal posttubercular kyphosis (PTK) with respect to lung volume and pulmonary function. METHODS: This was a retrospective study of 126 patients (72 males and 54 females) who underwent posterior vertebral column resection (PVCR) for severe thoracic spinal PTK between September 2013 and June 2020. The patients' spinal parameters, results of their pulmonary function test (PFT), and CT-based 3D lung volume were recorded and analyzed preoperatively and at final follow-up. The correlation of kyphosis correction with the PFT and lung volume was evaluated. RESULTS: The mean local kyphosis decreased from 112.5° to 37.2°, and the mean local scoliosis decreased from 20.9° to 5.2°; C2-7 lordosis, thoracic kyphosis, and lumbar lordosis also significantly improved after surgery. The mean CT-based lung volume significantly increased from 2.9 L preoperatively to 3.6 L at the final follow-up. The indices of PFT, including forced vital capacity (FVC), percent predicted FVC, total lung capacity, and forced expiratory volume in 1 second, were also significantly improved, and 60 patients with pulmonary dysfunction recovered to normal at the final follow-up. The correlation analysis revealed that the correction of local kyphosis was closely correlated with the improvement in PFT and the increase in lung volume. CONCLUSIONS: PVCR cannot only effectively realign the spine in patients with severe thoracic spinal PTK deformity but also significantly improve pulmonary function. Adequate local kyphosis correction should be highly valued, as it is a key factor in increasing lung volume.

Evaluating the Use of CT-Derived Lung Volumes in Donor-Recipient Lung Size Matching for Lung Transplantation in Patients With Interstitial Lung Disease and/or Idiopathic Pulmonary Fibrosis.

PURPOSE: This study aims to assess the efficacy of current measurement strategies for lung sizing and the feasibility of future use of computed tomography (CT)-derived lung volumes to predict a donor-recipient lung size match during bilateral lung transplants. METHODS: We reviewed the data of 62 patients who underwent bilateral lung transplantation for interstitial lung disease and/or idiopathic pulmonary fibrosis from 2018 to 2019. Data for recipients was retrieved from the department's transplant database and medical records, and the donor's data was retrieved from the DonorNet. The data included demographic data, lung heights, measured total lung capacity (TLC) from plethysmography for recipients and estimated TLC for donors, clinical data, and CT-derived lung volumes in both pre- and post-transplant recipients. The post-transplant CT-derived lung volume in recipients was used as a surrogate for donor lung CT volumes due to inadequate or poor donor CT data. Computed tomography-derived lung volumes were calculated using thresholding, region growing, and cutting techniques on Computer-Aided Design and Mimics (Materialise NV, Leuven, Belgium) programs. Preoperative CT-derived lung volumes in recipients were compared with the plethysmography TLC, Frustum Model, and donor-predicted TLC. The ratio of the recipient's pre-and postoperative CT-derived volumes, the ratio of preoperative CT-derived lung volume, and donor-estimated TLC were studied to detect a correlation with 1-year outcomes. RESULTS: The recipient preoperative CT-derived volume correlated with the recipient preoperative plethysmography TLC (Pearson correlation coefficient [PCC] of 0.688) and with the recipient Frustum model volume (PCC of 0.593). The recipient postoperative CT-derived volume correlated with the recipient's postoperative plethysmography TLC (PCC of 0.651). There was no statistically significant correlation between recipients' CT-derived pre- or postoperative volume with donor-estimated TLC. The ratio of preoperative CT-derived volume to donor-estimated TLC correlated inversely with the length of ventilation (P value = .0031). The ratio of postoperative CT-derived volume to preoperative CT-derived volume correlated inversely with delayed sternal closure (P = .0039). No statistically significant correlations were found in evaluating outcomes related to lung oversizing in the recipient (defined as a postoperative to preoperative CT-derived lung volume ratio of >1.2). CONCLUSIONS: Generating CT-derived lung volumes is a valid and convenient method for evaluating lung volumes for transplantation in patients with ILD and/or IPF. Donor-estimated TLC should be interpreted carefully. Further studies should derive donor lung volumes from CT scans for a more accurate evaluation of lung size matching.

Prediction of respiratory complications by quantifying lung contusion volume using chest computed tomography in patients with chest trauma.

Pulmonary contusion is an important risk factor for respiratory complications in trauma patients. Hence, we aimed to determine the relationship between the ratio of pulmonary contusion volume to the total lung volume and patient outcomes and the predictability of respiratory complications. We retrospectively included 73 patients with a pulmonary contusion on chest computed tomography (CT) from 800 patients with chest trauma admitted to our facility between January 2019 and January 2020. Chest injury severity was expressed as the ratio of pulmonary contusion volume to total lung volume by quantifying pulmonary contusion volume on chest CT. The cut-off value was 80%. Among the 73 patients with pulmonary contusion (77% males, mean age: 45.3 years), 28 patients had pneumonia, and five had acute respiratory distress syndrome. The number of patients in the severe risk group with > 20% of pulmonary contusion volume was 38, among whom 23 had pneumonia. For predicting pneumonia, the area under the receiver operating characteristic curves for the ratio of pulmonary contusion volume was 0.85 (95% confidence interval 0.76-0.95, p = 0.008); the optimal threshold was 70.4%. Quantifying pulmonary contusion volume using initial CT enables identifying patients with chest trauma at high risk of delayed respiratory complications.

Assessment of cardiopulmonary manifestations and its correlation with semi-quantitative scoring of high-resolution computed tomography in patients with autoimmune rheumatic diseases.

PURPOSE: Autoimmune rheumatic diseases (ARD) are groups of diseases that are commonly associated with cardiac and pulmonary manifestations and may affect the morbidity and mortality of the patients. The study aimed to the assessment of cardiopulmonary manifestations and their correlation with the semi-quantitative scoring of high-resolution computed tomography (HRCT) in ARD patients. METHODS AND PATIENTS: 30 patients with ARD were included in the study (mean age 42.2 ± 9.76 years) [10 patients were scleroderma (SSc), 10 patients were rheumatoid arthritis (RA), and 10 patients were systemic lupus erythematosus (SLE)]. They all met the diagnostic criteria of the American College of Rheumatology and underwent spirometry, echocardiography, and chest HRCT. The HRCT was assessed by a semi-quantitative score for parenchymal abnormalities. Correlation between HRCT lung scores and: inflammatory markers, lung volumes in spirometry, and echocardiographic indices has been performed. RESULTS: The total lung score (TLS) by HRCT was 14.8 ± 8.78 (mean ± SD), ground glass opacity score (GGO) was 7.20 ± 5.79 (mean ± SD) and fibrosis lung score (F) was 7.63 ± 6.05 (mean ± SD). TLS correlated significantly with ESR (r 0.528, p 0.003), CRP (r 0.439, p 0.015), PaO2 (r -0.395, P 0.031) FVC% (r -0.687, p 0.001), and echocardiographic Tricuspid E (r -0.370, p 0.044), Tricuspid E/è (r -0.397,p 0.03), ESPAP (r 0.459,p 0.011), TAPSE (r -0.405, p 0.027), MPI-TDI (r -0.428, p 0.018) and RV Global strain(r -0.567, p 0.001). GGO score correlated significantly with ESR (r 0.597, p 0.001), CRP (r 0.473, p 0.008), FVC% (r -0.558, p 0.001), and RV Global strain(r -0.496, p 0.005). F score correlated significantly with FVC% (r -0.397, p 0.030), Tricuspid E/è (r -0.445, p 0.014), ESPAP (r 0.402, p 0.028), and MPI-TDI (r -0.448, p 0.013). CONCLUSION: The total lung score and GGO score in ARD were found to be consistently significantly correlated with FVC% predicted, PaO2, inflammatory markers, and RV functions. Fibrotic score correlated with ESPAP. Therefore, in a clinical setting, most clinicians who monitor patients suffering from ARD should concern with the applicability of semiquantitative HRCT scoring in clinical practice.

Direct estimation of regional lung volume change from paired and single CT images using residual regression neural network.

BACKGROUND: Chest computed tomography (CT) enables characterization of pulmonary diseases by producing high-resolution and high-contrast images of the intricate lung structures. Deformable image registration is used to align chest CT scans at different lung volumes, yielding estimates of local tissue expansion and contraction. PURPOSE: We investigated the utility of deep generative models for directly predicting local tissue volume change from lung CT images, bypassing computationally expensive iterative image registration and providing a method that can be utilized in scenarios where either one or two CT scans are available. METHODS: A residual regression convolutional neural network, called Reg3DNet+, is proposed for directly regressing high-resolution images of local tissue volume change (i.e., Jacobian) from CT images. Image registration was performed between lung volumes at total lung capacity (TLC) and functional residual capacity (FRC) using a tissue mass- and structure-preserving registration algorithm. The Jacobian image was calculated from the registration-derived displacement field and used as the ground truth for local tissue volume change. Four separate Reg3DNet+ models were trained to predict Jacobian images using a multifactorial study design to compare the effects of network input (i.e., single image vs. paired images) and output space (i.e., FRC vs. TLC). The models were trained and evaluated on image datasets from the COPDGene study. Models were evaluated against the registration-derived Jacobian images using local, regional, and global evaluation metrics. RESULTS: Statistical analysis revealed that both factors - network input and output space - were significant determinants for change in evaluation metrics. Paired-input models performed better than single-input models, and model performance was better in the output space of FRC rather than TLC. Mean structural similarity index for paired-input models was 0.959 and 0.956 for FRC and TLC output spaces, respectively, and for single-input models was 0.951 and 0.937. Global evaluation metrics demonstrated correlation between registration-derived Jacobian mean and predicted Jacobian mean: coefficient of determination (r2 ) for paired-input models was 0.974 and 0.938 for FRC and TLC output spaces, respectively, and for single-input models was 0.598 and 0.346. After correcting for effort, registration-derived lobar volume change was strongly correlated with the predicted lobar volume change: for paired-input models r2 was 0.899 for both FRC and TLC output spaces, and for single-input models r2 was 0.803 and 0.862, respectively. CONCLUSIONS: Convolutional neural networks can be used to directly predict local tissue mechanics, eliminating the need for computationally expensive image registration. Networks that use paired CT images acquired at TLC and FRC allow for more accurate prediction of local tissue expansion compared to networks that use a single image. Networks that only require a single input image still show promising results, particularly after correcting for effort, and allow for local tissue expansion estimation in cases where multiple CT scans are not available. For single-input networks, the FRC image is more predictive of local tissue volume change compared to the TLC image.

Changes in Pulmonary Functions of Adolescents with Pectus Excavatum Throughout the Nuss Procedure.

BACKGROUND: We aimed to determine the longitudinal changes in pulmonary functions of adolescents with Pectus Excavatum who underwent the Nuss procedure, the minimally invasive repair of pectus excavatum (MIRPE). METHODS: Lung function measurements were performed before bar implantation (T0), at least six weeks to ten months after implantation (T1a), at least eleven months to sixty-one months after bar implantation (T1b) and at least two weeks after bar explantation (T2). RESULTS: Data of 114 patients (83.3% male) whose median age at implantation was 15.6 years and at explantation 18.7 years were analyzed. Shortly after implantation at T1a a significant decline of vital capacity (VC; n = 82), forced vital capacity (FVC; n = 78) and forced expiratory volume in 1 second (FEV1; n = 80) compared to T0 was seen. At T1b a significant decline for the residual volume (RV; n = 83), the residual volume/total lung capacity ratio (RV/TLC; n = 81), the total specific airway resistance (sRaw; n = 80) and the total airway resistance (Raw; n = 84) also compared to T0 was measured. In the comparison of T1b to T2 a significant increase of VC, FVC (n = 67), FEV1 (n = 69), TLC (n = 67) and a significant decrease of Raw (n = 66), sRaw, RV (n = 65) and the RV/TLC (n = 64) ratio could be observed. In the direct analysis between T0 and T2, after the explantation of the bar a significant increase in VC (n = 54), FVC (n = 52), and TLC (n = 55) and a significant decrease of RV (n = 51) and the RV/TLC index (n = 50), and in airway resistance parameters like Raw (n = 52) and sRaw (n = 51) could be detected. CONCLUSIONS: Lung function values along with markers of airway resistance improve in patients after the complete procedure of MIRPE. LEVEL OF EVIDENCE: Level II.

Prevalence of restrictive lung function in children and adults in the general population.

BACKGROUND: Restrictive lung function (RLF) is characterized by a reduced lung expansion and size. In the absence of lung volume measurements, restriction can be indirectly assessed with restrictive spirometric patterns (RSP) by spirometry. Prevalence data on RLF by the golden standard body plethysmography in the general population are scarce. Therefore, we aimed to evaluate the prevalence of RLF and RSP in the general population by body plethysmography and to determine factors influencing RLF and RSP. METHODS: Pre-bronchodilation lung function data of 8891 subjects (48.0% male, age 6-82 years) have been collected in the LEAD Study, a single-centered, longitudinal, population-based study from Vienna, Austria. The cohort was categorized in the following groups based on the Global Lung Initiative reference equations: normal subjects, RLF (TLC < lower limit of normal (LLN)), RSP (FEV1/FVC ≥ LLN and a FVC < LLN), RSP only (RSP with TLC ≥ LLN). Normal subjects were considered those with FEV1, FVC, FEV1/FVC and TLC between LLN and ULN (upper limit of normal). RESULTS: The prevalence of RLF and RSP in the Austrian general population is 1.1% and 4.4%. Spirometry has a positive and negative predictive value of 18.0% and 99.6% to predict a restrictive lung function. Central obesity was associated with RLF. RSP was related to smoking and underweight. CONCLUSIONS: The prevalence of true restrictive lung function and RSP in the Austrian general population is lower than previously estimated. Our data confirm the need for direct lung volume measurement to diagnose true restrictive lung function.