Refined scan protocol for the evaluation of pulmonary perfusion standardized image quality and reduced radiation dose in dynamic chest radiography

PURPOSE

Dynamic chest radiography (DCR) is a novel imaging technique used to noninvasively evaluate pulmonary perfusion. However, the standard DCR protocol, which is roughly adapted to the patient's body size, occasionally causes over- or underexposure, which could influence clinical evaluation. Therefore, we proposed a refined protocol by increasing the number of patient body mass index (BMI) categories from three to seven groups and verified its usefulness by comparing the image sensitivity indicators (S-values) and entrance surface doses (ESDs) of the conventional protocol with those of our refined protocol.

METHODS

This retrospective observational study included 388 datasets (standing position, 224; supine position, 164) for the conventional protocol (December 2019-April 2021) and 336 datasets (standing position, 233; supine position, 103) for the refined protocol (June-November 2021). The conventional protocol (BMI-3 protocol) divided the patients into three BMI groups (BMI < 17, 17≤BMI < 25, and BMI ≥ 25 kg/m2 ), whereas the refined protocol (BMI-7 protocol) divided the patients into seven BMI groups (BMI < 17, 17 ≤ BMI < 20, 20 ≤ BMI < 23, 23 ≤ BMI < 26, 26 ≤ BMI < 29, 29 ≤ BMI < 32, and BMI ≥ 32 kg/m2 ). The coefficients of variation (CVs) for the S-values and ESDs acquired using the two protocols were compared.

RESULTS

The CVs of the S-values in the BMI-7 protocol group were significantly lower than those in the BMI-3 protocol group for the standing (28.8% vs. 16.7%; p < 0.01) and supine (24.5% vs. 17.7%; p < 0.01) positions. The ESDs of patients scanned using the BMI-7 protocol were significantly lower than those scanned using the BMI-3 protocol in the standing (1.3 vs. 1.1 mGy; p < 0.01) and supine positions (2.5 vs. 1.6 mGy; p < 0.01), although the mean BMI of the two groups were similar.

CONCLUSION

We introduced the BMI-7 protocol and demonstrated its standardized image quality and reduced radiation exposure in patients undergoing DCR.

Prevalence and mortality associations of interstitial lung abnormalities in rheumatoid arthritis within a multicentre prospective cohort of smokers

OBJECTIVE

To investigate the prevalence and mortality impact of interstitial lung abnormalities (ILAs) in RA and non-RA comparators.

METHODS

We analysed associations between ILAs, RA, and mortality in COPDGene, a multicentre prospective cohort study of current and past smokers, excluding known interstitial lung disease (ILD) or bronchiectasis. All participants had research chest high-resolution CT (HRCT) reviewed by a sequential reading method to classify ILA as present, indeterminate or absent. RA cases were identified by self-report RA and DMARD use; non-RA comparators had neither an RA diagnosis nor used DMARDs. We examined the association and mortality risk of RA and ILA using multivariable logistic regression and Cox regression.

RESULTS

We identified 83 RA cases and 8725 non-RA comparators with HRCT performed for research purposes. ILA prevalence was 16.9% in RA cases and 5.0% in non-RA comparators. After adjusting for potential confounders, including genetics, current/past smoking and other lifestyle factors, ILAs were more common among those with RA compared with non-RA [odds ratio 4.76 (95% CI 2.54, 8.92)]. RA with ILAs or indeterminate for ILAs was associated with higher all-cause mortality compared with non-RA without ILAs [hazard ratio (HR) 3.16 (95% CI 2.11, 4.74)] and RA cases without ILA [HR 3.02 (95% CI 1.36, 6.75)].

CONCLUSIONS

In this cohort of smokers, RA was associated with ILAs and this persisted after adjustment for current/past smoking and genetic/lifestyle risk factors. RA with ILAs in smokers had a 3-fold increased all-cause mortality, emphasizing the importance of further screening and treatment strategies for preclinical ILD in RA.

Surgical diagnosis and treatment of a solitary lung nodule of IgG4-related disease, mimicking primary lung carcinoma or metastatic lung tumour: A rare case

INTRODUCTION

IgG4-related disease is a poorly understood immune disorder. Its features include tumour-like swelling of involved organs, lymphoplasmacytic infiltrate with IgG4 positive plasma cells. IgG4-related lung disease can manifest radiologically as various types of pulmonary abnormalities, including mass-like lesions and pleural effusion, and it may mimic malignant disease.

PRESENTATION OF CASE

A 76-year-old man was found to have a 4-mm ground glass opacity in the left lower lobe of the lung on follow-up chest CT after surgery for colon carcinoma. This lesion gradually became consolidated and enlarged to 9 mm over about three years. We performed a video-assisted left basal segmentectomy for the purposes of both diagnosis and treatment. Pathological examination revealed lymphoplasmacytic infiltration, mainly with IgG4-positive plasma cells.

DISCUSSION

A major characteristic of IgG4-related lung disease is multiple, small, bilateral, lung nodules and solid nodules reportedly being detected in almost all patients. However, solitary nodules are rare, being present in only 14 %. Moreover, this case shows extremely rare radiological findings in which a ground-glass opacity had gradually morphed into a solid nodule. It is difficult to differentiate IgG4-related lung nodules from other lung diseases, such as primary or metastatic lung tumours, standard interstitial pneumonia, organizing pneumonia.

CONCLUSION

We have here presented a rare case of IgG4-related lung disease with a 3-year course, including detailed radiological findings. Surgery is very useful for both diagnosis and treatment of a small, solitary, deeply located, pulmonary nodule of IgG4-related lung disease.

Efficacy of Dynamic Chest Radiography for Chronic Thromboembolic Pulmonary Hypertension

Background While current guidelines require lung ventilation-perfusion (V/Q) scanning as the first step to diagnose chronic pulmonary embolism in pulmonary hypertension (PH), its use may be limited by low availability and/or exposure to ionizing radiation. Purpose To compare the performance of dynamic chest radiography (DCR) and lung V/Q scanning for detection of chronic thromboembolic PH (CTEPH). Materials and Methods Patients with PH who underwent DCR and V/Q scanning in the supine position from December 2019 to July 2021 were retrospectively screened. The diagnosis of CTEPH was confirmed with right heart catheterization and invasive pulmonary angiography. Observer tests were conducted to evaluate the diagnostic accuracy of DCR and V/Q scanning. The lungs were divided into six areas (upper, middle, and lower for both) in the anteroposterior image, and the number of lung areas with thromboembolic perfusion defects was scored. Diagnostic performance was compared between DCR and V/Q scanning using the area under the receiver operating characteristic curve. Agreement between the interpretation of DCR and that of V/Q scanning was assessed using the Cohen kappa coefficient and percent agreement. Results A total of 50 patients with PH were analyzed: 29 with CTEPH (mean age, 64 years ± 15 [SD]; 19 women) and 21 without CTEPH (mean age, 61 years ± 22; 14 women). The sensitivity, specificity, and accuracy of DCR were 97%, 86%, and 92%, respectively, and those of V/Q scanning were 100%, 86%, and 94%, respectively. Areas under the receiver operating characteristic curve for DCR and V/Q scanning were 0.92 (95% CI: 0.79, 0.97) and 0.93 (95% CI: 0.78, 0.98). Agreement between the consensus interpretation of DCR and that of V/Q scanning was substantial (κ = 0.79 [95% CI: 0.61, 0.96], percent agreement = 0.9 [95% CI: 0.79, 0.95]). Conclusion Dynamic chest radiography had similar efficacy to ventilation-perfusion scanning in the detection of chronic thromboembolic pulmonary hypertension. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Wandtke and Koproth-Joslin in this issue.

Impact of a new deep-learning-based reconstruction algorithm on image quality in ultra-high-resolution CT: clinical observational and phantom studies

OBJECTIVES

To demonstrate the effect of an improved deep learning-based reconstruction (DLR) algorithm on Ultra-High-Resolution Computed Tomography (U-HRCT) scanners.

METHODS

Clinical and phantom studies were conducted. Thirty patients who underwent contrast-enhanced CT examination during the follow-up period were enrolled. Images were reconstructed using improved DLR [termed, New DLR, i.e., Advanced Intelligent Clear-IQ Engine (AiCE) Body Sharp] and conventional DLR (Conv DLR, AiCE Body) algorithms. Two radiologists assessed the overall image quality using a 5-point scale (5 = excellent; 1 = unacceptable). The noise power spectra (NPSs) were calculated to assess the frequency characteristics of the image noise, and the square root of area under the curve (√AUC NPS) between 0.05 and 0.50 cycle/mm was calculated as an indicator of the image noise. Dunnett's test was used for statistical analysis of the visual evaluation score, with statistical significance set at p < 0.05.

RESULTS

The overall image quality of New DLR was better than that of the Conv DLR (4.2 ± 0.4 and 3.3 ± 0.4, respectively; p < 0.0001). All New DLR images had an overall image quality score above the average or excellent. The √AUCNPS value of New DLR was lower than that of Conv DLR (13.8 and 14.2, respectively). The median values of reconstruction time required with New DLR and Conv DLR were 5.0 and 7.8 min, respectively.

CONCLUSIONS

The new DLR algorithm improved the image quality within a practical reconstruction time.

ADVANCES IN KNOWLEDGE

The new DLR enables us to choose whether to improve image quality or reduce the dose.

Interstitial Lung Abnormalities at CT: Subtypes, Clinical Significance, and Associations with Lung Cancer

Interstitial lung abnormality (ILA) is defined as an interstitial change detected incidentally on CT images. It is seen in 4%-9% of smokers and 2%-7% of nonsmokers. ILA has a tendency to progress with time and is associated with respiratory symptoms, decreased exercise capability, reduced pulmonary function, and increased mortality. ILAs can be classified into three subcategories: nonsubpleural, subpleural nonfibrotic, and subpleural fibrotic. In cases of ILA, clinically significant interstitial lung disease should be identified and requires clinically driven management by a pulmonologist. Risk factors for the progression of ILA include clinical elements (ie, inhalation exposures, medication use, radiation therapy, thoracic surgery, physiologic findings, and gas exchange findings) and radiologic elements (ie, basal and peripheral predominance and fibrotic findings). It is recommended that individuals with one or more clinical or radiologic risk factors for progression of ILA be actively monitored with pulmonary function testing and CT. To avoid overcalling ILA at CT, radiologists must recognize the imaging pitfalls, including centrilobular nodularity, dependent abnormality, suboptimal inspiration, osteophyte-related lesions, apical cap and pleuroparenchymal fibroelastosis-like lesions, aspiration, and infection. There is a close association between ILA and lung cancer, and many studies have reported an increased incidence of lung cancer, worse prognoses, and/or increased pulmonary complications in relation to cancer treatment in patients with ILA. ILA is considered to be an important comorbidity in patients with lung cancer. Accordingly, all radiologists involved with body CT must have sound knowledge of ILAs owing to the high prevalence and potential clinical significance of these anomalies. An overview of ILAs, including a literature review of the associations between ILAs and lung cancer, is presented. ©RSNA, 2022.

Traction Bronchiectasis/Bronchiolectasis on CT Scans in Relationship to Clinical Outcomes and Mortality: The COPDGene Study

Background The clinical impact of interstitial lung abnormalities (ILAs) on poor prognosis has been reported in many studies, but risk stratification in ILA will contribute to clinical practice. Purpose To investigate the association of traction bronchiectasis/bronchiolectasis index (TBI) with mortality and clinical outcomes in individuals with ILA by using the COPDGene cohort. Materials and Methods This study was a secondary analysis of prospectively collected data. Chest CT scans of participants with ILA for traction bronchiectasis/bronchiolectasis were evaluated and outcomes were compared with participants without ILA from the COPDGene study (January 2008 to June 2011). TBI was classified as follows: TBI-0, ILA without traction bronchiectasis/bronchiolectasis; TBI-1, ILA with bronchiolectasis but without bronchiectasis or architectural distortion; TBI-2, ILA with mild to moderate traction bronchiectasis; and TBI-3, ILA with severe traction bronchiectasis and/or honeycombing. Clinical outcomes and overall survival were compared among the TBI groups and the non-ILA group by using multivariable linear regression model and Cox proportional hazards model, respectively. Results Overall, 5295 participants (median age, 59 years; IQR, 52-66 years; 2779 men) were included, and 582 participants with ILA and 4713 participants without ILA were identified. TBI groups were associated with poorer clinical outcomes such as quality of life scores in the multivariable linear regression model (TBI-0: coefficient, 3.2 [95% CI: 0.6, 5.7; P = .01]; TBI-1: coefficient, 3.3 [95% CI: 1.1, 5.6; P = .003]; TBI-2: coefficient, 7.6 [95% CI: 4.0, 11; P < .001]; TBI-3: coefficient, 32 [95% CI: 17, 48; P < .001]). The multivariable Cox model demonstrated that ILA without traction bronchiectasis (TBI-0-1) and with traction bronchiectasis (TBI-2-3) were associated with shorter overall survival (TBI-0-1: hazard ratio [HR], 1.4 [95% CI: 1.0, 1.9; P = .049]; TBI-2-3: HR, 3.8 [95% CI: 2.6, 5.6; P < .001]). Conclusion Traction bronchiectasis/bronchiolectasis was associated with poorer clinical outcomes compared with the group without interstitial lung abnormalities; TBI-2 and 3 were associated with shorter survival. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Lee and Im in this issue.

The Proteomic Profile of Interstitial Lung Abnormalities

Rationale: Knowledge on biomarkers of interstitial lung disease is incomplete. Interstitial lung abnormalities (ILAs) are radiologic changes that may present in its early stages. Objectives: To uncover blood proteins associated with ILAs using large-scale proteomics methods. Methods: Data from two prospective cohort studies, the AGES-Reykjavik (Age, Gene/Environment Susceptibility-Reykjavik) study (N = 5,259) for biomarker discovery and the COPDGene (Genetic Epidemiology of COPD) study (N = 4,899) for replication, were used. Blood proteins were measured using DNA aptamers, targeting more than 4,700 protein analytes. The association of proteins with ILAs and ILA progression was assessed with regression modeling, as were associations with genetic risk factors. Adaptive Least Absolute Shrinkage and Selection Operator models were applied to bootstrap data samples to discover sets of proteins predictive of ILAs and their progression. Measurements and Main Results: Of 287 associations, SFTPB (surfactant protein B) (odds ratio [OR], 3.71 [95% confidence interval (CI), 3.20-4.30]; P = 4.28 × 10^-67), SCGB3A1 (Secretoglobin family 3A member 1) (OR, 2.43 [95% CI, 2.13-2.77]; P = 8.01 × 10^-40), and WFDC2 (WAP four-disulfide core domain protein 2) (OR, 2.42 [95% CI, 2.11-2.78]; P = 4.01 × 10^-36) were most significantly associated with ILA in AGES-Reykjavik and were replicated in COPDGene. In AGES-Reykjavik, concentrations of SFTPB were associated with the rs35705950 MUC5B (mucin 5B) promoter polymorphism, and SFTPB and WFDC2 had the strongest associations with ILA progression. Multivariate models of ILAs in AGES-Reykjavik, ILAs in COPDGene, and ILA progression in AGES-Reykjavik had validated areas under the receiver operating characteristic curve of 0.880, 0.826, and 0.824, respectively. Conclusions: Novel, replicated associations of ILA, its progression, and genetic risk factors with numerous blood proteins are demonstrated as well as machine-learning-based models with favorable predictive potential. Several proteins are revealed as potential markers of early fibrotic lung disease.

Associations of Monocyte Count and Other Immune Cell Types with Interstitial Lung Abnormalities

Rationale: Higher blood monocyte counts are associated with worse survival in adults with clinically diagnosed pulmonary fibrosis. Their association with the development and progression of interstitial lung abnormalities (ILA) in humans is unknown. Objectives: We evaluated the associations of blood monocyte count, and other immune cell types, with ILA, high-attenuation areas, and FVC in four independent cohorts. Methods: We included participants with measured monocyte counts and computed tomographic (CT) imaging enrolled in MESA (Multi-Ethnic Study of Atherosclerosis, n = 484), AGES-Reykjavik (Age/Gene Environment Susceptibility Study, n = 3,547), COPDGene (Genetic Epidemiology of COPD, n = 2,719), and the ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points, n = 646). Measurements and Main Results: After adjustment for covariates, a 1-SD increment in blood monocyte count was associated with ILA in MESA (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.0-1.8), AGES-Reykjavik (OR, 1.2; 95% CI, 1.1-1.3), COPDGene (OR, 1.3; 95% CI, 1.2-1.4), and ECLIPSE (OR, 1.2; 95% CI, 1.0-1.4). A higher monocyte count was associated with ILA progression over 5 years in AGES-Reykjavik (OR, 1.2; 95% CI, 1.0-1.3). Compared with participants without ILA, there was a higher percentage of activated monocytes among those with ILA in MESA. Higher monocyte count was associated with greater high-attenuation areas in MESA and lower FVC in MESA and COPDGene. Associations of other immune cell types were less consistent. Conclusions: Higher blood monocyte counts were associated with the presence and progression of interstitial lung abnormalities and lower FVC.

Vector-field dynamic x-ray (VF-DXR) using optical flow method in patients with chronic obstructive pulmonary disease

BACKGROUND

We assessed the difference in lung motion during inspiration/expiration between chronic obstructive pulmonary disease (COPD) patients and healthy volunteers using vector-field dynamic x-ray (VF-DXR) with optical flow method (OFM).

METHODS

We enrolled 36 COPD patients and 47 healthy volunteers, classified according to pulmonary function into: normal, COPD mild, and COPD severe. Contrast gradient was obtained from sequential dynamic x-ray (DXR) and converted to motion vector using OFM. VF-DXR images were created by projection of the vertical component of lung motion vectors onto DXR images. The maximum magnitude of lung motion vectors in tidal inspiration/expiration, forced inspiration/expiration were selected and defined as lung motion velocity (LMV). Correlations between LMV with demographics and pulmonary function and differences in LMV between COPD patients and healthy volunteers were investigated.

RESULTS

Negative correlations were confirmed between LMV and % forced expiratory volume in one second (%FEV1) in the tidal inspiration in the right lung (Spearman's rank correlation coefficient, rs = -0.47, p < 0.001) and the left lung (rs = -0.32, p = 0.033). A positive correlation between LMV and %FEV1 in the tidal expiration was observed only in the right lung (rs = 0.25, p = 0.024). LMVs among normal, COPD mild and COPD severe groups were different in the tidal respiration. COPD mild group showed a significantly larger magnitude of LMV compared with the normal group.

CONCLUSIONS

In the tidal inspiration, the lung parenchyma moved faster in COPD patients compared with healthy volunteers. VF-DXR was feasible for the assessment of lung parenchyma using LMV.

A Case-control Study of Major Genetic Predisposition Risk Alleles in Developing DDD in the Northeast US Population: Effects of Gene-gene Interactions

STUDY DESIGN

A case-control study of risk alleles for degenerative disc disease (DDD) using magnetic resonance (MR) imaging for phenotyping.

OBJECTIVE

We aim to provide the first statistically adequately powered study of the relationship between the presence of common risk alleles and occurrence of DDD in Eastern US population.

SUMMARY OF BACKGROUND DATA

Many genetic predisposing factors have been identified in elevating the risk of DDD, including common variants in VDR, COL1A1, AGC1, COL9A2/3 genes.

METHODS

We utilized the Mass General Brigham (MGB) Biobank in which subjects' Medical Record is linked with genotyped data from single-nucleotide polymorphism (SNP) arrays. Subjects with lumbosacral spine MR imaging studies were used to construct the Cases cohort; the Biobank's Controls cohort was used as the Control cohort. Odds ratios (OR) and False-discovery-rate (FDR) q values from multiple-hypotheses-testing corrections were used to assess the likelihood of DDD given occurrence of the listed DDD risk alleles.

RESULTS

Four-hundred-fourteen subjects (mean age = 64, range = 27 to 94) were Cases and 925 Controls (mean age = 46, range = 21-61). A systematic search has identified 25 SNPs in 18 genes in the SNP arrays. At univariate level, rs1544410 in VDR was significantly associated with DDD for male subjects (odds ratio [OR] = 0.594, P = 0.011). After adjustment for all significant variants and demographics, three predictor variables had a significant association with the outcome, age (OR = 1.130, q < 0.0001), rs143383 (OR = 1.951, q = 0.056), and rs3737821 (OR = 2.701, q = 0.069). A novel variant-to-variant correlation rs143383:rs763110 had a significant adjusted OR = 7.933, q = 0.070).

CONCLUSION

In this large-scale study of common variants' correlation with the presence of DDD in the Northeast United States, we have found a novel and significant variant-to-variant interaction to be associated with the risk of developing DDD, corroborating and necessitating the inclusion of gene-gene interactions in predictive risk model development for DDD.Level of Evidence: 4.

Evaluation of MR imaging findings differentiating parotid basal cell adenomas from other parotid tumors

PURPOSE

To evaluate the usefulness of magnetic resonance imaging (MRI) to differentiate basal cell adenomas (BCAs) from other parotid tumors.

METHOD

A total of 136 patients with histologically proven parotid gland tumors (13 BCAs, 66 pleomorphic adenomas [PAs], 30 Warthin tumors [WTs], and 27 parotid cancers [PCs]) who underwent a cervical MRI study between December 2011 and March 2019 were retrospectively enrolled. The MRI findings of the tumors were evaluated by two board-certified radiologists.

RESULTS

All 13 of the BCAs showed smooth margins, while 19 of the 27 PCs showed irregular margins (p < 0.0001). Eleven BCAs had some cystic components, and five were cyst-dominant. The BCAs had significantly more cystic components than the PAs (p = 0.0077). The mean apparent diffusion coefficient (ADC) value of the BCAs was 1.21 ± 0.20 × 10^-3 mm²/sec, which was equivalent to that of the PCs (1.12 ± 0.25 × 10^-3 mm²/sec, p = 0.76), significantly lower than that of the PAs (1.61 ± 0.32 × 10^-3 mm²/sec, p < 0.0001), and significantly higher than that of the WTs (0.81 ± 0.19 × 10^-3 mm²/sec, p = 0.0004). The plateau time-intensity curve (TIC) was the most common type for both BCAs and PCs, seen in 8 of 12 BCAs and 21 of 26 PCs, with no significant difference between these groups (p = 0.34).

CONCLUSIONS

BCA should be considered a possibility when a parotid lesion has smooth margins with an entire capsule and includes a cystic component, even if the TIC and diffusion-weighted MR images suggest a malignant pattern.

Model-based iterative reconstruction for 320-detector row CT angiography reduces radiation exposure in infants with complex congenital heart disease

PURPOSE

We investigated the impact of model-based iterative reconstruction (MBIR) on 320-detector row computed tomography angiography (CTA) in infants with complex congenital heart disease (CHD).

METHODS

Seventy infants with complex CHD who underwent 320-detector row CTA (40 boys and 30 girls; age range, 0-22 months; median age, 60 days) were retrospectively evaluated. First, the images were reconstructed by filtered back projection (FBP), hybrid iterative reconstruction (HIR), or MBIR in 20 cases, and variables were compared among the three iterative reconstruction methods (IR test). Second, the variables were compared between 25 cases scanned using HIR and 25 cases scanned using MBIR, with a 20 standard deviation noise level for both. Attenuation values and contrast-to-noise ratios (CNRs) of the great vessels and heart chambers were calculated. Total dose-length products were recorded for all patients (radiation dose: RD test).

RESULTS

In the IR test, the mean CNR values were 4.8±1.3 for FBP, 6.9±1.4 for HIR, and 8.2±1.7 for MBIR (P < 0.0001). The best subjective image qualities in the great vessels and heart chambers were obtained with MBIR. In RD testing, no significant differences between HIR and MBIR in image quality (CNR: HIR, 8.4±2.4; MBIR, 8.3±2.4) were observed. The effective dose was significantly lower for MBIR than for HIR (0.7±0.2 vs. 1.1±0.3 mSv; P < 0.001).

CONCLUSION

The MBIR algorithm significantly improved image quality and decreased radiation exposure in 320-row CTA of infants with complex CHD, providing an alternative to FBP or HIR that is both safer and produces better results.

Nivolumab with carboplatin, paclitaxel, and bevacizumab for first-line treatment of advanced nonsquamous non-small-cell lung cancer

BACKGROUND

This international, randomized, double-blind phase III study (ONO-4538-52/TASUKI-52) evaluated nivolumab with bevacizumab and cytotoxic chemotherapy as first-line treatment for nonsquamous non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Between June 2017 and July 2019, this study enrolled treatment-naïve patients with stage IIIB/IV or recurrent nonsquamous NSCLC without sensitizing EGFR, ALK, or ROS1 alterations. They were randomly assigned in a 1 : 1 ratio to receive nivolumab or placebo in combination with carboplatin, paclitaxel, and bevacizumab every 3 weeks for up to six cycles, followed by nivolumab/placebo with bevacizumab until progressive disease or unacceptable toxicity. The primary endpoint was progression-free survival (PFS) assessed by an independent radiology review committee (IRRC).

RESULTS

Overall, 550 patients from Japan, Korea, and Taiwan were randomized; of these patients, 273 and 275 received the nivolumab and placebo combinations, respectively. In the present preplanned interim analysis with a median follow up of 13.7 months, the IRRC-assessed median PFS was significantly longer in the nivolumab arm than in the placebo arm (12.1 versus 8.1 months; hazard ratio 0.56; 96.4% confidence interval 0.43-0.71; P < 0.0001). The PFS benefit was observed across all patients with any programmed death-ligand 1 (PD-L1) expression levels including PD-L1-negative patients. The IRRC-assessed objective response rates were 61.5% and 50.5% in the nivolumab and placebo arms, respectively. The incidence of treatment-related adverse events of grade 3 or 4 was comparable between the two arms; treatment-related adverse events leading to death were observed in five and four patients in the nivolumab and placebo arms, respectively.

CONCLUSION

The TASUKI-52 regimen should be considered a viable new treatment strategy for treatment-naïve patients with advanced nonsquamous NSCLC.

Progression of traction bronchiectasis/bronchiolectasis in interstitial lung abnormalities is associated with increased all-cause mortality: Age Gene/Environment Susceptibility-Reykjavik Study

PURPOSE

The aim of this study is to assess the role of traction bronchiectasis/bronchiolectasis and its progression as a predictor for early fibrosis in interstitial lung abnormalities (ILA).

METHODS

Three hundred twenty-seven ILA participants out of 5764 in the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study who had undergone chest CT twice with an interval of approximately five-years were enrolled in this study. Traction bronchiectasis/bronchiolectasis index (TBI) was classified on a four-point scale: 0, ILA without traction bronchiectasis/bronchiolectasis; 1, ILA with bronchiolectasis but without bronchiectasis or architectural distortion; 2, ILA with mild to moderate traction bronchiectasis; 3, ILA and severe traction bronchiectasis and/or honeycombing. Traction bronchiectasis (TB) progression was classified on a five-point scale: 1, Improved; 2, Probably improved; 3, No change; 4, Probably progressed; 5, Progressed. Overall survival (OS) among participants with different TB Progression Score and between the TB progression group and No TB progression group was also investigated. Hazard radio (HR) was estimated with Cox proportional hazards model.

RESULTS

The higher the TBI at baseline, the higher TB Progression Score (P < 0.001). All five participants with TBI = 3 at baseline progressed; 46 (90 %) of 51 participants with TBI = 2 progressed. TB progression was also associated with shorter OS with statistically significant difference (adjusted HR = 1.68, P < 0.001).

CONCLUSION

TB progression was visualized on chest CT frequently and clearly. It has the potential to be the predictor for poorer prognosis of ILA.

Right Ventricular Extracellular Volume with Dual-Layer Spectral Detector CT: Value in Chronic Thromboembolic Pulmonary Hypertension

Background Right ventricular (RV) extracellular volumes (ECVs), as a surrogate for histologic fibrosis, have not been sufficiently investigated. Purpose To evaluate and compare RV and left ventricular (LV) ECVs obtained with dual-layer spectral detector CT (DLCT) in chronic thromboembolic pulmonary hypertension (CTEPH) and investigate the clinical importance of RV ECV. Materials and Methods Retrospective analysis was performed on data from 31 patients with CTEPH (17 were not treated with pulmonary endarterectomy [PEA] or balloon pulmonary angioplasty [BPA] and 14 were) and eight control subjects who underwent myocardial delayed enhancement (MDE) DLCT from January 2019 to June 2020. The ECVs in the RV and LV walls were calculated by using iodine density as derived from spectral data pertaining to MDE. Statistical analyses were performed with one-way repeated analysis of variance with the Tukey post hoc test or the Kruskal-Wallis test with the Steel-Dwass test and linear regression analysis. Results The PEA- and BPA-naive group showed significantly higher ECVs than the PEA- or BPA-treated group and control group in the septum (28.2% ± 2.9 vs 24.3% ± 3.6, P = .005), anterior right ventricular insertion point (RVIP) (32.9% ± 4.6 vs 25.3% ± 3.6, P < .001), posterior RVIP (35.2% ± 5.2 vs 27.3% ± 4.2, P < .001), mean RVIP (34.0% ± 4.2 vs 26.3% ± 3.4, P < .001), RV free wall (29.5% ± 3.3 vs 25.9% ± 4.1, P = .036), and mean RV wall (29.1% ± 3.0 vs 26.1% ± 3.1, P = .029). There were no significant differences between the PEA- or BPA-treated group and control subjects in these segments (septum, P = .93; anterior RVIP, P = .38; posterior RVIP, P = .52; mean RVIP, P = .36; RV free wall, P = .97; and mean RV, P = .33). There were significant correlations between ECV and mean pulmonary artery pressure (PAP) or brain natriuretic peptide (BNP) in the mean RVIP (mean PAP: R = 0.66, P < .001; BNP: R = 0.44, P = .014) and the mean RV (mean PAP: R = 0.49, P = .005; BNP: R = 0.44, P = .013). Conclusion Right ventricular and right ventricular insertion point extracellular volumes could be noninvasive surrogate markers of disease severity and reverse tissue remodeling in chronic thromboembolic pulmonary hypertension. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Sandfort and Bluemke in this issue.

Interstitial lung abnormalities in patients with stage I non-small cell lung cancer are associated with shorter overall survival: the Boston lung cancer study

BACKGROUND

Interstitial lung abnormalities (ILA) can be detected on computed tomography (CT) in lung cancer patients and have an association with mortality in advanced non-small cell lung cancer (NSCLC) patients. The aim of this study is to demonstrate the significance of ILA for mortality in patients with stage I NSCLC using Boston Lung Cancer Study cohort.

METHODS

Two hundred and thirty-one patients with stage I NSCLC from 2000 to 2011 were investigated in this retrospective study (median age, 69 years; 93 males, 138 females). ILA was scored on baseline CT scans prior to treatment using a 3-point scale (0 = no evidence of ILA, 1 = equivocal for ILA, 2 = ILA) by a sequential reading method. ILA score 2 was considered the presence of ILA. The difference of overall survival (OS) for patients with different ILA scores were tested via log-rank test and multivariate Cox proportional hazards models were used to estimate hazard ratios (HRs) including ILA score, age, sex, smoking status, and treatment as the confounding variables.

RESULTS

ILA was present in 22 out of 231 patients (9.5%) with stage I NSCLC. The presence of ILA was associated with shorter OS (patients with ILA score 2, median 3.85 years [95% confidence interval (CI): 3.36 - not reached (NR)]; patients with ILA score 0 or 1, median 10.16 years [95%CI: 8.65 - NR]; P <  0.0001). In a Cox proportional hazards model, the presence of ILA remained significant for increased risk for death (HR = 2.88, P = 0.005) after adjusting for age, sex, smoking and treatment.

CONCLUSIONS

ILA was detected on CT in 9.5% of patients with stage I NSCLC. The presence of ILA was significantly associated with a shorter OS and could be an imaging marker of shorter survival in stage I NSCLC.

Dynamic Chest X-Ray Using a Flat-Panel Detector System: Technique and Applications

Dynamic X-ray (DXR) is a functional imaging technique that uses sequential images obtained by a flat-panel detector (FPD). This article aims to describe the mechanism of DXR and the analysis methods used as well as review the clinical evidence for its use. DXR analyzes dynamic changes on the basis of X-ray translucency and can be used for analysis of diaphragmatic kinetics, ventilation, and lung perfusion. It offers many advantages such as a high temporal resolution and flexibility in body positioning. Many clinical studies have reported the feasibility of DXR and its characteristic findings in pulmonary diseases. DXR may serve as an alternative to pulmonary function tests in patients requiring contact inhibition, including patients with suspected or confirmed coronavirus disease 2019 or other infectious diseases. Thus, DXR has a great potential to play an important role in the clinical setting. Further investigations are needed to utilize DXR more effectively and to establish it as a valuable diagnostic tool.

Simple quantitative chest CT for pulmonary edema

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Quantitative CT is a highly accurate but underutilized method for identifying pulmonary edema on CT.

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There is a moderatelystrong correlation between CT HUs and CXR pulmonary edema grade in every lobe with correlation coefficients ranging from 0.585−0.685.

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CT Hounsfield unit measurement yields excellent accuracy in differentiating no edema from mild to severe edema, with AUCs up to 0.995 in the LUL.

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Qualitative CT with a % versus 84 % and specificity 95 % versus 78 Qualitative CT with a HU cut-off of -825 in the LUL is more sensitive (100% vs 84%) and specific (95% vs 78%) than qualitative CT.

Purpose

To determine the accuracy of quantitative CT to diagnose pulmonary edema compared to qualitative CT and CXR and to determine a threshold Hounsfield unit (HU) measurement for pulmonary edema on CT examinations.

Method

Electronic medical records were searched for patients with a billing diagnosis of heart failure and a Chest CT and CXR performed within three hours between 1/1/2016 to 10/1/2016, yielding 100 patients. CXR and CT examinations were scored for the presence and severity of edema, using a 0–5 scale, and CT HU measurements were obtained in each lobe. Polyserial correlation coefficients evaluated the association between CT HUs and CXR scores, and receiver operating characteristic (ROC) curve analysis determined a cutoff CT HU value for identification of pulmonary edema.

Results

Correlation between CT HU and CXR score was moderately strong (r = 0.585−0.685) with CT HU measurements demonstrating good to excellent accuracy in differentiating between no edema (grade 0) and mild to severe edema (grades 1–5) in every lobe, with AUCs ranging between 0.869 and 0.995. The left upper lobe demonstrated the highest accuracy, using a cutoff value of -825 HU (AUC of 0.995, sensitivity = 100 % and specificity = 95.1 %). Additionally, qualitative CT evaluation was less sensitive (84 %) than portable CXR in identifying pulmonary edema. However, quantitative CT evaluation was as sensitive as portable CXR (100 %) and highly specific (95 %).

Conclusions

Quantitative CT enables the identification of pulmonary edema with high accuracy and demonstrates a greater sensitivity than qualitative CT in assessment of pulmonary edema.

Projected lung areas using dynamic X-ray (DXR)

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The right projected lung area (PLA) was significantly larger than left one.

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PLA had correlation with height, weight, BMI, vital capacity (VC), and forced expiratory volume in one second (FEV₁).

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Multivariate analysis showed that body mass index (BMI), sex and VC were considered independent correlation factors, respectively.

Background

Dynamic X-ray (DXR) provides images of multiple phases of breath with less radiation exposure than CT. The exact images at end-inspiratory or end-expiratory phases can be chosen accurately.

Purpose

To investigate the correlation of the projected lung area (PLA) by dynamic chest X-ray with pulmonary functions.

Material and Methods

One hundred sixty-two healthy volunteers who received medical check-ups for health screening were included in this study. All subjects underwent DXR in both posteroanterior (PA) and lateral views and pulmonary function tests on the same day. All the volunteers took several tidal breaths before one forced breath as instructed. The outlines of lungs were contoured manually on the workstation with reference to the motion of diaphragm and the graph of pixel values. The PLAs were calculated automatically, and correlations with pulmonary functions and demographic data were analyzed statistically.

Results

The PLAs have correlation with physical characteristics, including height, weight and BMI, and pulmonary functions such as vital capacity (VC) and forced expiratory volume in one second (FEV₁). VC and FEV₁ revealed moderate correlation with the PLAs of PA view in forced inspiratory phase (VC: right, r = 0.65; left, r = 0.69. FEV1: right, r = 0.54; left, r = 0.59). Multivariate analysis showed that body mass index (BMI), sex and VC were considered independent correlation factors, respectively.

Conclusion

PLA showed statistically significant correlation with pulmonary functions. Our results indicate DXR has a possibility to serve as an alternate method for pulmonary function tests in subjects requiring contact inhibition including patients with suspected or confirmed covid-19.

Balloon pulmonary angioplasty improves right atrial reservoir and conduit functions in chronic thromboembolic pulmonary hypertension

AIMS

Right atrial (RA) function largely contributes to the maintenance of right ventricular (RV) function. This study investigated the effect of balloon pulmonary angioplasty (BPA) on RA functions in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) using cardiac magnetic resonance imaging (CMRI).

METHODS AND RESULTS

CMRI and RV catheterization were performed before BPA sessions and at the follow-up periods in 29 CTEPH patients. Reservoir [RA longitudinal strain (RA-LS)], passive conduit [RA early LS rate (LSR)], and active (RA late LSR) phases were assessed by using cine CMRI and a feature-tracking algorithm. The relationships between the changes in RA functions and in brain natriuretic peptide (BNP) were evaluated in both the dilated and non-dilated RA groups. RA-LS (32.4% vs. 42.7%), RA LSR (6.3% vs. 8.3%), and RA early LSR (-2.3% vs. -4.3%) were improved after BPA, whereas no significant change was seen in RA late LSR. The changes in RA peak LS and in RA early LSR were significantly correlated with the changes in BNP (ΔRA-LS: r = -0.63, ΔRA-early LSR: r = 0.65) and pulmonary vascular resistance (PVR) (ΔRA-LS: r = -0.69, ΔRA-early LSR: r = 0.66) in the nondilated RA group.

CONCLUSION

The RA reservoir and passive conduit functions were impaired in inoperable CTEPH, whereas RA active function was preserved. BPA markedly reversed these impaired functions. The improvements in RA reservoir and conduit functions were significantly correlated with the changes in BNP levels and PVR in CTEPH patients with normal RA sizes.

Amide proton transfer (APT) imaging of parotid tumors: Differentiation of malignant and benign tumors

PURPOSE

To assess the usefulness of amide proton transfer (APT) imaging in differentiating parotid tumors.

MATERIAL AND METHODS

We retrospectively analyzed 43 histopathologically proven parotid solid tumors with diameters ≥2 cm. Twenty-one tumors were benign and 12 tumors were malignant. Two-dimensional APT imaging was performed using a saturation pulse with a duration of 2 s and a saturation power level of 2 μT. For acquiring Z-spectra, the imaging was repeated at 25 saturation frequency offsets from ω = -6 to +6 ppm with a step of 0.5 ppm as well as one scan acquired far off-resonance (-1560 ppm) for signal normalization. For the APT imaging, the asymmetry analysis at 3.5 ppm downfield from the water signal was calculated. The mean APT signal intensity (SI) was compared between the benign and malignant tumors.

RESULTS

The mean APT SI was 2.23 ± 0.80 % in the benign tumors and significantly higher at 2.99 ± 0.99 % in the malignant tumors (P = 0.01). A receiver operating curve analysis revealed that the optimal APT SI threshold was 2.40 for distinguishing malignant tumors from benign tumors with an area under the curve of 0.74. The sensitivity, specificity, and accuracy were 83.3%, 61.3%, and 67.4%, respectively.

CONCLUSION

The mean APT SI of the malignant parotid tumors was significantly higher than that of the benign parotid tumors.

Traction Bronchiectasis/Bronchiolectasis is Associated with Interstitial Lung Abnormality Mortality

PURPOSE

To investigate if the presence and severity of traction bronchiectasis/bronchiolectasis are associated with poorer survival in subjects with ILA.

METHOD

The study included 3,594 subjects (378 subjects with ILA and 3,216 subjects without ILA) in AGES-Reykjavik Study. Chest CT scans of 378 subjects with ILA were evaluated for traction bronchiectasis/bronchiolectasis, defined as dilatation of bronchi/bronchioles within areas demonstrating ILA. Traction bronchiectasis/bronchiolectasis Index (TBI) was assigned as: TBI = 0, ILA without traction bronchiectasis/bronchiolectasis: TBI = 1, ILA with bronchiolectasis but without bronchiectasis or architectural distortion: TBI = 2, ILA with mild to moderate traction bronchiectasis: TBI = 3, ILA and severe traction bronchiectasis and/or honeycombing. Overall survival (OS) was compared among the subjects in different TBI groups and those without ILA.

RESULTS

The median OS was 12.93 years (95%CI; 12.67 - 13.43) in the subjects without ILA; 11.95 years (10.03 - not reached) in TBI-0 group; 8.52 years (7.57 - 9.30) in TBI-1 group; 7.63 years (6.09 - 9.10) in TBI-2 group; 5.40 years (1.85 - 5.98) in TBI-3 group. The multivariable Cox models demonstrated significantly shorter OS of TBI-1, TBI-2, and TBI-3 groups compared to subjects without ILA (P < 0.0001), whereas TBI-0 group had no significant OS difference compared to subjects without ILA, after adjusting for age, sex, and smoking status.

CONCLUSIONS

The presence and severity of traction bronchiectasis/bronchiolectasis are associated with shorter survival. The traction bronchiectasis/bronchiolectasis is an important contributor to increased mortality among subjects with ILA.

Imaging Patterns Are Associated with Interstitial Lung Abnormality Progression and Mortality

Rationale: Interstitial lung abnormalities (ILA) are radiologic abnormalities on chest computed tomography scans that have been associated with an early or mild form of pulmonary fibrosis. Although ILA have been associated with radiologic progression, it is not known if specific imaging patterns are associated with progression or risk of mortality. Objectives: To determine the role of imaging patterns on the risk of death and ILA progression. Methods: ILA (and imaging pattern) were assessed in 5,320 participants from the AGES-Reykjavik Study, and ILA progression was assessed in 3,167 participants. Multivariable logistic regression was used to assess factors associated with ILA progression, and Cox proportional hazards models were used to assess time to mortality. Measurements and Main Results: Over 5 years, 327 (10%) had ILA on at least one computed tomography, and 1,435 (45%) did not have ILA on either computed tomography. Of those with ILA, 238 (73%) had imaging progression, whereas 89 (27%) had stable to improved imaging; increasing age and copies of MUC5B genotype were associated with imaging progression. The definite fibrosis pattern was associated with the highest risk of progression (odds ratio, 8.4; 95% confidence interval, 2.7-25; P = 0.0003). Specific imaging patterns were also associated with an increased risk of death. After adjustment, both a probable usual interstitial pneumonia and usual interstitial pneumonia pattern were associated with an increased risk of death when compared with those indeterminate for usual interstitial pneumonia (hazard ratio, 1.7; 95% confidence interval, 1.2-2.4; P = 0.001; hazard ratio, 3.9; 95% confidence interval, 2.3-6.8;P < 0.0001), respectively. Conclusions: In those with ILA, imaging patterns can be used to help predict who is at the greatest risk of progression and early death.

Real-world prevalence of programmed death ligand 1 expression in locally advanced or metastatic non-small-cell lung cancer: The global, multicenter EXPRESS study

OBJECTIVES

Tumor programmed death ligand 1 (PD-L1) expression is associated with improved clinical benefit from immunotherapies targeting the PD-1 pathway. We conducted a global, multicenter, retrospective observational study to determine real-world prevalence of tumor PD-L1 expression in patients with NSCLC.

MATERIALS AND METHODS

Patients ≥18 years with histologically confirmed stage IIIB/IV NSCLC and a tumor tissue block (≤5 years old) obtained before treatment were identified in 45 centers across 18 countries. Tumor samples from eligible patients were selected consecutively, when possible. PD-L1 expression was evaluated at each center using the PD-L1 IHC 22C3 pharmDx kit (Agilent, Santa Clara, CA, USA).

RESULTS

Of 2617 patients who met inclusion criteria, 2368 (90%) had PD-L1 data; 530 (22%) patients had PD-L1 TPS ≥ 50%, 1232 (52%) had PD-L1 TPS ≥ 1%, and 1136 (48%) had PD-L1 TPS < 1%. The most common reason for not having PD-L1 data (n = 249) was insufficient tumor cells (<100) on the slide (n = 170 [6%]). Percentages of patients with PD-L1 TPS ≥ 50% and TPS ≥ 1%, respectively were: 22%/52% in Europe; 22%/53% in Asia Pacific; 21%/47% in the Americas, and 24%/55% in other countries. Prevalence of EGFR mutations (19%) and ALK alterations (3%) was consistent with prior reports from metastatic NSCLC studies. Among 1064 patients negative for both EGFR mutation and ALK alteration, the percentage with PD-L1 TPS ≥ 50% and TPS ≥ 1%, respectively, were 27% and 53%.

CONCLUSIONS

This is the largest real-world study in advanced NSCLC to date evaluating PD-L1 tumor expression using the 22C3 pharmDx kit. Testing failure rate was low with local evaluation of PD-L1 TPS across a large number of centers. Prevalence of PD-L1 TPS ≥ 50% and TPS ≥ 1% among patients with stage IIIB/IV NSCLC was similar across geographic regions and broadly consistent with central testing results from clinical trial screening populations.

Interstitial lung abnormality in stage IV non-small cell lung cancer: A validation study for the association with poor clinical outcome

Purpose

The presence of interstitial lung abnormality (ILA) at diagnosis of stage IV non-small cell lung cancer (NSCLC) patients has previously shown to be associated with shorter overall survival (OS). The present study aimed to validate the association between ILA and shorter OS in a larger cohort of treatment-naïve stage IV NSCLC patients.

Materials and methods

This study includes 484 patients (205 men and 279 women) with a pathological diagnosis of stage IV NSCLC with pretreatment baseline CT available for review. ILA was visually scored on the baseline chest CT with a 3-point scale (0=no ILA, 1=indeterminate for ILA, 2 = ILA) as published previously. Clinical characteristics and overall survival (OS) were compared in patients with ILA score 2 vs. those with ILA score 0 or 1.

Results

ILA was present (score 2) on baseline CT in 19 of 484 patients (3.9%, 95%CI2.4-6.1%). Patients with ILA were significantly older (p = 0.0008) and more commonly male (p = 0.03) compared to those with ILA score 0 or 1. Patients with ILA score 2 showed significantly shorter OS compared to those with ILA score 0 or 1 (median OS 9.95 months vs. 16.95 months; p = 0.0002). In multivariate analyses, baseline ILA score 2 remained significant as a marker for shorter OS (HR = 2.09, p = 0.004) after adjustments for age (HR = 1.48; p = 0.001), gender (HR = 1.22, p = 0.06), and smoking (HR = 0.79; p = 0.051).

Conclusions

ILA on baseline CT at diagnosis of stage IV NSCLC patients was associated with shorter OS (HR = 2.09, p = 0.004), validating ILA as an independent marker for poor clinical outcome.

Highly expressed EZH2 in combination with BAP1 and MTAP loss, as detected by immunohistochemistry, is useful for differentiating malignant pleural mesothelioma from reactive mesothelial hyperplasia

OBJECTIVE

Malignant pleural mesothelioma (MPM) is an aggressive neoplasm with poor prognosis. Loss of BRCA-associated protein 1 (BAP1) protein expression as detected by immunohistochemistry (IHC) and homozygous deletion (HD) of the 9p21 locus as detected by fluorescence in situ hybridization (FISH) permits differentiation of MPM from reactive mesothelial hyperplasia (RMH). We have previously reported that detecting the loss of methylthioadenosine phosphorylase (MTAP) using IHC is a surrogate assay for 9p21 FISH. Furthermore, enhancer of zeste homolog 2 (EZH2), which encodes a component of polycomb repressor complex 2 (PRC-2), has been overexpressed in various tumors as well as MPM. In the current study, we investigated whether EZH2 IHC assay, alone or in combination with BAP1 and MTAP IHC, is useful for distinguishing MPM from RMH.

MATERIALS AND METHODS

We examined IHC expression of EZH2, BAP1, and MTAP, and 9p21 FISH in MPM (n = 38) and RMH (n = 29) and analyzed the sensitivity and specificity of each detection assay for distinguishing MPM from RMH.

RESULTS AND CONCLUSION

EZH2, BAP1, and MTAP IHC, and 9p21 FISH were characterized by a 100% specificity each and 44.7%, 52.6%, 47.4%, and 65.8% sensitivities, respectively. A combination of EZH2 and BAP1 IHC, and 9p21 FISH showed the greatest sensitivity (89.5%). Using IHC alone (EZH2, BAP1, and MTAP IHC) also yielded a good sensitivity of 86.9%; this level is high enough for routine diagnostics. There were no statistically significant associations between expression of EZH2 and that of other markers (BAP1 and MTAP IHC) or 9p21 HD. However, a high expression level of EZH2 was significantly associated with short survival (P = 0.025). In conclusion, adding a high expression level of EZH2 to a combination of BAP1 and MTAP loss, all detected by IHC, demonstrated useful for discriminating MPM from RMH.

Decreased and slower diaphragmatic motion during forced breathing in severe COPD patients: Time-resolved quantitative analysis using dynamic chest radiography with a flat panel detector system

OBJECTIVE

To assess the diaphragmatic motion in chronic obstructive pulmonary disease (COPD) patients during forced breathing by time-resolved quantitative analysis using dynamic chest radiography and to demonstrate the characteristics and the difference from that in normal subjects.

MATERIALS AND METHODS

Thirty-one COPD patients and a matched control of 31 normal subjects on age, sex, height, and weight, who underwent chest radiographs during forced breathing using dynamic chest radiography, were included in this study. COPD patients were classified based on the criteria of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) (GOLD 1, n = 3; GOLD 2, n = 12; GOLD 3, n = 13; GOLD 4, n = 3). We measured excursions and peak motion speeds of the diaphragms for each participant. We compared the results among GOLD 1/2, GOLD 3/4 groups and normal subjects and investigated associations between the data, and participants' demographics, or pulmonary function.

RESULTS

The excursions of bilateral diaphragms were significantly decreased in the GOLD 3/4 group relative to normal subjects (right, 39.8 ± 15.3 mm vs. 52.7 ± 15.1 mm, P = 0.030; left, 43.7 ± 14.0 mm vs. 56.9 ± 15.5 mm, P = 0.017; mean ± standard deviation) and the GOLD 1/2 group (right, 39.8 ± 15.3 mm vs. 54.4 ± 16.7 mm, P = 0.036; left, 43.7 ± 14.0 mm vs. 60.5 ± 13.9 mm, P = 0.008). The peak motion speeds of the left diaphragm in the inspiratory phase were slower in the GOLD 1/2 group than in normal subjects (24.5 ± 8.0 mm/s vs. 33.6 ± 14.0 mm/s, P =  0.038), and in the GOLD 3/4 group than in normal subjects (25.6 ± 6.8 mm/s vs. 33.6 ± 14.0 mm/s, P =  0.067). The excursions of the diaphragms showed correlation with VC, %VC, and FEV₁, while the peak motion speeds showed no significant correlation with pulmonary function tests.

CONCLUSIONS

Time-resolved quantitative analysis of diaphragms with dynamic chest radiography indicated differences in diaphragmatic motion between COPD groups and normal subjects during forced breathing. The excursions of the diaphragms during forced breathing were significantly lower in the GOLD 3/4 group than those in the GOLD 1/2 group and normal subjects.

Amide proton transfer imaging to predict tumor response to neoadjuvant chemotherapy in locally advanced rectal cancer

BACKGROUND AND AIM

The amount of proteins and peptides can be estimated with amide proton transfer (APT) imaging. Previous studies demonstrated the usefulness of APT imaging to predict tumor malignancy. We determined whether APT imaging can predict the tumor response to neoadjuvant chemotherapy (NAC) in patients with locally advanced rectal cancer (LARC).

METHODS

Seventeen patients with LARC who underwent a pretherapeutic magnetic resonance examination including APT imaging and NAC (at least two courses) were enrolled. The APT-weighted imaging (WI) signal intensity (SI) (%) was defined as magnetization transfer ratio asymmetry (MTR_asym ) at the offset of 3.5 ppm. Each tumor was histologically evaluated for the degree of degeneration and necrosis and then classified as one of five histological Grades (0, none; 1a, less than 1/3; 1b, 1/3 to 2/3; 2, more than 2/3; 3, all). We compared the mean APTWI SIs of the tumors between the Grade 0/1a/1b (low-response group) and Grade 2/3 (high-response group) by Student's t-test. We used receiver operating characteristics curves to determine the diagnostic performance of the APTWI SI for predicting the tumor response.

RESULTS

The mean APTWI SI of the low-response group (n = 12; 3.05 ± 1.61%) was significantly higher than that of the high-response group (n = 5; 1.14 ± 1.13%) (P = 0.029). The area under the curve for predicting the tumor response using the APTWI SI was 0.87. When ≥2.75% was used as an indicator of low-response status, 75% sensitivity and 100% specificity of the APTWI SI were obtained.

CONCLUSION

Pretherapeutic APT imaging can predict the tumor response to NAC in patients with LARC.

Impact of body mass index on CT attenuation of adrenal adenoma

OBJECTIVE

To investigate whether lipid metabolism-related factors regulate unenhanced CT attenuation in adrenal adenoma (AA).

MATERIALS AND METHODS

Thirty-six patients with surgically proven AAs were enrolled in this study. The patients' underlying diseases were the following: primary aldosteronism (n = 24), Cushing's syndrome (n = 8), subclinical Cushing's syndrome (n = 3) and non-functioning AA (n = 1). Unenhanced CT attenuation of AAs and liver was measured. Pathologically, clear cell ratio (CCR) constituting each AA was qualitatively assessed. Clinical data including tumor diameter, body mass index (BMI), hemoglobin A1c, triglyceride, total cholesterol, blood cortisol and plasma aldosterone levels were also obtained. Simple and multiple linear regression analyses were performed to evaluate the radiological and clinicopathological factors associated with CT attenuation of AAs for all patients and separately for 25 patients with primary aldosteronism or non-functioning AA.

RESULTS

For all patients, there was a significant correlation between CT attenuation and each of CCR, BMI and blood cortisol levels (p < 0.05). For patients with primary aldosteronism or non-functioning AA, there was also a significant correlation between CT attenuation and CCR or BMI (p < 0.05).

CONCLUSION

In addition to pathological factors, lipid-metabolism-related factors including BMI and blood cortisol levels can affect unenhanced CT attenuation of AA.