Incidence of Interstitial Lung Abnormalities: The MESA Lung Study.

The incidence of newly developed interstitial lung abnormalities (ILA) and fibrotic ILA have not been previously reported.Trained thoracic radiologists evaluated 13 944 cardiac CT scans for the presence of ILA in 6197 Multi-Ethnic Study of Atherosclerosis longitudinal cohort study participants >45 years of age from 2000 to 2012. 5% of the scans were re-read by the same or a different observer in a blinded fashion. After exclusion of participants with ILA at baseline, incidence rates and incidence rate ratios for ILA and fibrotic ILA were calculated.The intra-reader agreement of ILA was 92.0% (Gwet AC1=0.912, ICC=0.982) and the inter-reader agreement of ILA was 83.5% (Gwet AC1=0.814; ICC=0.969). Incidence of ILA and fibrotic ILA was estimated to be 13.1 cases/1000 person-years and 3.5/1000 person-years, respectively. In multivariable analyses, age (HR 1.06 (1.05, 1.08), p <0.001; HR 1.08 (1.06, 1.11), p <0.001), high attenuation area (HAA) at baseline (HR 1.05 (1.03, 1.07), p <0.001; HR 1.06 (1.02, 1.10), p=0.002), and the MUC5B promoter SNP (HR 1.73 (1.17, 2.56) p=0.01; HR 4.96 (2.68, 9.15), p <0.001) were associated with incident ILA and fibrotic ILA, respectively. Ever smoking (HR 2.31 (1.34, 3.96), p= 0.002) and an IPF polygenic risk score (HR 2.09 (1.61-2.71), p<0.001) were associated only with incident fibrotic ILA.Incident ILA and fibrotic ILA were estimated by review of cardiac imaging studies. These findings may lead to wider application of a screening tool for atherosclerosis to identify preclinical lung disease.

Primary Intrathoracic Sarcomas: A Review of Cross-sectional Imaging and Pathology.

The most common sarcomas in the thorax are metastasis from an extrathoracic primary malignancy. Primary intrathoracic sarcomas are rare albeit aggressive malignancies that are diagnosed on histopathology. Although a few imaging characteristics have been described that are common to sarcomas, it is still a diagnosis of exclusion as other tumors are much more common. Like elsewhere, primary thoracic sarcomas are also classified according to their histologic features. They are a rare group of tumors that can arise from the mediastinal structures, lung, pleura, or chest wall. On imaging, differentiating these from more common malignancies like lung cancer is difficult and often requires multimodality workup and tissue sampling. A few sarcomas are very specific to their locations, such as angiosarcoma in the right atrium, leiomyosarcoma in the pulmonary artery, where imaging has high accuracy for the diagnosis. Despite being nonspecific in a majority of cases, imaging plays a pivotal role in determining the organ of origin, tumor extent, invasion of adjacent structures, and thus help to assess the surgical resectability. Although sarcomas arising from chest wall are the most common primary sarcomas in the chest, they are excluded from this review to focus only on primary intrathoracic sarcomas. The article provides a comprehensive imaging and pathology review of the rare primary intrathoracic sarcomas, including but not limited to angiosarcoma, Kaposi sarcoma, fibrosarcoma, malignant transformation of fibrous tumor of pleura, sarcomatoid mesothelioma, leiomyosarcoma, and malignant small round blue cell tumors.Key points:Primary intrathoracic sarcomas are rare but clinically important.Imaging helps to determine local extent, invasion, metastases and appropriate site/mode of biopsy.Role of pathology is paramount in diagnosis and guiding treatment based on immunogenetic/molecular typing.

Co-existent Epicardial Paraganglioma and Anterior Mediastinal Thymoma.

Thymoma and paraganglioma are known causes of mediastinal masses, the latter being extremely rare. Thymomas arise from remnant thymic tissue in the anterior mediastinum; whereas, thoracic paragangliomas arise from para-aortic or para-vertebral sympathetic chain ganglion (derivatives of embryonic neural crest) in the middle or posterior mediastinum. We report a case of a middle-aged woman with two mediastinal masses, originally believed to be a single tumor or primary malignancy with adjacent metastasis on Computed Tomography (CT) that were further delineated with Magnetic Resonance Imaging (MRI) and [68Ga]-DOTA-(Tyr3)-octreotate (DOTA-TATE) Positron Emission Tomography-Computed Tomography (PET-CT) and surgical pathology as two distinct entities: left epicardial paraganglioma and anterior mediastinal thymoma. A comprehensive discussion of both entities is included.

Incidentally detected ectopic thyroid in juxta cardiac location-Imaging and pathology.

Ectopic thyroid gland is a developmental anomaly that results from the arrest of thyroid tissue along its path of descent from the floor of mouth to the pre tracheal position in the lower neck. It is typically found along the thyroglossal duct with the base of the tongue being the most common site. Apart from mediastinal extension of goiter, the incidence of true intrathoracic ectopic thyroid tissue is rare. Presence of ectopic thyroid has been reported not only in the chest but also in the abdomen and pelvis. Pericardial and intracardiac locations are extremely uncommon and right ventricle location is predominant among the described cases. We describe a case of incidentally detected ectopic thyroid tissue in a rarer location-adjacent to the left atrium. The patient, who had undergone a nephrectomy for renal oncocytoma 5 years ago, presented with unintentional weight loss and left sided flank pain, prompting a workup to rule out abdominal malignancy. Findings on the computed tomography (CT) scan of the abdomen and pelvis prompted further investigation including a chest CT which showed a heterogeneously enhancing mass near the left atrium. Given its location, further radiological investigations played an important role in eliminating the differential diagnosis of paraganglioma. The mass was surgically resected and discovered to be a hyperplastic thyroid nodule on histologic examination.

The relationship of cancer characteristics and patient outcome with time to lung cancer diagnosis after an abnormal screening CT.

PURPOSE: The National Lung Screening Trial (NLST) demonstrated a reduction in lung cancer and all-cause mortality with low-dose CT (LDCT) screening. The aim of our study was to examine the time to diagnosis (TTD) of lung cancer in the LDCT arm of the NLST and assess its relationship with cancer characteristics and survival. METHODS: The subjects (N = 462) with a positive baseline screen and subsequent lung cancer diagnosis within 3 years were evaluated by data and image review to confirm the baseline abnormality. The cases were analysed for the relationship between TTD and imaging features, cancer type, stage and survival for 7 years from baseline screen. RESULTS: Cancer was judged to be present at baseline in 397/462 cases. The factors that showed significant association (p value trend less than 0.05) with longer TTD included smaller nodule size, pure ground glass nodules (GGNs), smooth/lobulated margins, stages I/II, adenocarcinoma, and decreasing lung cancer mortality. The logistic regression model for lung cancer death showed significant inverse relationships with size less than 20 mm (OR = 0.32), pure GGNs (OR = 0.24), adenocarcinoma (OR = 0.57) and direct relationship with age (OR = 1.4). CONCLUSION: TTD after a positive LDCT screen in the NLST showed a strong association with imaging features, stage and mortality. KEY POINTS: • NLST observed variable time to lung cancer diagnosis from positive baseline screen. • Time to diagnosis was associated with imaging features, cancer type and stage. • In univariate but not multivariate analysis, longer TTD correlated with decreased mortality.

Thoracic Imaging After Bariatric Surgery.

Obesity and its association with long-term health problems constitutes one of the major challenges in medicine. Though diet regulation and exercise are the primary treatment strategies, surgery is the most reliable long-term solution. Although bariatric surgical complications continue to decline, prompt recognition is essential to optimize patient outcomes. Despite their relative rarity, it is important to recognize thoracic complications, as several of these can result in severe morbidity and mortality. This article describes common bariatric surgical procedures performed, their expected postoperative appearances, and intrathoracic complications.

Comprehensive Imaging Review of the Superior Vena Cava.

The superior vena cava (SVC) is the largest central systemic vein in the mediastinum. Imaging (ie, radiography, computed tomography [CT], magnetic resonance [MR] venography, and conventional venography) plays an important role in identifying congenital variants and pathologic conditions that affect the SVC. Knowledge of the basic embryology and anatomy of the SVC and techniques for CT, MR imaging, and conventional venography are pivotal to accurate diagnosis and clinical decision making. Congenital anomalies such as persistent left SVC, partial anomalous pulmonary venous return, and aneurysm are asymptomatic and may be discovered incidentally in patients undergoing imaging evaluation for associated cardiac abnormalities or other indications. Familiarity with congenital abnormalities is important to avoid image misinterpretation. Acquired abnormalities such as intrinsic and extrinsic strictures, fibrin sheath, thrombus, primary neoplasms, and trauma can produce mild narrowing to complete occlusion, the latter leading to SVC syndrome. Each imaging modality plays a role in evaluation of the SVC, helping to determine the site, extent, and cause of pathologic conditions and guide appropriate management. Commonly performed interventional procedures for fibrin sheath and benign and malignant strictures include low-dose thrombolytic infusion, fibrin sheath disruption, venous angioplasty, and stent placement.

Visual scoring of coronary artery calcification in lung cancer screening computed tomography: association with all-cause and cardiovascular mortality risk.

OBJECTIVE: Current and former smokers are at an increased risk for lung cancer and cardiovascular disease (CVD). We investigated two methods of visual scoring of coronary artery calcium on lung cancer screening computed tomography (CT) to predict cardiovascular and all-cause mortality. PARTICIPANTS AND METHODS: Cases were 1000 participants, age 55-74 years, enrolled in the National Lung Screening Trial CT arm who died during the study. An equal number of participants alive at the end of the study (controls) were matched in terms of sex, CT scanner vendor, and model, and 5-year age and smoking pack-years group. Coronary calcium was measured visually by three readers using two semiquantitative scoring schemes. Conditional logistic regression was used to analyze the association between the presence and the extent of coronary calcium and all-cause and cardiovascular mortality, stratified on matching criteria. RESULTS: Cases and controls were well matched for age (64±6 vs. 64±5, P=0.95) and mean pack-years smoking (61±24 vs. 62±24, P=1.0). Cases were significantly more likely to have coronary calcium than controls (85 vs. 77%, P<0.001). Having any calcium was associated with an increased risk for CVD mortality using either visual scoring method (odds ratio 3.4, 95% confidence interval 2.0-5.6, P<0.001, and odds ratio 3.3, 95% confidence interval 2.0-5.6, P<0.001). CONCLUSION: Visual scoring of coronary calcium predicts all-cause and CVD mortality in National Lung Screening Trial participants, independent of current versus former smoking status. Visual coronary calcium scoring in low-dose CT scans helps identify individuals at high risk for mortality who may benefit from further CVD prevention.

Imaging biliary strictures--a pictorial review.

The diagnosis of biliary diseases may be delayed or missed because of an unpredictable clinical course and presentation. Some biliary diseases carry the risk of morbidity and mortality and are difficult to treat. The purpose of this article is to revisit the various causes and the appearances of biliary strictures on different imaging modalities and to emphasize the role of magnetic resonance imaging (MRI) with magnetic resonance cholangiopancreatography (MRCP) in their evaluation compared with endoscopic retrograde cholangiopancreatography. MRI with MRCP is advantageous to endoscopic retrograde cholangiopancreatography for being a 1-stop shop to provide biliary, soft tissue, and vascular information that is helpful for planning intervention or surgery. Thus it serves as a superb imaging modality for the evaluation of biliary strictures.

Laparoscopic adjustable gastric banding: what radiologists need to know.

Laparoscopic adjustable gastric banding (LAGB) is performed with increasing frequency for the management of morbid obesity. Although LAGB is less invasive than other bariatric surgical procedures, it is associated with various complications that may lead to nonspecific abdominal symptoms several months or years after the procedure. Because complications of LAGB may be encountered incidentally at imaging for other indications, all radiologists should be familiar with the appearances of correctly positioned and malpositioned gastric bands, normal and abnormal appearances of the postprocedural pouch and stomach, and imaging features suggestive or indicative of early or delayed complications of LAGB. Familiarity with the techniques and systems currently approved by the Food and Drug Administration for use in this procedure may help radiologists detect postoperative complications and guide their management. Both commercially available systems include a silicone gastric band with an inflatable inner surface, a reservoir port, and a tube that connects the port to the gastric band. All these components of LAGB systems should be visible at radiologic imaging; however, older models of gastric bands may not be radiopaque and therefore may not be depicted on images. The most common complications of LAGB are gastric band slippage and associated pouch dilatation, intragastric erosion of the band, gastric perforation, and abscess formation. Complications that occur with less frequency include tube migration, tube disconnection, port-site infection, and small bowel obstruction.