BACKGROUND: Advanced heterogeneous emphysema with hyperinflation impacts exercise tolerance in COPD. Bronchoscopic lung volume reduction using Zephyr endobronchial valves (EBVs) has been shown to improve lung function in patients with heterogeneous emphysema. It is unclear whether the target lobe perfusion of patients receiving EBV therapy impacts exercise tolerance as measured by the 6-min walk test distance (6MWTD). METHODS: We performed a retrospective analysis on the treatment group of the Endobronchial Valve for Emphysema Palliation Trial (VENT) to evaluate the impact of perfusion, measured by 99mTc-MAA-perfusion scintigraphy, on the 6-month improvement in 6MWTD. A mixed-model analysis was performed for the treatment outcome, adjusting for other variables such as age, target lobe position, fissure integrity, BMI, sex, destruction score, and lobar exclusion.

Imaging has become a prevalent tool in the diagnosis and treatment of many diseases, providing a unique in vivo, multi-scale view of anatomic and physiologic processes. With the increased use of imaging and its progressive technical advances, the role of imaging informatics is now evolving--from one of managing images, to one of integrating the full scope of clinical information needed to contextualize and link observations across phenotypic and genotypic scales. Several challenges exist for imaging informatics, including the need for methods to transform clinical imaging studies and associated data into structured information that can be organized and analyzed. We examine some of these challenges in establishing imaging-based observational databases that can support the creation of comprehensive disease models. The development of these databases and ensuing models can aid in medical decision making and knowledge discovery and ultimately, transform the use of imaging to support individually-tailored patient care.

PURPOSE: The purpose of this study is to adapt an equivalent source model originally developed for conventional CT Monte Carlo dose quantification to the radiation oncology context and validate its application for evaluating concomitant dose incurred by a kilovoltage (kV) cone-beam CT (CBCT) system integrated into a linear accelerator. METHODS: In order to properly characterize beams from the integrated kV CBCT system, the authors have adapted a previously developed equivalent source model consisting of an equivalent spectrum module that takes into account intrinsic filtration and an equivalent filter module characterizing the added bowtie filtration. An equivalent spectrum was generated for an 80, 100, and 125 kVp beam with beam energy characterized by half-value layer measurements. An equivalent filter description was generated from bowtie profile measurements for both the full- and half-bowtie. Equivalent source models for each combination of equivalent spectrum and filter were incorporated into the Monte Carlo software package MCNPX. Monte Carlo simulations were then validated against in-phantom measurements for both the radiographic and CBCT mode of operation of the kV CBCT system. Radiographic and CBCT imaging dose was measured for a variety of protocols at various locations within a body (32 cm in diameter) and head (16 cm in diameter) CTDI phantom. The in-phantom radiographic and CBCT dose was simulated at all measurement locations and converted to absolute dose using normalization factors calculated from air scan measurements and corresponding simulations. The simulated results were compared with the physical measurements and their discrepancies were assessed quantitatively.

The national cost of cancer care is projected to reach $173 billion by 2020, increasing from $125 billion in 2010. This steep upward cost trajectory has placed enormous an financial burden on patients, their families, and society as a whole and raised major concern about the ability of the health care system to provide and sustain high-quality cancer care. To better understand the cost drivers of cancer care and explore approaches that will mitigate the problem, the National Cancer Policy Forum of the Institute of Medicine held a workshop entitled "Delivering Affordable Cancer Care in the 21st Century" in October 2012. Workshop participants included bioethicists, health economists, primary care physicians, and medical, surgical, and radiation oncologists, from both academic and community settings. All speakers expressed a sense of urgency about the affordability of cancer care resulting from the future demographic trend as well as the high cost of emerging cancer therapies and rapid diffusion of new technologies in the absence to evidence indicating improved outcomes for patients. This article is our summary of presentations at the workshop that highlighted the overuse and underuse of screening, treatments, and technologies throughout the cancer care continuum in oncology practice in the United States.

Pulmonary hypertension (PH) may complicate parenchymal lung disease, specifically interstitial lung diseases and chronic obstructive pulmonary disease, and uniformly increases the mortality risk. The epidemiology and degree of PH is variable and unique to the underlying lung disease. The clinician should exercise a high index of suspicion for PH complicating parenchymal lung disease especially given the nonspecific symptomatology and the limitations of echocardiography in this patient population. In general, PH-specific therapies in this setting have been poorly studied, with concern for increased shunting and/or ventilation/perfusion (V/Q) mismatch and resultant hypoxemia. A better understanding of the mechanisms underlying PH related to parenchymal lung disease may lead to novel pharmacological targets to prevent or treat this serious complication.

BACKGROUND: The National Lung Screening Trial was conducted to determine whether three annual screenings (rounds T0, T1, and T2) with low-dose helical computed tomography (CT), as compared with chest radiography, could reduce mortality from lung cancer. We present detailed findings from the first two incidence screenings (rounds T1 and T2). METHODS: We evaluated the rate of adherence of the participants to the screening protocol, the results of screening and downstream diagnostic tests, features of the lung-cancer cases, and first-line treatments, and we estimated the performance characteristics of both screening methods.

Dyspnea, described as breathlessness or shortness of breath, is usually caused by cardiopulmonary disease. The role of imaging in chronic dyspnea (>1 mo in duration) with suspected pulmonary origin is reviewed as suggested by the American College of Radiology Appropriateness Criteria Expert Panel on Thoracic Imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

There has been increasing interest in developing novel pulmonary biomarkers to assist in drug and device development in the setting of patients with chronic obstructive pulmonary disease and diffuse parenchymal lung disease. In this review we discuss which computed tomography (CT)-based biomarkers are currently being implemented and the challenges inherent in their development, validation, and implementation in multicenter trials. CT scans provide valuable information about lung structure and function but face challenges with respect to standardization across multiple sites and time points; in addition, the concern around radiation has to be considered. There is relatively little information about how any of these biomarkers relate to other clinical outcomes such as progression of disease, severity of disease, clinical subtypes, or response to therapy. Additional information is also needed about the variability in these measurements. In the future, CT biomarkers may be useful in predicting disease progression, in indicating disease instability, and in predicting response to current and novel therapies, many of which are now under development.

PURPOSE: Ensemble segmentation methods combine the segmentation results of individual methods into a final one, with the goal of achieving greater robustness and accuracy. The goal of this study was to develop an ensemble segmentation framework for glioblastoma multiforme tumors on single-channel T1w postcontrast magnetic resonance images. METHODS: Three base methods were evaluated in the framework: fuzzy connectedness, GrowCut, and voxel classification using support vector machine. A confidence map averaging (CMA) method was used as the ensemble rule.

Pulmonary hypertension (PH) may be idiopathic or related to a variety of diseases. The diagnosis, accurate assessment of etiology and severity, prognosis, treatment response, and follow-up of PH can be achieved using a diverse set of diagnostic examinations. In this review, the role of imaging in the evaluation of PH as suggested by the American College of Radiology Appropriateness Criteria Expert Panel on Thoracic Imaging has been discussed. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The development and review of the guidelines include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

We present a case of pulmonary alveolar proteinosis (PAP) initially diagnosed 28 months after left single-lung transplantation for idiopathic pulmonary fibrosis. The diagnosis was based upon the presence of periodic acid-Schiff (PAS)-positive and surfactant immunostain-positive acellular lipoproteinaceous material within alveoli seen on transbronchial biopsy as well as in bronchoalveolar lavage fluid. The patient eventually also displayed a characteristic "crazy paving" pattern on radiographic imaging. Granulocyte macrophage-colony stimulating factor antibodies were negative, consistent with secondary PAP. PAP is a rare interstitial lung disease with only a few reported cases occurring after lung transplantation. The etiology is thought to be related to a defect in macrophage function caused by immunosuppression. Reduced immunosuppression has been associated with stabilization, but not reversal, of the condition in the case reported here. PAP is an exceptionally rare cause of dyspnea and radiographic infiltrates after lung transplantation and may be related to toxicity of immune-suppressive medications.

BACKGROUND: Cabozantinib is an oral MET/VEGFR2 inhibitor. A recent phase II study of cabozantinib (100 mg daily) showed improved bone scans in subjects with metastatic castration-resistant prostate cancer (mCRPC), but adverse events (AE) caused frequent dose reductions. This study was designed to determine the efficacy and tolerability of cabozantinib at lower starting doses. EXPERIMENTAL DESIGN: An adaptive design was used to determine the lowest active daily dose among 60, 40, and 20 mg. The primary endpoint was week 6 bone scan response, defined as ≥30% decrease in bone scan lesion area. The secondary endpoint was change in circulating tumor cells (CTC).

National Lung Screening Trial Research Team, Church TR, Black WC, Aberle DR, Berg CD, Clingan KL, Duan F, Fagerstrom RM, Gareen IF, Gierada DS, Jones GC, Mahon I, Marcus PM, Sicks JD, Jain A, Baum S. BACKGROUND: Lung cancer is the largest contributor to mortality from cancer. The National Lung Screening Trial (NLST) showed that screening with low-dose helical computed tomography (CT) rather than with chest radiography reduced mortality from lung cancer. We describe the screening, diagnosis, and limited treatment results from the initial round of screening in the NLST to inform and improve lung-cancer-screening programs. METHODS: At 33 U.S. centers, from August 2002 through April 2004, we enrolled asymptomatic participants, 55 to 74 years of age, with a history of at least 30 pack-years of smoking. The participants were randomly assigned to undergo annual screening, with the use of either low-dose CT or chest radiography, for 3 years. Nodules or other suspicious findings were classified as positive results. This article reports findings from the initial screening examination.

The National Lung Screening Trial (NLST) has provided compelling evidence of the efficacy of lung cancer screening using low-dose helical computed tomography (LDCT) to reduce lung cancer mortality. The NLST randomized 53,454 older current or former heavy smokers to receive LDCT or chest radiography (CXR) for three annual screens. Participants were observed for a median of 6.5 years for outcomes. Vital status was available in more than 95% of participants. LDCT was positive in 24.2% of screens, compared with 6.9% of CXRs; more than 95% of all positive LDCT screens were not associated with lung cancer. LDCT detected more than twice the number of early-stage lung cancers and resulted in a stage shift from advanced to early-stage disease. Complications of LDCT screening were minimal. Lung cancer-specific mortality was reduced by 20% relative to CXR; all-cause mortality was reduced by 6.7%. The major harms of LDCT are radiation exposure, high false-positive rates, and the potential for overdiagnosis. This review discusses the risks and benefits of LDCT screening as well as an approach to LDCT implementation that incorporates systematic screening practice with smoking cessation programs and offers opportunities for better determination of appropriate risk cohorts for screening and for better diagnostic prediction of lung cancer in the setting of screen-detected nodules. The challenges of implementation are considered for screening programs, for primary care clinicians, and across socioeconomic strata. Considerations for future research to complement imaging-based screening to reduce the burden of lung cancer are discussed.

Daily routine chest radiographs in the intensive care unit (ICU) have been a tradition for many years. Anecdotal reports of misplacement of life support items, acute lung processes, and extra pulmonary air collections in a small number of patients served as a justification for routine chest radiographs in the ICU. Having analyzed this practice, the ACR Appropriateness Criteria Expert Panel on Thoracic Imaging has made the following recommendations:

• When monitoring a stable patient or a patient on mechanical ventilation in the ICU, a portable chest radiograph is appropriate for clinical indications only.
• It is appropriate to obtain a chest radiograph after placement of an endotracheal tube, central venous line, Swan-Ganz catheter, nasogastric tube, feeding tube, or chest tube.

The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. The strongest data contributing to these recommendations were derived from a meta-analysis of 8 trials comprising 7,078 ICU patients by Oba and Zaza [1].

AIM: To assess the diagnostic value of coronary dual-source computed tomography (DSCT) as a comprehensive, non-invasive tool in the preoperative cardiac evaluation of patients undergoing bariatric surgery. MATERIALS AND METHODS: Thirty consecutive obese [average body mass index (BMI): 45 ± 7.6, range: 35-59] patients (24 women; six men; median age: 52 ± 15 years) were enrolled in this institutional review board (IRB)-approved, Health Insurance Portability and Accountability Act of 1996 (HIPAA)-compliant prospective study. Calcium scoring (CaS) and electrocardiography (ECG)-gated images of the coronary arteries were obtained with a large body habitus protocol (120 kV; 430 mAs; 100 ml iodinated contrast medium at 7 ml/s injection rate) on a DSCT machine. Qualitative (four-point: 1 = excellent to 4 = not delineable) coronary segmental analysis, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) measurements were performed. The presence and degree of vascular disease (four-grade scale: mild to severe) was correlated with CaS and cardiovascular (CV) risk stratification blood tests. In patients with severe stenosis (>70%), findings were compared with cardiac nuclear medicine imaging (single photon-emission computed tomography; SPECT) imaging.

Now the leading subtype of lung cancer, adenocarcinoma received a new classification in 2011. For tumors categorized previously as bronchioloalveolar carcinoma (BAC), criteria and terminology had not been uniform, so the 2011 classification provided four new terms: (a) adenocarcinoma in situ (AIS), representing histopathologically a small (≤3-cm), noninvasive lepidic growth, which at computed tomography (CT) is usually nonsolid; (b) minimally invasive adenocarcinoma, representing histopathologically a small ( ≤3-cm) and predominantly lepidic growth that has 5-mm or smaller invasion, which at CT is mainly nonsolid but may have a central solid component of up to approximately 5 mm; (c) lepidic predominant nonmucinous adenocarcinoma, representing histopathologically invasive adenocarcinoma that shows predominantly lepidic nonmucinous growth, which at CT is usually part solid but may be nonsolid or occasionally have cystic components; and (d) invasive mucinous adenocarcinoma, histopathologically showing lepidic growth as its predominant component, which at CT varies widely from solid to mostly solid to part solid to nonsolid and may be single or multiple (when multifocal, it was formerly called multicentric BAC). In addition, new histopathologic subcategories of acinar, papillary, micropapillary, and solid predominant adenocarcinoma are now described, all as nonmucinous, predominantly invasive, may include a small lepidic component, and at CT are usually solid but may include a small nonsolid component. The micropapillary subtype has a poorer prognosis than the other subtypes. In addition, molecular genetic correlations for the subcategories of adenocarcinoma of the lung are now a topic of increasing interest. As the new classification enters common use, further descriptions of related correlations can be anticipated. © RSNA, 2012.

The solitary pulmonary nodule (SPN) is a common medical problem for which management can be quite complex. Imaging remains at the center of management of SPNs, and computed tomography is the primary modality by which SPNs are characterized and followed up for stability. This manuscript summarizes the American College of Radiology Appropriateness Criteria for radiographically detected solitary pulmonary nodules and briefly reviews the various imaging techniques available. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.