Unravelling the health and economic burden of interstitial lung diseases in adults in Australia.

BACKGROUND: Interstitial lung diseases (ILD) are a heterogenous group of over 200 disorders affecting the pulmonary interstitium. Although there have been advances in knowledge on ILDs in Australia, the characterisation of the health and economic burden of disease remained largely undetermined until recently. OBJECTIVE: The main objective of this review is to provide a synopsis of health and economic burden of ILDs in Australia, based on recently completed research. DISCUSSION: Recent research has demonstrated that idiopathic pulmonary fibrosis (IPF) is the most frequent ILD in Australia. Incidence and prevalence of IPF have demonstrated an increasing trend over the past decades. Mortality has also increased over the past decades, but has shown a slight decreasing trend recently, since the introduction of antifibrotic medication. Health-related quality of life is poor in patients with IPF, and care is estimated to cost approximately AU$299 million per year in Australia. Early diagnosis and referral to tertiary care is crucial for favourable outcomes, and general practitioners are considerably important to this as the first interface to identify patients at risk and detect early symptoms of ILDs.

Risk assessment in interstitial lung disease: the incremental prognostic value of cardiopulmonary ultrasound.

BACKGROUND: The mortality risk of chronic interstitial lung disease (ILD) is currently assessed using the ILD-GAP score. The present study evaluates whether the addition of cardiopulmonary ultrasound parameters to the ILD-GAP score can further improve the predictive value of ILD-GAP. METHODS: Medical records from 91 patients with ILD hospitalized from June 2015 to March 2016 were retrospectively examined. The Lung ultrasound (LUS) score, right ventricular (RV) function, and mechanics were obtained from the cardiopulmonary ultrasound. The ILD-GAP score was calculated from demographic characteristics and pulmonary function parameters. Patients were followed up with until May 2020. The primary endpoint was all-cause death. RESULTS: After exclusions, 74 patients with ILD were included in the analysis. During the follow-up period, 36 patients with ILD survived (ILDs), and 38 patients died (ILDd). Compared to ILDs, the ILDd cases exhibited a higher number of B-lines, LUS score, and RV end-diastolic base dimension (RVD), but lower RV function. In multivariate analysis, the ILD-GAP score (hazard ratio, 2.88; 95% CI 1.38-5.99, P = 0.005), LUS score (hazard ratio 1.13; 95% CI 1.04-1.24, P = 0.006), and RVD (hazard ratio 1.09, 95% CI 1.03-1.16, P = 0.004) were significantly related to the risk of death. Adding the LUS score and RVD to the ILD-GAP score significantly improved the predictive value compared to the ILD-GAP score alone (C statistics 0.90 vs 0.76, P = 0.018). CONCLUSION: We investigated the utility of a new prognostic model for ILD that includes both cardiopulmonary ultrasound parameters (LUS score and RVD) and the ILD-GAP score. This model better reflects the severity of pulmonary fibrosis and cardiac involvement, and has incremental predictive value over the ILD-GAP score alone.

"Current place of impulse oscillometry in the assessment of pulmonary diseases."

In 1956, a diagnostic tool using the forced oscillation technique (FOT) was developed to examine respiratory functions. A modification of this method is impulse oscillometry (IOS). In the latter, a loudspeaker delivers to the respiratory system a regular, square pressure wave at a constant frequency from which all other individual frequencies are derived using spectral analysis. The usefulness of IOS has been examined in relation to COPD, asthma, interstitial lung diseases, obstructive sleep apnea, and other conditions. The greatest advantage, most notable in children, is the ability to monitor the course of a disease and to assess the response to therapy in a simple way, i.e., minimal requirements for the cooperation of the patient, rapid and reproducible measurements. The IOS shows similar or even higher sensitivity than spirometry in detecting small airways dysfunction (SAD). The most well-known result observed in peripheral airways disease (PAD) is the frequency dependence of resistance. Importantly, the abnormal resistance at a specific frequency may occur with normal spirometry in those with early PAD. Moreover, IOS is particularly useful if the patient cannot perform effort dependent exhalation. Despite its advantages, the technique is still poorly found in official worldwide recommendations. Nonetheless, considering the promising results of many studies, an increase in interest in IOS is expected, and it could soon be on par with standard pulmonary function tests. The aim of this work is to present the basics, current views, and various aspects of IOS. To carry out our analysis, we searched for relevant publications on PubMed, Web of Science. Original and review articles were selected and discussed.

Healthcare Resources Utilization and Costs of Patients with Non-IPF Progressive Fibrosing Interstitial Lung Disease Based on Insurance Claims in the USA.

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is the classic progressive fibrosing interstitial lung disease (ILD), but some patients with ILDs other than IPF also develop a progressive fibrosing phenotype (PF-ILD). Information on use and cost of healthcare resources in patients with PF-ILD is limited. METHODS: We used USA-based medical insurance claims (2014-2016) to assess use and cost of healthcare resources in PF-ILD. Patients with at least two ILD claims and at least one pulmonologist visit were considered to have ILD. Pulmonologist visit frequency was used as a proxy to identify PF-ILD (at least four visits in 2016, or at least three more visits in 2016 vs. 2014). RESULTS: Of 2517 patients with non-IPF ILD, 15% (n = 373) had PF-ILD. Mean annual medical costs associated with ILD claims were $35,364 in patients with non-IPF PF-ILD versus $20,211 in the non-IPF ILD population. In 2016, patients with non-IPF PF-ILD made more hospital ILD claims than patients with non-IPF ILD (10.5 vs. 4.7). CONCLUSIONS: These findings suggest higher disease severity and overall healthcare use for patients with a non-IPF ILD manifesting a progressive fibrosing phenotype (non-IPF PF-ILD).

Interstitial lung disease (ILD) is a group of similar lung conditions with lung fibrosis, scarring, or inflammation of the lung tissue. Some patients with ILD also have worsening lung fibrosis, referred to as "progressive fibrosis" (PF-ILD). The most common type of PF-ILD is idiopathic pulmonary fibrosis (IPF), which has no known cause. Although much is known about IPF, there is limited information available on how often patients with ILDs other than IPF (non-IPF ILD) use healthcare, or the costs associated with the disease. This study used US medical insurance claims to gain further insights. The study examined data from over 2500 patients with non-IPF ILD, of which 15% had PF-ILD. Patients defined as having PF-ILD had higher yearly medical costs and used healthcare services more often than other patients with ILD. This study highlights the economic burden of non-IPF ILD with progressive fibrosis (non-IPF PF-ILD).

The Burden of Progressive Fibrosing Interstitial Lung Disease: A DELPHI Approach.

INTRODUCTION: The term progressive fibrosing interstitial lung disease (ILD) describes patients with fibrotic ILDs who, irrespective of the aetiology of the disease, show a progressive course of their disease despite current available (and non-licensed) treatment. Besides in idiopathic pulmonary fibrosis, little is known about management and the burden of patients with fibrotic ILD, particularly those with a progressive behaviour. METHODS: Using the Delphi method, 40 European experts in ILD management delivered information on management of (progressive) fibrosing ILD and on the impact of the disease on patients' quality of life (QoL) and healthcare resource utilisation (HCRU). Annual costs were calculated for progressive and non-/slow-progressive fibrosing ILD for diagnosis, follow-up management, exacerbation management, and end-of-life care based on the survey data. RESULTS: Physicians reported that progression in fibrosing ILD worsens QoL in both patients and their caregivers. Progression of fibrosing ILD was associated with a greater use of HCRU for follow-up visits and maintenance treatment compared with the non-/slow progression. The number of patients who suffered at least one acute exacerbation was reported to be more than three times higher in progressive fibrosing ILD patients than in patients with non-/slow-progressive fibrosing ILD. On average, annual estimated costs of progressive fibrosing ILD per patient were 1.8 times higher than those of the non-/slow-progressive form of the disease. CONCLUSIONS: Progression in fibrosing ILD causes a significant impact on QoL and HCRU and costs. These survey data underline the need for safe and effective therapies to slow the disease progression.

Quantitative computed tomography assessment for systemic sclerosis-related interstitial lung disease: comparison of different methods.

OBJECTIVES: To compare the previously defined six different histogram-based quantitative lung assessment (QLA) methods on high-resolution CT (HRCT) in patients with systemic sclerosis (SSc)-related interstitial lung disease (ILD). METHODS: The HRCT images of SSc patients with ILD were reviewed, and the visual ILD score (semiquantitative) and the severity of ILD (limited or extensive) were calculated. The QLA score of ILD was evaluated using the previously defined six different methods and parameters (different lung attenuation ranges, skewness, kurtosis, mean lung attenuation, and standard deviation [SD]). Pulmonary function tests (PFTs) were also performed on all patients. Relationships among variables were evaluated using Spearman's correlation coefficient (r). Diagnostic performance of quantitative methods for the ability to differentiate the limited from extensive ILD was calculated using ROC analysis. RESULTS: Fifty-five patients were included in the study. There was a significant correlation between all quantitative and semiquantitative measurement results (p < 0.0001). The QLA scores revealed a significant correlation with PFT results. The kurtosis value of the voxels between - 200 and - 1024 Hounsfield unit (HU) (Method-5) showed the best correlation with semiquantitative evaluation (r = - 0.740, p < 0.0001). The ROC analysis demonstrated the best performance of SD of the voxels between - 400 and - 950 HU (Method-6) for histogram analysis method and Method-3 (voxels between - 260 and - 600 HU were calculated as ILD) for CT density cutoff methods. CONCLUSIONS: All the QLA methods are applicable in assessing the ILD score in SSc patients and have potential importance to differentiate limited from extensive ILD. KEY POINTS: • Quantitative interstitial lung disease assessment helps clinicians to assess systemic sclerosis patients with interstitial lung disease. • Quantitative lung assessment methods are applicable in assessing the interstitial lung disease score in systemic sclerosis patients. • Quantitative lung assessment methods have potential importance in the management of patients.

Pulmonary flow assessment by phase-contrast MRI can predict short-term mortality of fibrosing interstitial lung diseases.

BACKGROUND: Phase-contrast magnetic resonance imaging (PC-MRI) can determine pulmonary hemodynamics non-invasively. Pulmonary hypertension causes changes in pulmonary hemodynamics and is a factor for acute exacerbation and death in interstitial lung diseases (ILD). PURPOSE: To determine associations between pulmonary hemodynamics measured by PC-MRI and short-term mortality in patients with ILD. MATERIAL AND METHODS: Pulmonary hemodynamics, measured by PC-MRI in 43 patients with ILD, were reviewed retrospectively. Evaluation parameters included heart rate, right cardiac output, average flow, average velocity, acceleration time, acceleration volume (AV), maximal change in flow rate during ejection (M), M/AV, maximum area, minimum area, and relative area change in the pulmonary artery (PA). All causes of death within one year from the day of the MRI examination were assessed by reviewing medical records. Associations between evaluation parameters and outcome were determined by univariate and multivariate Cox regression analysis. RESULTS: Six patients (13.9%) died by the one-year follow-up. Age (hazard ratio [HR] 1.116, 95% confidence interval [CI] 1.015-1.269), average flow (HR 0.932, 95% CI 0.870-0.984), average velocity (HR 0.778, 95% CI 0.573-0.976), right cardiac output (HR 0.870, 95% CI 0.758-0.967), AV (HR 0.840, 95% CI 0.669-0.985), M/AV (HR 1.008, 95% CI 1.001-1.014), and PA relative area change (HR 0.715, 95% CI 0.459-0.928) predicted death in univariate Cox analysis. Multivariate Cox analysis showed decreased right cardiac output (HR 0.547, 95% CI 0.160-0.912) and decreased PA relative area change (HR 0.538, 95% CI 0.177-0.922) were independently associated with death. CONCLUSION: Reduction in right cardiac output and decreased PA relative area change, detected by PC-MRI, were associated with increased mortality in ILD.

Ability of the COPD Assessment Test to evaluate the lung-specific quality of life in systemic sclerosis-associated interstitial lung disease.

INTRODUCTION: The COPD Assessment Test (CAT) is utilised to evaluate the treatment outcome regarding the health status in idiopathic interstitial pneumonia (IIP). However, the ability of the CAT to evaluate the lung-specific quality of life in systemic sclerosis-associated interstitial lung disease (SSc-ILD) is not established. Therefore, we investigated whether CAT scores can be used to evaluate SSc-ILD as they are for IIP. METHODS: A total of 150 patients with IIP or SSc-ILD who were evaluated by the CAT were retrospectively assigned to this study. Clinical data at the visit for the CAT were analysed. RESULTS: The forced vital capacity and distance walked during the 6-minute walk test (6MWD) were significantly correlated with the CAT score for SSc-ILD and IIP, and the CAT scores were similarly distributed in SSc-ILD and IIP. The CAT score of SSc-ILD patients was negatively affected by pulmonary arterial hypertension, but not by corticosteroids, which affected it in IIP patients. CAT scores of patients with either disease receiving home oxygen therapy were poor. In multiple regression analysis, pulmonary arterial hypertension and 6MWD were independent predictors for the CAT score in patients with SSc-ILD, while corticosteroid administration was selected as an independent factor in patients with IIP. CONCLUSIONS: Our study suggests that the CAT can be applied to evaluate the lung-specific quality of life in SSc-ILD similar to IIP regarding the pulmonary function, but it should be noted that pulmonary arterial hypertension in SSc-ILD influences the CAT score.

Assessment of interstitial lung disease in systemic sclerosis using the quantitative CT algorithm CALIPER.

Interstitial lung disease (ILD) remains a major cause of morbidity and mortality in systemic sclerosis (SSc). Study aim is to characterize and quantify SSc-ILD by using Computer-Aided Lung Informatics for Pathology Evaluation and Rating (CALIPER). Secondly, our objective is to evaluate which radiological pattern is predictive of lung function decline at 12 months follow-up. In the prospective study (IRB 5435), 66 SSc patients underwent high-resolution computerized tomography (HRCT) at baseline. HRCT was performed according to standard protocol using a CT 64GE light speed VCT power scanner. CALIPER classified lung parenchyma on volume units. Every volume unit was classified into radiological parenchymal patterns (honeycombing, reticular and ground glass). Pulmonary function tests (PFTs) were performed at baseline and after 12 months of follow-up. Cigarette smoking and other lung diseases unrelated to SSc are exclusion criteria. CALIPER analysis showed normal lung parenchyma 87.4 ± 9.8%, ground glass 2.8 ± 5.3%, reticular 4 ± 5.7%, and honeycombing 1 ± 1%. In multiple regression analysis, FEV1 (p < 0.0001), FVC (p = 0.001), and DLCO (p < 0.0001) measurements at baseline showed a negative correlation with the reticular pattern percentage. At follow-up, DLCO reduction showed a positive correlation (p < 0.001) with the percentage of ground glass pattern (r = 0.33, beta coefficient = 0.51). In the ROC curve analysis, ground glass score is a good predictor (0.75, p = 0.009; 95% CI 0.59-0.91) of DLCO worsening, defined as a decrease of more than 10% of DLCO. Using a cutoff ≥ 4.5 for ground glass score, the RR for DLCO worsening is 6.8 (p < 0.01; 95% CI 1.6-29.2). The results of this study show that CALIPER is useful not only for quantifying lung damage but also for assessing worsening PFTs, but larger studies are needed to confirm these preliminary data.Key Points• At baseline reticular pattern showed negative correlation with PFTs• At follow-up ground glass pattern predicts worsening of DLCO• CALIPER is a useful to quantify lung damage.

Quantitative assessment of interstitial lung disease in Sjögren's syndrome.

BACKGROUND: Interstitial lung disease (ILD) is a frequent manifestation of Sjögren's syndrome (SS), an autoimmune disease of salivary and lacrimal glands, and affects approximately 20% of patients. No clinical or serological features appear to be useful to predict its presence, severity or progression, and chest high-resolution computed tomography (CT) remains the gold standard for diagnosis. Semiquantitative CT (SQCT) based on visual assessment (Goh and Taouli scoring) can estimate ILD extent, although it is burdened by relevant intra- and interobserver variability. Quantitative chest CT (QCT) is a promising alternative modality to assess ILD severity. AIM: To determine whether QCT assessment can identify extensive or limited lung disease in patients with SS and ILD. METHODS: This multi-center, cross-sectional and retrospective study enrolled patients with SS and a chest CT scan. SQCT assessment was carried out in a blinded and centralized manner to calculate both Goh and Taouli scores. An operator-independent analysis of all CT scans with the open-source software platform Horos was used to evaluate the QCT indices. Patients were classified according to the extent of ILD and differences in QCT index distribution were investigated with non-parametric tests. RESULTS: From a total of 102 consecutive patients with SS, the prevalence of ILD was 35.3% (36/102). There was a statistically significant difference in QCT index distribution between the SS with ILD and SS without ILD groups (p<0.001). Moreover, SS-ILD patients with ILD >20% (by Goh score) had a QCT index statistically different from those with limited ILD extent (p<0.001). Finally, QCT indices showed a moderate-to-good correlation with the Goh and Taouli scores (from 0.44 to 0.65; p<0.001). CONCLUSIONS: QCT indices can identify patients with SS and ILD and discriminate those with lesser or greater lung disease.

Impact of Psychological Deficits and Pain on Physical Activity of Patients with Interstitial Lung Disease.

PURPOSE: The impact of psychological deficits and pain on physical activity has not been adequately studied in patients with fibrotic interstitial lung disease (ILD). We aimed to determine the association of depression, anxiety, sleep quality, and pain with physical activity in fibrotic ILD. METHODS: Waist ActiGraph activity monitors were worn for seven consecutive days to track step counts and moderate-to-vigorous physical activity (MVPA) minutes at baseline and 6-month follow-up. Psychological deficits and pain were assessed using the Hospital Anxiety and Depression Scale, the Pittsburgh Sleep Quality Index, and the Brief Pain Inventory. Multivariable linear regression was used to determine if each deficit independently predicted physical activity when adjusted for potential confounders. RESULTS: A total of 111 patients were recruited, with 91 of these patients completing the 6-month follow-up. Median step count and MVPA minutes were 3853 steps/day (interquartile range 2236-6805) and 87 (17-225) min/week at baseline, respectively, with no significant changes at follow-up. Borderline or abnormal depression and anxiety scores were present in 19% and 22% of patients, respectively. Poor sleep quality and moderate-to-severe pain were present in 61% and 9% of patients. Higher depression scores were associated with fewer baseline and follow-up step counts and lower MVPA minutes at follow-up on unadjusted analysis; higher pain severity scores were associated with fewer baseline step count. Pain severity remained an independent predictor of reduced step count after adjusting for patient's age, smoking status, ILD severity, and weather variables. CONCLUSIONS: Pain severity may be a potentially modifiable determinant of physical activity in patients with fibrotic ILD.

Performance of the COPD Assessment Test in patients with connective tissue disease-associated interstitial lung disease.

BACKGROUND: Patients with connective tissue disease-associated interstitial lung disease (CTD-ILD) often experience impaired health status. In daily clinical practice, a short and easy instrument for assessing health status would be useful to help better understand the patient's condition. The COPD Assessment Test (CAT) is a simple questionnaire about respiratory symptoms and their impact. We aimed to examine the CAT's performance characteristics and to generate data to support its reliability and validity in patients with CTD-ILD. METHODS: We used data from 132 CTD-ILD patients evaluated at Tosei General Hospital from July 2011 to July 2016 to assess the cross-sectional and longitudinal validity of the CAT. RESULTS: The mean age of the patients was 64.5 years and 87 (66%) were women. There were no significant differences in CAT score between any of the CTD subgroups. Internal consistency (Cronbach's α = 0.881) and repeatability (intraclass correlation coefficient [ICC] = 0.803) for the CAT score were acceptable. At baseline, CAT score was significantly associated with clinically meaningful measures of physiologic function, exercise capacity, and dyspnea. Change in CAT score over 6-12 months was also associated with change in other measures. In the distribution- and anchor-based analyses, the estimated minimal clinically important difference of CAT score was 1-4 points. CONCLUSION: These data support the validity and reliability of CAT as a sensitive measure for assessing health status in patients with CTD-ILD.

Quantitative Follow-Up Assessment of Patients with Interstitial Lung Disease by 3D-Curved High-Resolution CT Imaging Parallel to the Chest Wall.

We evaluated the progression of interstitial lung disease (ILD) by three-dimensional curved high-resolution computed tomography (3D-cHRCT) at a constant depth from the chest wall and compare the results to pulmonary function test (PFT) results on a follow-up assessment. We reviewed the patients with ILD who underwent HRCT and concurrent PFTs at least twice from April 2008 to December 2014. Forty-five patients with ILD were enrolled. 3D-cHRCT images of the lung at various depths from the chest wall were reconstructed, and total area (TA), high-attenuation area (HAA) >-500 HU, and %HAA ([HAA/TA] × 100) were calculated. The TA, HAA, and %HAA ratios (follow-up to baseline) were assessed for use in the diagnosis of physiologically progressive ILD (defined as; forced vital capacity [FVC] ratio <0.9 or %diffusing capacity of the lung for carbon monoxide [%DLCO] ratio <0.85 [follow-up to baseline]). Of all ratios obtained from 3D-cHRCT images at 5-30mm depths, the %HAA ratio at 20-mm had the largest area under the receiver operating characteristic curve (0.815, 95 % confidence interval 0.677-0.953). By univariate logistic regression analysis, TA, HAA, and %HAA ratios at 20-mm showed significant correlations with physiologically progressive ILD. 3D-cHRCT imaging performed in parallel with the chest wall offers novel quantitative parameters that are useful for following ILD.

Patients' perceptions and patient-reported outcomes in progressive-fibrosing interstitial lung diseases.

The effects of interstitial lung disease (ILD) create a significant burden on patients, unsettling almost every domain of their lives, disrupting their physical and emotional well-being and impairing their quality of life (QoL). Because many ILDs are incurable, and there are limited reliably-effective, life-prolonging treatment options available, the focus of many therapeutic interventions has been on improving or maintaining how patients with ILD feel and function, and by extension, their QoL. Such patient-centred outcomes are best assessed by patients themselves through tools that capture their perceptions, which inherently incorporate their values and judgements. These patient-reported outcome measures (PROs) can be used to assess an array of constructs affected by a disease or the interventions implemented to treat it. Here, we review the impact of ILD that may present with a progressive-fibrosing phenotype on patients' lives and examine how PROs have been used to measure that impact and the effectiveness of therapeutic interventions.

Rheumatological Assessment Is Important for Interstitial Lung Disease Diagnosis.

OBJECTIVE: Interstitial lung diseases (ILD) form a diverse group of parenchymal lung disorders. Currently, a multidisciplinary team (MDT) including pulmonologists, radiologists, and pathologists is the gold standard for ILD diagnosis. Recently, additional subtypes of connective tissue disease (CTD)-ILD with autoimmune features were defined, making the rheumatological assessment increasingly important. We aimed to assess the effect of adding a rheumatologist to the MDT for routine rheumatology assessment. METHODS: A prospective study that assessed newly diagnosed ILD patients by 2 parallel blinded arms; all patients were evaluated by both MDT (e.g., history, physical examination, blood tests, pulmonary function tests, and biopsies, if needed) and a rheumatologist (e.g., history, physical examination, blood and serological tests). RESULTS: Sixty patients were assessed with the mean age of 67.3 ± 12 years, 55% male, and 28% smokers. The rheumatological assessment reclassified 21% of the idiopathic pulmonary fibrosis as CTD. Moreover, the number of CTD-ILD with autoimmune features was increased by 77%. These included antineutrophil cytoplasmic antibody-associated vasculitis, antisynthetase syndrome, and IgG4-related ILD. Retrospectively, rheumatological evaluation could have saved 7 bronchoscopies and 1 surgical biopsy. CONCLUSION: Adding routine rheumatology assessments could significantly increase diagnostic accuracy and reduce invasive procedures.

Multiparametric Magnetic Resonance Imaging in the Assessment of Pulmonary Hypertension: Initial Experience of a One-Stop Study.

INTRODUCTION: Our goal was to assess the diagnostic performance of magnetic resonance imaging (MRI) as a single method to diagnose pulmonary hypertension (PH) compared to right heart catheterization (RHC), computed tomography (CT), and ventilation/perfusion (V/Q) scintigraphy. METHODS: We identified 35 patients diagnosed with PH by RHC in our institution who have also undergone a CT, a scintigraphy, and an MRI within a month. All cases were discussed in multidisciplinary meetings. We performed correlations between the MRI-derived hemodynamic parameters and those from RHC. The sensitivity and specificity of MRI were determined to identify its diagnostic performance to identify chronic thromboembolic pulmonary hypertension (CTEPH) and interstitial lung disease PH. The gold standard reference for the diagnosis of CTEPH and ILD was based on a review of multimodality imaging (V/Q scintigraphy and CT scan) and clinical findings. RESULTS: Our results showed a good correlation between the hemodynamic parameters of cardiac MRI and RHC. Pulmonary vascular resistance had the best correlation between both methods (r = 0.923). The sensitivity and specificity of MRI to diagnose CTEPH was 100 and 96.8%, respectively. For the ILD-related PH, the MRI yielded a sensitivity of 60.0% and a specificity of 100%. Additionally, cardiac MRI was able to confirm all cases of PAH due to congenital heart disease initially detected by echocardiography. CONCLUSIONS: MRI represents a promising imaging modality as an initial, single-shot study, for patients with suspected PH with the advantages of being non-invasive and having no radiation exposure.

Validity of Ultrasound Lung Comets for Assessment of the Severity of Interstitial Pneumonia.

OBJECTIVES: Ultrasound (US) lung comets are often observed in patients with interstitial lung disease or congestive heart failure, but few studies have explored the clinical importance of US lung comets in patients with the former condition. We explored whether the US lung comet number could be used to assess the severity of interstitial pneumonia. METHODS: Forty stable patients with interstitial pneumonia were examined. Lung comets evident on transthoracic US imaging in 12 selected regions of the posterior chest wall were analyzed. We defined lung comets accompanied by thickened and irregular pleural lines as interstitial US lung comets; these predominated in patients with interstitial pneumonia. The total number of interstitial US lung comets was correlated with the data from chest high-resolution computed tomography, pulmonary function tests, serologic tests, and the 6-minute walk test. RESULTS: The 40 patients included 16 with idiopathic pulmonary fibrosis and 24 with nonspecific interstitial pneumonia. Thirty-four patients had interstitial US lung comets, which were more common in the lower than the upper lung area. Good correlations were evident between the lung comet number and the extent of the reticular pattern on chest high-resolution computed tomography (r = 0.710; P < .01), predicted forced vital capacity (r = -0.614; P < .01), and lung diffusion capacity for carbon monoxide (r = -0.577; P < .01). Notably, the lung comet number had a strong negative correlation with the percutaneous oxygen saturation level after the 6-minute walk test (r = -0.751; P < .01). CONCLUSIONS: The number of interstitial US lung comets evident on transthoracic US imaging may be a valuable marker of disease severity in patients with interstitial pneumonia.

Utilization of non-invasive imaging tools for assessment of peripheral skeletal muscle size and composition in chronic lung disease: A systematic review.

OBJECTIVES: Non-invasive imaging modalities allow for detailed assessment of peripheral skeletal muscle wasting, which is associated with increased morbidity and mortality in chronic lung disease. Given the increased utilization of imaging tools, a systematic review was conducted using PRISMA guidelines to describe the modalities and acquisition techniques used to evaluate skeletal muscle in chronic lung disease and assess the relationships of muscle size and composition with strength, physical performance, structural alterations and clinical outcomes. METHODS: Six electronic databases were searched (inception-May 2017) to identify prospective studies measuring peripheral skeletal muscle size or composition using computed tomography (CT), magnetic resonance imaging/spectroscopy (MRI/MRS), or ultrasound (US) in adult chronic lung disease patients. RESULTS: Fifty-eight articles were included, which utilized: CT (n = 26), MRI/MRS (n = 16) and US (n = 16) in 2254 participants. All studies measured muscle size, predominantly of the lower extremity (n = 53), and only nine assessed muscle composition (i.e. fat infiltration) mainly with CT or MRI/MRS (n = 7). Thigh muscle size had a significant association with strength (r = 0.43-0.83, n = 13/14 studies), 6-min walk distance (r = 0.60-0.62, n = 3/6) and physical activity (r = 0.30-0.82, n = 3). Thigh muscle atrophy was independently associated with increased re-hospitalization (n = 1) and mortality (n = 3). Increased muscle fat infiltration had a moderate association with reduced physical performance partly related to increased anaerobic metabolism, but its prognostic utility was not assessed. CONCLUSION: Imaging modalities are valuable tools for the characterization of skeletal muscle dysfunction in chronic lung disease in clinical and research settings. The use of muscle imaging as a prognostic marker is promising and requires further study.

Novel Assessment of Interstitial Lung Disease Using the "Computer-Aided Lung Informatics for Pathology Evaluation and Rating" (CALIPER) Software System in Idiopathic Inflammatory Myopathies.

PURPOSE: To evaluate the correlation between measurements from quantitative thoracic high-resolution CT (HRCT) analysis with "Computer-Aided Lung Informatics for Pathology Evaluation and Rating" (CALIPER) software and measurements from pulmonary function tests (PFTs) in patients with idiopathic inflammatory myopathies (IIM)-associated interstitial lung disease (ILD). METHODS: A cohort of patients with IIM-associated ILD seen at Mayo Clinic was identified from medical record review. Retrospective analysis of HRCT data and PFTs at baseline and 1 year was performed. The abnormalities in HRCT were quantified using CALIPER software. RESULTS: A total of 110 patients were identified. At baseline, total interstitial abnormalities as measured by CALIPER, both by absolute volume and by percentage of total lung volume, had a significant negative correlation with diffusing capacity for carbon monoxide (DLCO), total lung capacity (TLC), and oxygen saturation. Analysis by subtype of interstitial abnormality revealed significant negative correlations between ground glass opacities (GGO) and reticular density (RD) with DLCO and TLC. At one year, changes of total interstitial abnormalities compared with baseline had a significant negative correlation with changes of TLC and oxygen saturation. A negative correlation between changes of total interstitial abnormalities and DLCO was also observed, but it was not statistically significant. Analysis by subtype of interstitial abnormality revealed negative correlations between changes of GGO and RD and changes of DLCO, TLC, and oxygen saturation, but most of the correlations did not achieve statistical significance. CONCLUSION: CALIPER measurements correlate well with functional measurements in patients with IIM-associated ILD.