Quantitative CT Analysis Research Articles

Airways abnormalities in a prospective cohort of patients with rheumatoid arthritis

Rheumatoid arthritis (RA) affects roughly 1% of the population and commonly involves the lungs. Of lung involvement in RA, interstitial lung disease (ILD) is well-known; however, airways disease in RA is relatively understudied. What are the baseline airways abnormalities in a prospective cohort of patients with RA based on pulmonary function tests (PFT), high-resolution CT scans (HRCT) and computational imaging analysis and are there associations between these abnormalities and respiratory symptoms? In this single-center study, 188 patients with RA without a clinical diagnosis of ILD underwent HRCT and PFT. Radiologists assessed HRCTs for airway abnormalities. Computational imaging via VIDA Vision software and in-house quantitative CT (qCT) analysis was applied to 147 HRCTs to quantify airway abnormalities. Airways obstruction (FEV1/FVC ratio < 0.7) was present in 20.7% of patients, and associated with older age, male sex and higher smoking rate. Radiologists identified airway abnormalities in 61% of patients-55% had bronchial wall thickening, 12% bronchiectasis, and 5% mosaic attenuation; these airways findings were associated with older age, male sex, lower FEV1, FVC, FEV1/FVC ratios, and higher rates of rheumatoid factor positivity. Prespecified qCT metrics (wall thickening % and emphysema %) correlated with PFT obstruction and more severe respiratory symptoms including shortness of breath and cough. There were high rates of airways abnormalities in this prospective RA cohort based on three methods of detection. There were significant associations between qCT measures and respiratory symptoms. Airways disease may be an under-recognized extra-articular manifestation of RA and qCT may be a sensitive method to detect the clinical impact on respiratory symptoms.

Lung Tensioning Device Coil Treatment in Patients with Severe Emphysema: A Prospective Safety and Feasibility Trial (EFFORT)

Introduction: Currently, there is a lack of bronchoscopic lung volume reduction options that do not depend on fissure integrity. Endobronchial coils have been extensively studied to address this need but exhibited variable patient response and have been discontinued. Lung tension device (LTD) coils represent the next-generation coil treatment. This study aimed to evaluate safety, feasibility, and efficacy of LTD-coil treatment. Methods: Patients with advanced emphysema and hyperinflation were enrolled at two European sites. LTD-coils (Free Flow Medical, Fremont, CA, USA) were implanted in the two most destructed lobes, as determined by quantitative CT analysis, in two separate procedures. The primary endpoint was 3-month follow-up after the last treatment. Results: Fourteen patients (50% male, median age 64 years, FEV1 23%predicted, RV 249%predicted) received LTD-coil treatment: 12 received bilateral and 2 unilateral treatment. Six serious respiratory adverse events occurred within the initial 3 months posttreatment, including one device-associated death. Treatment significantly reduced in- and expiratory volume of the treated lobes (−410 [−710, −340], p = 0.004 and −650 [−730, −190] mL, p < 0.001, respectively) and improved quality of life (SGRQ total score −4.6 [−21.0, −2.6], p < 0.001). However, at a group level, no significant improvements in pulmonary function or 6-min walk distance were observed. Responder rates ranged from 18% to 54% for the different endpoints. Conclusion: This first-in-human study shows that the new LTD-coil procedure is feasible with a safety profile comparable to the previous coil treatment. While the treatment effectively reduced lobar volume and modestly improved quality of life up to 3 months’ follow-up, at a group level it did not significantly enhance pulmonary function or exercise capacity.

Quantitative CT analysis of idiopathic pulmonary fibrosis and correlation with lung function study

BackgroundIdiopathic Pulmonary Fibrosis (IPF) is a progressive fibrotic lung disease. However, the field of quantitative CT scan analysis in conjunction with pulmonary function test for IPF patients remains relatively understudied. In this study, we evaluated the diagnostic value of features derived high-resolution computed tomography (HRCT) for patients with IPF and correlated them with pulmonary function tests.MethodsWe retrospectively analyzed the chest HRCT images and pulmonary function test results of 52 patients with IPF during the same period (1 week) and selected 52 healthy individuals, matched for sex, age, and body mass index (BMI) and with normal chest HRCT as controls. HRCT scans were performed using a Philips 256-row Brilliance iCT scanner with standardized parameters. Lung function tests were performed using a Jaeger volumetric tracer for forced vital capacity (FVC), total lung capacity (TLC), forced expiratory volume in first second (FEV1), FEV1/FVC, carbon monoxide diffusing capacity (DLCO), and maximum ventilation volume (MVV) metrics. CT quantitative analysis, including tissue segmentation and threshold-based quantification of lung abnormalities, was performed using 3D-Slicer software to calculate the percentage of normal lung areas (NL%), percentage of ground-glass opacity areas (GGO%), percentage of fibrotic area (F%) and abnormal lesion area percentage (AA%). Semi-quantitative analyses were performed by two experienced radiologists to assess disease progression. The aortic-to-sternal distance (ASD) was measured on axial images as a standardized parameter. Spearman or Pearson correlation analysis and multivariate stepwise linear regression were used to analyze the relationship between the data in each group, and the ROC curve was used to determine the optimal quantitative CT metrics for identifying IPF and controls.ResultsROC curve analysis showed that F% distinguished the IPF patient group from the control group with the largest area under the curve (AUC) of 0.962 (95% confidence interval: 0.85–0.96). Additionally, with F% = 4.05% as the threshold, the Youden’s J statistic was 0.827, with a sensitivity of 92.3% and a specificity of 90.4%. The ASD was significantly lower in the late stage of progression than in the early stage (t = 5.691, P < 0.001), with a mean reduction of 2.45% per month. Quantitative CT indices correlated with all pulmonary function parameters except FEV1/FVC, with the highest correlation coefficients observed for F% and TLC%, FEV1%, FVC%, MVV% (r = − 0.571, − 0.520, − 0.521, − 0.555, respectively, all P-values < 0.001), and GGO% was significantly correlated with DLCO% (r = − 0.600, P < 0.001). Multiple stepwise linear regression analysis showed that F% was the best predictor of TLC%, FEV1%, FVC%, and MVV% (R2 = 0.301, 0.301, 0.300, and 0.302, respectively, all P-values < 0.001), and GGO% was the best predictor of DLCO% (R2 = 0.360, P < 0.001).ConclusionsQuantitative CT analysis can be used to diagnose IPF and assess lung function impairment. A decrease in the ASD may indicate disease progression.

Clustering analysis of HRCT parameters measured using a texture-based automated system: relationship with clinical outcomes of IPF

PurposeThe extent of honeycombing and reticulation predict the clinical prognosis of IPF. Emphysema, consolidation, and ground glass opacity are visible in HRCT scans. To date, there have been few comprehensive studies that have used these parameters. We conducted automated quantitative analysis to identify predictive parameters for clinical outcomes and then grouped the subjects accordingly.MethodsCT images were obtained while patients held their breath at full inspiration. Parameters were analyzed using an automated lung texture quantification system. Cluster analysis was conducted on 159 IPF patients and clinical profiles were compared between clusters in terms of survival.ResultsKaplan-Meier analysis revealed that survival rates declined as fibrosis, reticulation, honeycombing, consolidation, and emphysema scores increased. Cox regression analysis revealed that reticulation had the most significant impact on survival rate, followed by honeycombing, consolidation, and emphysema scores. Hierarchical and K-means cluster analyses revealed 3 clusters. Cluster 1 (n = 126) with the lowest values for all parameters had the longest survival duration, and relatively-well preserved FVC and DLCO. Cluster 2 (n = 15) with high reticulation and consolidation scores had the lowest FVC and DLCO values with a predominance of female, while cluster 3 (n = 18) with high honeycombing and emphysema scores predominantly consisted of male smokers. Kaplan-Meier analysis revealed that cluster 2 had the lowest survival rate, followed by cluster 3 and cluster 1.ConclusionAutomated quantitative CT analysis provides valuable information for predicting clinical outcomes, and clustering based on these parameters may help identify the high-risk group for management.

Artificial intelligence-assisted quantitative CT analysis of airway changes following SABR for central lung tumors

IntroductionUse of stereotactic ablative radiotherapy (SABR) for central lung tumors can result in up to a 35% incidence of late pulmonary toxicity. We evaluated an automated scoring method to quantify post-SABR bronchial changes by using artificial intelligence (AI)-based airway segmentation. Materials and methodsCentral lung SABR patients treated at Amsterdam UMC (AUMC, internal reference dataset) and Peter MacCallum Cancer Centre (PMCC, external validation dataset) were identified. Patients were eligible if they had pre- and post-SABR CT scans with ≤ 1 mm resolution. The first step of the automated scoring method involved AI-based airway auto-segmentation using MEDPSeg, an end-to-end deep learning-based model. The Vascular Modeling Toolkit in 3D Slicer was then used to extract a centerline curve through the auto-segmented airway lumen, and cross-sectional measurements were computed along each bronchus for all CT scans. For AUMC patients, airway stenosis/occlusion was evaluated by both visual assessment and automated scoring. Only the automated method was applied to the PMCC dataset. ResultsStudy patients comprised 26 from AUMC, and 33 from PMCC. Visual scoring identified stenosis/occlusion in 8 AUMC patients (31 %), most frequently in the segmental bronchi. After airway auto-segmentation, minor manual edits were needed in 9 % of patients. Segmentation for a single scan averaged 83sec (range 73–136). Automated scoring nearly doubled detected airway stenosis/occlusion (n = 15, 58 %), and allowed for earlier detection in 5/8 patients who had also visually scored changes. Estimated rates were 48 % and 66 % at 1- and 2-years, respectively, for the internal dataset. The automated detection rate was 52 % in the external dataset, with 1- and 2-year risks of 56 % and 61 %, respectively. ConclusionAn AI-based automated scoring method allows for detection of more bronchial stenosis/occlusion after lung SABR, and at an earlier time-point. This tool can facilitate studies to determine early airway changes and establish more reliable airway tolerance doses.

Retrolabyrinthine approach to the lateral skull base: The value of preoperative temporal bone CT analysis

PurposeThe most used neurosurgical approach to reach cerebellar-pontine angle is the retrosigmoid route. This article describes the presigmoid approach which requires excellent knowledge of the labyrinthine block together with quantitative analysis of temporal bone CT. MethodsCT-based quantitative measurements were obtained in patients undergoing vestibular neurectomy with a presigmoid approach. Eighteen patients were enrolled, and five measures were taken: Trautmann’s area, the petro-clival angle, presigmoid dura length and its angle. The relationship between these measurements and hospitalization days, operating times, and complications was explored. ResultsThe posterior semicircilar canal (PSC)-sigmoid sinus (SS) distance, presigmoid dura- internal auditory canal (IAC)-PSC angle, and duration of surgery are predictors of complications. Specifically, a PSC-sigmoid sinus distance <11 mm, a dura presig-IAC-PSC angle <14 are associated with the highest risk of complications. ConclusionPreoperative temporal bone CT scan can guide the surgeon through the narrowest areas of the surgical approach. Trautmann’s triangle area and petro-clival angle reduction are challenging and can be faced with combined microscopic-endoscopic technique, and with optics angulation-rotation. The retrolabyrinthine approach can enable hearing preservation and minimal cerebellar retraction.

Quantitative CT Analysis of Hepatocellular Carcinoma Nodules in Liver Transplant Candidates: Impact of Volume of Interest and Contrast Phase on Recurrence Prediction

Quantitative CT Analysis of Hepatocellular Carcinoma Nodules in Liver Transplant Candidates: Impact of Volume of Interest and Contrast Phase on Recurrence Prediction

Detection of early pulmonary emphysema by multi-contrast x-ray Talbot-Lau interferometer.

Pulmonary emphysema is a part of chronic obstructive pulmonary disease, which is an irreversible chronic respiratory disease. In order to avoid further damage to lung tissue, early diagnosis and treatment of pulmonary emphysema is essential. Early pulmonary emphysema diagnosis is difficult with conventional radiographic imaging. Recently, x-ray phase contrast imaging has proved to be an effective and promising imaging strategy for soft tissue, due to its high sensitivity and multi-contrast. The aim of this study is to diagnose pulmonary emphysema early utilizing an x-ray Talbot-Lau interferometer (TLI). We successfully established the mouse model of emphysema by porcine pancreatic elastase treatment, and then used the established x-ray TLI to perform imaging experiments on the mice with different treatment time. The traditional absorption CT and phase contrast CT were obtained simultaneously through TLI. The CT results and histopathology of mice lung in different treatment time were quantitatively analyzed. By imaging mice lungs, it can be found that phase contrast has higher sensitivity than absorption contrast in early pulmonary emphysema. The results show that the phase contrast signal could distinguish the pulmonary emphysema earlier than the conventional attenuation signal, which can be consistent with histological images. Through the quantitative analysis of pathological section and phase contrast CT, it can be found that there is a strong linear correlation. In this study, we quantitatively analyze mean linear intercept of histological sections and CT values of mice. The results show that the phase contrast signal has higher imaging sensitivity than the attenuation signal. X-ray TLI multi-contrast imaging is proved as a potential diagnostic method for early pulmonary emphysema in mice.

Interstitial Lung Disease, Quantitative CT Analysis and Artificial Intelligence Applications, Radiomics

Interstitial Lung Disease, Quantitative CT Analysis and Artificial Intelligence Applications, Radiomics

Radiomics-based quantitative contrast-enhanced CT analysis of abdominal lymphadenopathy to differentiate tuberculosis from lymphoma

Radiomics-based quantitative contrast-enhanced CT analysis of abdominal lymphadenopathy to differentiate tuberculosis from lymphoma

Assessment of Treatment Response in Patients With Severe Asthma Using Visual and Quantitative Analysis of Chest CT.

To evaluate the role of visual and quantitative chest CT parameters in assessing treatment response in patients with severe asthma. Korean participants enrolled in a prospective multicenter study, named the Precision Medicine Intervention in Severe Asthma study, from May 2020 to August 2021, underwent baseline and follow-up chest CT scans (inspiration/expiration) 10-12 months apart, before and after biologic treatment. Two radiologists scored bronchiectasis severity and mucus plugging extent. Quantitative parameters were obtained from each CT scan as follows: normal lung area (normal), air trapping without emphysema (AT without emph), air trapping with emphysema (AT with emph), and airway (total branch count, Pi10). Clinical parameters, including pulmonary function tests (forced expiratory volume in 1 s [FEV1] and FEV1/forced vital capacity [FVC]), sputum and blood eosinophil count, were assessed at initial and follow-up stages. Changes in CT parameters were correlated with changes in clinical parameters using Pearson or Spearman correlation. Thirty-four participants (female:male, 20:14; median age, 50.5 years) diagnosed with severe asthma from three centers were included. Changes in the bronchiectasis and mucus plugging extent scores were negatively correlated with changes in FEV1 and FEV1/FVC (ρ = from -0.544 to -0.368, all P < 0.05). Changes in quantitative CT parameters were correlated with changes in FEV1 (normal, r = 0.373 [P = 0.030], AT without emph, r = -0.351 [P = 0.042]), FEV1/FVC (normal, r = 0.390 [P = 0.022], AT without emph, r = -0.370 [P = 0.031]). Changes in total branch count were positively correlated with changes in FEV1 (r = 0.349 [P = 0.043]). There was no correlation between changes in Pi10 and the clinical parameters (P > 0.05). Visual and quantitative CT parameters of normal, AT without emph, and total branch count may be effective for evaluating treatment response in patients with severe asthma.

Differences in the Quantitative HRCT Characteristics of Patients with Asthma, COPD and Asthma-COPD Overlap and Their Relationships with Pulmonary Function.

We compared pulmonary function indices and quantitative CT parameters of airway remodeling, air trapping, and emphysema in asthmatic patients and patients with COPD and asthma-COPD overlap (ACO) and explored their relationships with airflow limitation. Patients with asthma (n=48), COPD (n=52), and ACO (n=30) and controls (n=54) who completed pulmonary function tests and HRCT scans were retrospectively enrolled in our study. Quantitative CT analysis software was used to assess emphysema (LAA%), airway wall dimensions (wall area (WA), luminal area (LA), and wall area percentage (WA%)), and air trapping ((relative volume change of -860 HU to -950 HU (RVC-860 to-950) and the expiration-to-inspiration ratio of the mean lung density (MLDE/I))). Differences in pulmonary function and HRCT parameters were compared among the groups. Spearman correlation analysis and regression analysis were utilized to explore structure‒function relationships. The LAA% in COPD and ACO patients was significantly greater than that in asthmatic patients and controls. The WA% and WA in COPD and ACO patients were greater than those in controls, whereas the WA% and LA between asthmatic patients and controls reached statistical significance. The RVC-860 to -950 levels decreased in the following order: ACO, COPD, and asthma. RVC-860 to -950 independently predicted FEV1% in asthmatic patients; LAA% and MLDE/I in COPD patients; and LAA%, WA% and RVC-860 to -950 in ACO patients. Comparable emphysema was observed in patients with COPD and ACO but not in asthmatic patients. All patients exhibited proximal airway remodeling. The bronchi were thickened outward in COPD and ACO patients but are thickened inward in asthmatic patients. Furthermore, air trapping in ACO patients was the most severe among all the groups. Indirect lung densitometry measurements might be more predictive of the degree of airflow limitation than direct airway measurements in obstructive airway diseases.

TGF-β1 overexpression in severe COVID-19 survivors and its implications for early-phase fibrotic abnormalities and long-term functional impairment.

In post-COVID survivors, transforming growth factor-beta-1 (TGF-β1) might mediate fibroblast activation, resulting in persistent fibrosis. In this study, 82 survivors of COVID-19-associated ARDS were examined at 6- and 24-months post-ICU discharge. At 6-months, quantitative CT analysis of lung attenuation was performed and active TGF-β1 was measured in blood and exhaled breath condensate (EBC). At 6-months of ICU-discharge, patients with reduced DmCO/alveolar volume ratio exhibited higher plasma and EBC levels of active TGF-β1. Plasma TGF-β1 levels were elevated in dyspneic survivors and directly related to the high-attenuation lung volume. In vitro, plasma and EBC from survivors induced profibrotic changes in human primary fibroblasts in a TGF-β receptor-dependent manner. Finally, at 6-months, plasma and EBC active TGF-β1 levels discriminated patients who, 24-months post-ICU-discharge, developed gas exchange impairment. TGF-β1 pathway plays a pivotal role in the early-phase fibrotic abnormalities in COVID-19-induced ARDS survivors, with significant implications for long-term functional impairment.

A Multicenter Study of COPD and Cognitive Impairment: Unraveling the Interplay of Quantitative CT, Lung Function, HIF-1α, and Clinical Variables.

The exact link between cognitive impairment (CI) and chronic obstructive pulmonary disease (COPD) is still limited. Thus, we aim to find the relationship and interaction of quantitative CT (QCT), lung function, HIF-1α, and clinical factors with the development of CI among COPD patients. A cross-sectional multicentre study was conducted from January 2022 to December 2023. We collected clinical data, spirometry, CT images, and venous blood samples from 114 COPD participants. Cognitive impairment assessment using the Montreal Cognitive Assessment Indonesian version (MoCA-Ina) with a cutoff value 26. The QCT analysis consists of lung density, airway wall thickness, pulmonary artery-to-aorta ratio (PA:A), and pectoralis muscles using 3D Slicer software. Serum HIF-1α analysis was performed using ELISA. We found significant differences between %LAA-950, age, COPD duration, BMI, FEV1 pp, and FEV1/FVC among GOLD grades I-IV. Only education duration was found to correlate with CI (r = 0.40; p < 0.001). We found no significant difference in HIF-1α among GOLD grades (p = 0.149) and no correlation between HIF-1α and CI (p = 0.105). From multiple linear regression, we observed that the MoCA-Ina score was influenced mainly by %LAA-950 (p = 0.02) and education duration (p = 0.01). The path analysis model showed both %LAA and education duration directly and indirectly through FEV1 pp contributing to CI. We conclude that the utilization of QCT parameters is beneficial as it can identify abnormalities and contribute to the development of CI, indicating its potential utility in clinical decision-making. The MoCA-Ina score in COPD is mainly affected by %LAA-950 and education duration. Contrary to expectations, this study concludes that HIF-1α does not affect CI among COPD patients.

Quantitative CT Evaluation of Bone Mineral Density in the Thoracic Spine on 18F-Fluorocholine PET/CT Imaging in Patients With Primary Hyperparathyroidism

Introduction: Measurement of bone mineral density (BMD) with quantitative CT (QCT) carries several advantages over other densitometric techniques, including superior assessment of the spine. As most QCT studies evaluated the lumbar spine, measurements of the thoracic spine are limited. We performed QCT analysis of the thoracic spine in a cohort of patients with primary hyperparathyroidism. Materials and methods: This study was a retrospective QCT analysis of the thoracic spine on 18F-fluorocholine PET/CT scans in patients with primary hyperparathyroidism patients between March 2018 and December 2022. Correlations between QCT-derived BMD or Hounsfield units (HU) and demographic data, laboratory parameters, results from histopathological examination after parathyroidectomy and results of DXA imaging were analyzed, when available. Results: In 189 patients, mean QCT-derived BMD at the thoracic spine was 85.6 mg/cm3. Results from recent DXA were available in 122 patients. Mean thoracic QCT-derived BMD and HU were significantly correlated with DXA-derived BMD in lumbar spine, total hip and femoral neck and with the lowest T-score at DXA imaging. Only weak correlations were found with BMI or 18F-fluorocholine uptake, while no significant correlations were found with adenoma weight, PTH or calcium levels. Conclusion: Our study confirms correlation between QCT-derived BMD in the thoracic spine with age and DXA-derived BMD measurements within a population of patients with primary hyperparathyroidism. Establishment of reference BMD values for individual thoracic vertebrae, may allow direct osteoporosis classification on thoracic CT imaging.

How early can atherosclerosis be detected by coronary CT angiography? Insights from quantitative CT analysis of serial scans in the PARADIGM trial

BackgroundNon-obstructing small coronary plaques may not be well recognized by expert readers during coronary computed tomography angiography (CCTA) evaluation. Recent developments in atherosclerosis imaging quantitative computed tomography (AI-QCT) enabled by machine learning allow for whole-heart coronary phenotyping of atherosclerosis, but its diagnostic role for detection of small plaques on CCTA is unknown. MethodsWe performed AI-QCT in patients who underwent serial CCTA in the multinational PARADIGM study. AI-QCT results were verified by a level III experienced reader, who was blinded to baseline and follow-up status of CCTA. This retrospective analysis aimed to characterize small plaques on baseline CCTA and evaluate their serial changes on follow-up imaging. Small plaques were defined as a total plaque volume <50 ​mm3. ResultsA total of 99 patients with 502 small plaques were included. The median total plaque volume was 6.8 ​mm3 (IQR 3.5–13.9 ​mm3), most of which was non-calcified (median 6.2 ​mm3; 2.9–12.3 ​mm3). The median age at the time of baseline CCTA was 61 years old and 63% were male. The mean interscan period was 3.8 ​± ​1.6 years. On follow-up CCTA, 437 (87%) plaques were present at the same location as small plaques on baseline CCTA; 72% were larger and 15% decreased in volume. The median total plaque volume and non-calcified plaque volume increased to 18.9 ​mm3 (IQR 8.3–45.2 ​mm3) and 13.8 ​mm3 (IQR 5.7–33.4 ​mm3), respectively, among plaques that persisted on follow-up CCTA. Small plaques no longer visualized on follow-up CCTA were significantly more likely to be of lower volume, shorter in length, non-calcified, and more distal in the coronary artery, as compared with plaques that persisted at follow-up. ConclusionIn this retrospective analysis from the PARADIGM study, small plaques (<50 ​mm3) identified by AI-QCT persisted at the same location and were often larger on follow-up CCTA.

Dipeptidyl-peptidase 3 and IL-6: potential biomarkers for diagnostics in COVID-19 and association with pulmonary infiltrates

Coronavirus SARS-CoV-2 spread worldwide, causing a respiratory disease known as COVID-19. The aim of the present study was to examine whether Dipeptidyl-peptidase 3 (DPP3) and the inflammatory biomarkers IL-6, CRP, and leucocytes are associated with COVID-19 and able to predict the severity of pulmonary infiltrates in COVID-19 patients versus non-COVID-19 patients. 114 COVID-19 patients and 35 patients with respiratory infections other than SARS-CoV-2 were included in our prospective observational study. Blood samples were collected at presentation to the emergency department. 102 COVID-19 patients and 28 non-COVID-19 patients received CT imaging (19 outpatients did not receive CT imaging). If CT imaging was available, artificial intelligence software (CT Pneumonia Analysis) was used to quantify pulmonary infiltrates. According to the median of infiltrate (14.45%), patients who obtained quantitative CT analysis were divided into two groups (> median: 55 COVID-19 and nine non-COVID-19, ≤ median: 47 COVID-19 and 19 non-COVID-19). DPP3 was significantly elevated in COVID-19 patients (median 20.85 ng/ml, 95% CI 18.34–24.40 ng/ml), as opposed to those without SARS-CoV-2 (median 13.80 ng/ml, 95% CI 11.30–17.65 ng/ml; p < 0.001, AUC = 0.72), opposite to IL-6, CRP (each p = n.s.) and leucocytes (p < 0.05, but lower levels in COVID-19 patients). Regarding binary logistic regression analysis, higher DPP3 concentrations (OR = 1.12, p < 0.001) and lower leucocytes counts (OR = 0.76, p < 0.001) were identified as significant and independent predictors of SARS-CoV-2 infection, as opposed to IL-6 and CRP (each p = n.s.). IL-6 was significantly increased in patients with infiltrate above the median compared to infiltrate below the median both in COVID-19 (p < 0.001, AUC = 0.78) and in non-COVID-19 (p < 0.05, AUC = 0.81). CRP, DPP3, and leucocytes were increased in COVID-19 patients with infiltrate above median (each p < 0.05, AUC: CRP 0.82, DPP3 0.70, leucocytes 0.67) compared to infiltrate below median, opposite to non-COVID-19 (each p = n.s.). Regarding multiple linear regression analysis in COVID-19, CRP, IL-6, and leucocytes (each p < 0.05) were associated with the degree of pulmonary infiltrates, as opposed to DPP3 (p = n.s.). DPP3 showed the potential to be a COVID-19-specific biomarker. IL-6 might serve as a prognostic marker to assess the extent of pulmonary infiltrates in respiratory patients.

A quantitative CT analysis of fibula inlayed in a massive allograft for femoral diaphysis reconstruction

IntroductionIn diaphyseal reconstructions for bone tumor resection, massive bone allografts (MBA) are historically regarded as the gold standard. However, these are not without complications, and they present an elevated risk of infection, nonunion and structural failure that increases over time as the graft remains largely avascular. To counteract this disadvantage, a combination of allograft with a vascularized fibula has been proposed. The aim of our study was to objectively review the results of combined vascularized fibula-allograft constructs compared to plain allograft reconstruction for bone defects in tumor patients and to assess fibular vitality predictive factors from imaging studies. Materials and methodsOur data was retrospectively reviewed for patients with femoral diaphysis reconstructions in the past ten years. Ten patients (six males and four females) with a mean average follow-up time of 43.80 months (range 20–83, SD 18.17) with combined graft (Group A) were included in the study. As a control group 11 patients (six males and five females) with a mean average follow-up of 56.91 months (range 7–118, SD 41.33) with a simple allograft reconstruction were analyzed (Group B). Demographic and surgical data, adjuvant therapy as well as complications were analyzed in both groups. Both groups were assessed with plain radiographs for bony fusion at the osteotomy sites. Patients in “Group A” had consecutive CT scans at 6 months and then annually to check for potential bone stock and bone density changes. We analyzed total bone density as well as incremental changes in three different areas of the reconstruction. This was done at two defined levels for each patient. Only patients with at least two consecutive CT scans were included in the study. ResultsThere were no statistical differences between the groups in terms of demographics, diagnosis or adjuvant therapy (p = 1.0). The mean average surgical time (599.44 vs 229.09) and mean average blood loss (1855.56 ml vs. 804.55 ml) were significantly higher in the combined graft group A (p < 0.001 and p = 0.01, respectively). The mean average length of resection (19.95 cm vs. 15.50 cm) was higher in the combined graft group (p = 0.04). The risk for non-union and infectious complication was higher in the allograft group, however, the difference was not significant (p = 0.09 and p = 0.66, respectively). The mean average time to union at junction sites was 4.71 months (range 2.5–6.0, SD 1.19) for cases of successful fibula transfer, 19.50 months (range 5.5–29.5, SD 12.49) for the three cases where we presumed the fibula was not viable and 18.85 months (range 9–60, SD 11.99) for the allograft group. The difference in healing time was statistically significant (p = 0.009). There were four cases of non-union in the allograft group.Seven out of ten patients in Group A exhibited incremental changes in all CT scan measured values. This difference was statistically significant already at 18 months from the index surgery (p = 0.008). The patients with a non-viable fibula had a smaller increase in the percentage of total bone density area measured in the CT scan compared to those patients with a successful fibula transfer (4.33, SD 2.52 vs. 52.29, SD 22.74, p = 0.008). The average bone density incremental increase in-between the fibula and allograft was different among patients with an unsuccessful fibula transfer (32.22, SD 10.41) and the ones with a viable fibula (288.00, SD123.74, p = 0.009). Bony bridges were observed in six cases of viable fibula and in none of the tree presumably dead fibulas (p = 0.03). The mean average MSTS score was higher for the subgroup of successful fibular transfer (26.7/30, SD 2.87) when compared to the group of non-viable fibular graft (17.00/30, SD 6.08) and this was also statistically significant (p = 0–007). ConclusionA viable fibula enhances incorporation of the allograft and decreases the risk for both structural failure as well as infectious complications. Viable fibula also contributes to better functional status of the recipient. Consecutive CT scans proved to be a reliable method for assessing fibular vitality. When no measurable changes are present at 18-month follow-up, we can declare the transfer unsuccessful with a good amount of certainty. These reconstructions behave as simple allograft reconstructions with analogue risk factors. The presence of either axial bridges between the fibula and allograft or newly formed bone on the inner surface of the allograft is indicative of a successful fibular transfer. The success rate of fibular transfer in our study was only 70% and skeletally mature and taller patients seem to be at increased risk for failure. The longer surgical times and donor site morbidity therefore warrant stricter indications for this procedure.

Quantitative CT Analysis Based on Smoking Habits and Chronic Obstructive Pulmonary Disease in Patients with Normal Chest CT.

To assess normal CT scans with quantitative CT (QCT) analysis based on smoking habits and chronic obstructive pulmonary disease (COPD). From January 2013 to December 2014, 90 male patients with normal chest CT and quantification analysis results were enrolled in our study [non-COPD never-smokers (n = 38) and smokers (n = 45), COPD smokers (n = 7)]. In addition, an age-matched cohort study was performed for seven smokers with COPD. The square root of the wall area of a hypothetical bronchus of internal perimeter 10 mm (Pi10), skewness, kurtosis, mean lung attenuation (MLA), and percentage of low attenuation area (%LAA) were evaluated. Among patients without COPD, the Pi10 of smokers (4.176 ± 0.282) was about 0.1 mm thicker than that of never-smokers (4.070 ± 0.191, p = 0.047), and skewness and kurtosis of smokers (2.628 ± 0.484 and 6.448 ± 3.427) were lower than never-smokers (2.884 ± 0.624, p = 0.038 and 8.594 ± 4.944, p = 0.02). The Pi10 of COPD smokers (4.429 ± 0.435, n = 7) was about 0.4 mm thicker than never-smokers without COPD (3.996 ± 0.115, n = 14, p = 0.005). There were no significant differences in MLA and %LAA between groups (p > 0.05). Even on normal CT scans, QCT showed that the airway walls of smokers are thicker than never-smokers regardless of COPD and it preceded lung parenchymal changes.

Medium-long term prognosis prediction for idiopathic pulmonary fibrosis patients based on quantitative analysis of fibrotic lung volume

PurposeTo investigate the prognostic value of quantitative analysis of CT among patients with idiopathic pulmonary fibrosis (IPF) by quantifying the fibrosis extent and to attempt to provide precise medium-long term prognostic predictions for individual patients.MethodsThis was a retrospective cohort study that included 95 IPF patients in Zhongshan Hospital, Fudan University. 64 patients firstly diagnosed with IPF from 2009 to 2015 was included as the derivation cohort. Information regarding sex, age, the Gender-Age-Physiology (GAP) index, high-resolution computed tomography (HRCT) images, survival status, and pulmonary function parameters including forced vital capacity (FVC), FVC percent predicted (FVC%pred), diffusing capacity of carbon monoxide (DLCO), DLCO percent predicted (DLCO%pred), carbon monoxide transfer coefficient (KCO), KCO percent predicted (KCO%pred) were collected. 31 patients were included in the validation cohort. The Synapse 3D software was used to quantify the fibrotic lung volume (FLV) and total lung volume (TLV). The ratio of FLV to TLV was calculated and labeled CTFLV/TLV%, reflecting the extent of fibrosis. All the physiological variants and CTFLV/TLV% were analyzed for the dimension of survival through both univariate analysis and multivariate analysis. Formulas for predicting the probability of death based on the baseline CTFLV/TLV% were calculated by logistic regression, and validated by the validation cohort.ResultsThe univariate analysis indicated that CTFLV/TLV% along with DLCO%pred, KCO%pred and GAP index were significantly correlated with survival. However, only CTFLV/TLV% was meaningful in the multivariate analysis for prognostic prediction (HR 1.114, 95% CI 1.047–1.184, P = 0.0006), and the best cutoff was 11%, based on receiver operating characteristic (ROC) curve analysis. The survival times for the CTFLV/TLV% ≤ 11% and CTFLV/TLV% > 11% groups were significantly different. Given the CTFLV/TLV% data, the death probability of a patient at 1 year, 3 years and 5 years could be calculated by using a particular formula. The formulas were tested by the validation cohort, showed high sensitivity (88.2%), specificity (92.8%) and accuracy (90.3%).ConclusionQuantitative volume analysis of CT might be useful for evaluating the extent of fibrosis in the lung. The CTFLV/TLV% could be a valuable biomarker for precisely predicting the medium-long term prognosis of individual patients with IPF.