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Coronary artery calcium scoring (CACS) is a standard imaging tool to predict future cardiac events in asymptomatic subjects with intermediate Framingham risk score (FRS) due to its high accuracy for detecting coronary artery disease (CAD) [1]. In fact, the recently published 2013 guidelines of the AHA/ACC suggest an additional role for CACS in certain asymptomatic patients who are being considered for statin therapy but who are not included in four major statin benefit groups [2]. Notwithstanding these statements, it is undeniable that coronary CTA provides clearer anatomic definition of CAD than CACS and thus may have a role in screening for individuals at risk for CAD. The greatest advantage of coronary CTA over CACS is in visualization of the extent and type of coronary plaque. It has been estimated that CACS identifies only 20 % of total plaque volume that is present histologically [3]. Not only does coronary CTA visualize more of the total plaque amount, but it can provide superior information as to its location, whether the plaque is calcified, non-calcified or mixed, obstructive or non-obstructive and the status of vessel remodeling. Coronary CTA may also provide an advantage over CACS in identifying potential precursor lesions of the acute coronary syndrome (ACS), so-called vulnerable plaque [4]. In a cohort of symptomatic patients, Motoyama et al. [4] reported that the CT features of vulnerable plaque include positive remodeling and low attenuation plaque (\30 HU). ACS events were reported in only 0.49 % of patients lacking these features. In contrast, patients with plaques showing positive remodeling and/or low attenuation plaque had a very high hazard ratio of 22.8 for developing ACS compared with those lacking such plaques [4]. A more recently reported coronary CTA finding associated with risk is the so-called ‘‘napkin-ring sign’’, defined as plaque with low-attenuation center surrounded by a rim of higher attenuation. In one study comprising symptomatic and asymptomatic patients, the napkin-ring sign was an independent predictor of ACS, although the sign had a limited sensitivity of 41 % [5]. However, whether any of these findings that are associated with symptomatic patients can be generalized to an asymptomatic screening population is an open question. In addition, coronary CTA has other intrinsic limitations. It cannot reliably discriminate thin-cap fibroatheroma, an important feature of vulnerable plaque from thick-cap fibroatheroma because of limitations of spatial resolution [6]. CT density of a non-calcified plaque may also be altered by different kV settings or the degree of intracoronary enhancement after the contrast injection [7]. Thus, it is difficult to reliably differentiate lipid core from fibrous plaque based on the CT density itself. Other practical limitations to the use of screening coronary CTA instead of CACS include potentially increased radiation exposure, intravenous contrast use, and the concern that it will lead to increased unnecessary downstream testing. However, the gap between coronary CTA and CACS in terms of radiation exposure has been closed due to substantial progress in applying radiation sparing techniques [8, 9]. Thus, radiation S. M. Yoo Department of Diagnostic Radiology, CHA University Bundang Medical Center, Sungnam, South Korea

Background: Bronchoscopy with transbronchial needleaspiration (TBNA) is valuable to diagnose lesions in the mediastinumand lung, but conventional fluoroscopic guidance may be suboptimal. Wedescribe the use of CT fluoroscopy to provide real-time, transaxial, TBNA localization, thus facilitating biopsy. Methods: Patients were selected because of prior unsuccessful bronchoscopy oranticipated difficulty owing to small size or inaccessibility of thelesion. CT fluoroscopy consists of a spiral CT scanner adapted using arapid-reconstruction algorithm and hardware that permits real-timein-room imaging. The bronchoscope was inserted on the CT scanner, whichwas used to guide TBNA instruments into the target lesion. Results: Of 27 patients who underwent TBNA with CTfluoroscopic assistance, 15 had mediastinal nodes, and 12 had lungnodules or focal infiltrates. Mean lesion size was 1.7 cm in themediastinum, 2.2 cm in the lung. A correct diagnosis was established in10 of 12 mediastinal lesions (83%) for which follow-up was availableand in 8 lung lesions (67%). Diagnoses included small cell andnon-small cell lung cancer and invasive aspergillosis. False-negativeresults were caused by sampling errors or inability to reach the lesionas documented by CT fluoroscopy. Postprocedure CT fluoroscopy revealedno complications. Conclusion: CT fluoroscopy provideseffective, real-time guidance for TBNA and may be particularly valuablein patients with small or less accessible mediastinal or lunglesions.

In the past several years, CT fluoroscopy has proved a valuable new technique in guiding the performance of intrathoracic procedures. Several approaches to using CT fluoroscopy are discussed. We have found an interrupted, real-time technique optimal to facilitate biopsy of percutaneous lung nodules, particularly small lesions. The technique is also valuable in assisting thoracic drainage procedures. This article also discusses the use of CT fluoroscopy to guide transbronchial needle aspiration, which is another potentially important application.

Computed tomography of the chest is the present mainstay of cross-sectional imaging in patients with lung cancer. MR imaging, however, plays a complementary role in evaluating apical tumor and is often used as a problem-solving tool when CT findings are equivocal. New developments such as contrast-enhanced MR imaging and whole-body MR imaging may broaden the indications for this technique in the future.

We evaluated whether the use of multiple window and level settings on a soft-copy workstation improves diagnostic accuracy on chest and abdominal CT. We hypothesized that routinely using window and level settings during soft-copy interpretation would beneficially affect the final diagnosis without compromising efficiency.Two hundred three randomly selected abdominal and chest CT scans were interpreted by three radiologists using a four-monitor soft-copy workstation (images per screen, nine; resolution, 2K). After the initial interpretations, all scans were reevaluated by the same radiologists using additional liver and bone window and level settings. Differences in conspicuity and characterization of abnormalities were graded on a three-point scale.Conspicuity and characterization of abnormalities were improved in 67% of abnormal findings (81/121; p = 0.01). Improvement (a finding that substantially affected the final diagnosis) was present in 18% of abnormal findings (22/121; p = 0.04). On average, the evaluation of images at multiple window and level settings required an additional 40 sec per case.The use of multiple window and level settings during soft-copy interpretation resulted in improved lesion detectability and characterization with greater diagnostic efficacy. Using soft-copy workstations, radiologists can evaluate images using multiple settings without compromising efficiency.

Essential to any business, quality improvement typically requires stringent selection and training procedures for newly hired employees. But strengthening an organization's selection criteria can leave a firm open to charges of disparate impact and discrimination. In this article, the authors discuss the conflict between quality improvement and equal opportunity efforts, and offer strategies for helping organizations meet both their quality improvement goals and their equal opportunity responsibilities.

Study objective: The presence of pleural adhesions may render video-assisted thoracoscopic surgery (VATS) difficult or impossible. The aim of this study was to assess the value of chest CT in the detection of pleural adhesions prior to VATS. Design: Prospective study of the accuracy of chest CT in detecting pleural adhesions prior to VATS. Setting: Tertiary-referral teaching hospital and Veterans Administration hospital. Patients: Between July 1994 and March 1995, 63 consecutive patients undergoing 64 VATS procedures were evaluated with chest CT prior to surgery. Measurements and results: Preoperative scans were interpreted by consensus of two pulmonary radiologists prior to surgery. Suspected pleural adhesions and other findings related to the pleura were recorded on a form given to the surgeon prior to VATS. The surgeon confirmed or excluded each suspected adhesion during VATS, and documented any other lesions not identified preoperatively. Patient-by-patient and lesion-by-lesion analyses were performed. Pleural adhesions were correctly identified by CT in 28 of 39 cases (sensitivity, 71%) and excluded in 18 of 25 cases (specificity, 72%). On a lesion-by-lesion basis, 73 adhesions were identified during VATS, of which only 28 were identified prospectively at CT. There were 45 missed adhesions and 20 adhesions that were suggested falsely (sensitivity, 38%; specificity, 46%). Eighteen pleural spaces were correctly identified as being free of pleural adhesions. Conclusions: CT is moderately sensitive and specific for preoperative identification of pleural adhesions in patients undergoing VATS but its accuracy is poorer for individual lesions. (CHEST 1999; 115:423‐ 427)

The relationships among mastery and frequency of managerial behaviors, and subunit effectiveness have frequently been confused. This study investigates both main and interactive effects. The results show that the interaction effect can often be the strongest effect and that increasing frequency without improving mastery can sometimes be detrimental. Furthermore, these results offer a possible explanation as to why research of managerial behavior has been so inconclusive. In addition, the results question popular advice given often to managers. Finally, some recommendations are made as to how management development could be made more effective based on the results of this study.

Missed lung cancer is an important medicolegal issue and is the second leading cause for malpractice actions against radiologists. Contributing factors to overlooked lung cancer can be ascribed to observer performance, lesion characteristics, and technical considerations. Of these, errors related to observer performance are probably the most important. Missed lung cancer does not necessarily constitute malpractice, but lesions of high conspicuity are more likely to be associated with an adverse legal outcome. Multiple strategies have been advocated to reduce the frequency of missed lung cancer. Several studies have emphasized the importance of careful comparison of the current radiograph with one or more prior examinations.

The article examines the pros and cons of team teaching. Three models of team teaching are compared. The interactive model puts two or more teachers in front of the class at the same time. Both teachers comment on most of the topics being discussed. The rotational model places each member of the team in only that part of the course related to his or her area of expertise. In the Participant-Observer model, each team member alternatively leads instruction. The other team member participates by adding comments to the presentation. No single method is found to be best in all cases.

Cartilaginous disorders of the thorax can arise in the parenchyma, airways, chest wall, and axial skeleton. At radiography, pulmonary hamartoma is characterized by "popcorn" calcification or fat density, either of which is diagnostic. Bronchiectasis is best demonstrated at high-resolution computed tomography (CT) and has a "tramline" or "signet ring" appearance. Tracheopathia osteochondroplastica appears at CT as multiple sessile submucosal nodules with or without calcification along the cartilaginous portion of the trachea. In relapsing polychondritis, the trachea and mainstem bronchi have diffuse or focal thickening with luminal narrowing at radiography. Costochondritis of the chest wall has become more prevalent with increased intravenous drug abuse and may be demonstrated at CT as soft-tissue swelling along with underlying cartilaginous fragmentation and bone destruction. Enchondromas are expansile and may display a calcified cartilaginous matrix at radiography. In osteochondroma, the thickness of the cartilaginous cap determines the likelihood of malignant degeneration. At radiography, chondroblastomas have a round contour, sharp margins, and cortical scalloping, whereas chondrosarcomas are large masses with indistinct margins, cortical breakthrough, and soft-tissue extension. By identifying either a process affecting a cartilage-containing structure or a cartilaginous matrix within a lesion, the chest radiologist may be able to narrow the list of differential diagnostic possibilities substantially.

The authors present their experience with previously unsuspected carcinoma of the lung detected at preoperative computed tomography (CT) in patients with severe pulmonary emphysema who were scheduled to undergo lung volume reduction surgery.Preoperative chest CT was performed in 148 patients (84 men, 64 women; mean age, 65 years +/- 8 [standard deviation]) with advanced pulmonary emphysema before lung volume reduction surgery. At surgery, an attempt was made to excise any pulmonary nodule considered suspicious for carcinoma at CT.Eighteen pulmonary nodules suspicious for lung cancer were found at CT in 17 (11%) of the 148 patients. Sixteen of these 148 nodules were resected at lung volume reduction surgery. Nine non-small cell carcinomas (adenocarcinoma, n = 4, including three with bronchioloalveolar differentiation; poorly differentiated, n = 3; squamous cell carcinoma, n = 2) were found in eight (5%) patients. Eight of the cancers were stage I, and one was unstaged surgically. Maximum diameters of the cancers ranged between 1.0 and 3.8 cm (median, 1.6 cm). The seven (5%) other resected nodules were all benign.A 5% rate of stage I primary lung cancer in patients selected for lung volume reduction surgery suggests that performance of chest CT in candidates for lung volume reduction surgery is appropriate not only to identify patterns of pulmonary parenchymal destruction but also to search for stage I lung cancer.

Background Although the fine needle aspiration biopsy (FNAB) technique is widely applied to thoracic and soft tissue tumors, the cytologic morphology of solitary fibrous tumors is not fully established. Cases We report the cytologic features observed on computed tomography (CT)-guided FNAB obtained from two benign solitary fibrous tumors of the pleura in two males. The cytologic findings were compared to the light and electron microscopic features. The smears were composed of spindle cells dispersed amid a delicate network of small blood vessels. scattered among these spindle cells were also epithelioid cells arranged singly or in small clusters. These cells were polygonal, with moderately dense, homogeneous or finely vacuolated, basophilic cytoplasm and a moderately high nuclear/cytoplasmic ratio. The nuclei were oval to round and slightly hyperchromatic and rarely had small nucleoli. Abundant spindle-shaped, round, naked nuclei were seen in the background. Stains for CD34 were positive in the epithelioid and spindle cells. Histologically the lesions were composed of spindle cells embedded in a collagenous matrix. Hypercellular nodules and focal hemangiopericytic and storiform patterns were also observed. There were no features suggesting malignancy. In electron microscopic evaluation there were fibroblastic cells in a collagenous matrix as well as polygonal cells singly and in clusters with scanty to moderate amounts of cytoplasm containing sparse organelles. The cells were attached to each other by tight junctions. Occasionally, cells were surrounded by short segments of basal lamina. Conclusion The cytomorphologic pattern described above correlates well with the histologic and ultrastructural findings in benign solitary fibrous tumors (SFT) and corresponds perfectly to the histogenetic concept of this lesion. As with other tumors, fine needle aspiration biopsy is helpful in the evaluation of SFT.

As an important tool for diagnosing acute coronary syndrome and stable angina, coronary CT angiography has been increasingly being performed in patients presenting with atypical chest pain. In order to help treating patients more efficiently, it is crucial for radiologists to have a comprehensive understanding about mechanisms and clinical aspects as well as CT findings of coronary atherosclerosis per se. A thorough understanding and optimal performance of coronary CT angiography may lead to reduction of unjustified downstream testing. This article provides a clinical and radiological overview of coronary atherosclerosis, and a practical guideline about how to interpret degree of stenosis on coronary CT angiography.

Purpose Our goal was to determine the prevalence of intrathoracic lymphadenopathy on chest CT in patients with empyema. Method We retrospectively identified 27 patients (14 men, 13 women, mean age 43 years) with nontuberculous empyema examined with chest CT. All scans were reviewed by two of three board-certified radiologists for the presence of intrathoracic lymphadenopathy (> or = 1 cm, short axis) in an American Thoracic Society (ATS) nodal station or the internal mammary region. Differences were resolved by consensus. Results Thirteen (48%) patients with empyema had lymphadenopathy on chest CT. The mean number of enlarged lymph nodes for the patients with lymphadenopathy was 3.2 (SD +/-2.3, range 1-8). The mean size of the largest lymph node was 1.4 cm (range 1.0-2.5 cm). The lymphadenopathy was unilateral and ipsilateral to the empyema in seven (54%), bilateral in five (38%), and unilateral contralateral to the empyema in one. The distribution of lymphadenopathy according to ATS nodal stations was 4R (n = 8), 7 (n = 6), 10R (n = 5); n = 2 each 2R, 10L, 11L; and n = 1 each 11R, 2L, 4L, and 6. Four patients had internal mammary lymphadenopathy. Pleural fluid and smooth pleural thickening were present in each case. Four patients had follow-up CT after treatment. There was a decrease or resolution of the lymphadenopathy in each case. Conclusion Intrathoracic lymphadenopathy is a common CT finding in patients with empyema and occurred in 48% of this series. In patients with smooth pleural thickening and pleural effusion, intrathoracic lymphadenopathy should not be used as a criterion to differentiate empyema from malignant or tuberculous pleural effusion.

The elementary classroom is the locus of vigorous debate about how schools should foster the development of civic virtue, which the Founders believed was essential to sustain a democratic republic. Two general approaches to moral development are vying for support. One focuses on forming moral habits; the other, on developing moral reasoning. The article describes each approach and summarizes the critiques of its opponents. The author recommends the use of both approaches in elementary schools, with an early emphasis on habit formation and a gradual increase in attention to moral reasoning.

Successful organizations recognize that employees are their most valuable resource because of employee commitment to the organization. Organizational commitment is a multi‐dimensional variable which is the degree of loyalty to one's job and organization. Employers should strive to increase organizational commitment of employees. One suggested method is employer educational assistance.

The purpose of this study is to assess the use of a pulmonary embolism (PE)- computer-aided detection (CADx) program in the detection of PE missed in clinical practice.Pulmonary CT angiography (CTA) studies (n = 6769) performed between January 2009 and July 2012 were retrospectively assessed by a thoracic radiologist. In studies that were positive for PE, all prior contrast-enhanced pulmonary CTA studies were reviewed. Missed PE was deemed to have occurred if PE was not described in the final interpretation. The presence, proximal extent, and number of PEs were agreed on by three thoracic radiologists. Studies with missed acute PE and available slice thickness of 2 mm or less were assessed with a prototype PE-CADx program. False-positive PE-CADx marks were analyzed. Outcomes of missed acute PEs were assessed in patients with both follow-up imaging and clinical data.Fifty-three studies with overlooked acute PE met our inclusion criteria for PE-CADx assessment. The PE-CADx program identified at least one PE in 77.4% of instances (41/53). PE-CADx correctly marked at least one PE in 23 of 23 cases (100%) with multiple PEs and 18 of 30 (60%) cases with a solitary PE (p0.001). PE-CADx per-study sensitivity was significantly higher for segmental (65.5%) than for subsegmental (91.7%) PEs (p = 0.002). PE-CADx averaged 3.8 false-positive marks per case (range, 0-23 marks). Fourteen patients with missed PE who were not receiving anticoagulation therapy developed new PEs, including nine with an isolated subsegmental PE on the initial CT scan.PE-CADx correctly identified 77.4% of cases of acute PE that were previously missed in clinical practice.

Purpose The aim of this study was to assess the feasibility and image quality of a low-dose triple-rule-out (TRO) computed tomography (CT) angiogram on a second-generation dual-source CT scanner using a high-pitch helical acquisition. Materials and methods Ten men (mean age 56.3 y, average body mass index 24.2) underwent TRO CT angiography using a high-pitch helical acquisition. Patients were imaged from the lung bases to the thoracic inlet in a caudocranial direction. A biphasic injection was administered at 6 mL/s. Study parameters including kVp, mAs, CT dose index volume, dose-length product, and effective dose were calculated. Image quality was independently assessed by 2 cardiothoracic radiologists using the following scale: 1-nondiagnostic; 2-moderately limited diagnostic ability; 3-mild limitation but diagnostic; 4-ideal. For each patient up to 23 structures were evaluated: 17 coronary segments, 3 pulmonary artery levels, 2 aortic sections, and the lung parenchyma. The unpaired t test and the Fisher exact test were used for comparison between patients scored at 80 and 100 kV. Results The average CT dose index volume, dose-length product, and effective dose for the TRO scans was 2.65, 81.9, and 1.39 mSv, respectively. Readers 1 and 2 scored 171/203 (83%) and 173/203 (84%) of the evaluated regions as ideal and 26/203 (12.8%) and 24/203 (11.8%) as being mildly limited, respectively. Each reader graded 6/203 (3.9%) as being moderately limited. No areas were nondiagnostic. Patients scanned at 80 kV had a significantly higher number of limited segments for readers 1 (P=0.0012) and 2 (P=0.0027). Conclusions Low-dose, high-image quality TRO scans can be effectively performed using a high-pitch helical acquisition.

Genetic loci for body mass index (BMI) in adolescence and young adulthood, a period of high risk for weight gain, are understudied, yet may yield important insight into the etiology of obesity and early intervention. To identify novel genetic loci and examine the influence of known loci on BMI during this critical time period in late adolescence and early adulthood, we performed a two-stage meta-analysis using 14 genome-wide association studies in populations of European ancestry with data on BMI between ages 16 and 25 in up to 29 880 individuals. We identified seven independent loci (P < 5.0 × 10⁻⁸) near FTO (P = 3.72 × 10⁻²³), TMEM18 (P = 3.24 × 10⁻¹⁷), MC4R (P = 4.41 × 10⁻¹⁷), TNNI3K (P = 4.32 × 10⁻¹¹), SEC16B (P = 6.24 × 10⁻⁹), GNPDA2 (P = 1.11 × 10⁻⁸) and POMC (P = 4.94 × 10⁻⁸) as well as a potential secondary signal at the POMC locus (rs2118404, P = 2.4 × 10⁻⁵ after conditioning on the established single-nucleotide polymorphism at this locus) in adolescents and young adults. To evaluate the impact of the established genetic loci on BMI at these young ages, we examined differences between the effect sizes of 32 published BMI loci in European adult populations (aged 18-90) and those observed in our adolescent and young adult meta-analysis. Four loci (near PRKD1, TNNI3K, SEC16B and CADM2) had larger effects and one locus (near SH2B1) had a smaller effect on BMI during adolescence and young adulthood compared with older adults (P < 0.05). These results suggest that genetic loci for BMI can vary in their effects across the life course, underlying the importance of evaluating BMI at different ages.

To better understand the natural history, management, and outcome of pneumothoraces in HIV-infected patients, we reviewed hospital charts and chest radiographs of HIV-infected adults discharged from the University of Maryland Medical Center over a 6-year period. Sixty pneumothoraces occurred in 39 patients. Twenty-three pneumothoraces resulted from trauma and 37 were spontaneous. Thirty-two (86%) of the spontaneous pneumothoraces occurred in patients with Pneumocystis carinii pneumonia (PCP). Eight percent of the traumatic pneumothoraces in patients who did not have PCP resolved. Patients who had pneumothorax as well as PCP were more difficult to manage and had a poorer outcome (50% mortality) than those who did not have PCP (25% mortality).

To review the literature and the authors' experience with admission contrast material-enhanced computed tomography (CT) in patients admitted after blunt trauma.From January 1990 to December 1994, thoracic CT was performed to evaluate traumatic aortic injury in 677 patients with positive or equivocal findings at chest radiography. CT scans positive for mediastinal hemorrhage or aortic injury were retrospectively reviewed and interpreted by consensus, with angiographic and surgical confirmation.CT findings were negative for TAI in 570 (84%) of the 677 patients. Mediastinal hemorrhage was reported in 100 patients and was the only abnormality in 79 of them. Findings at angiography were negative for traumatic aortic injury in 77 (97%). CT signs of traumatic aortic injury in 21 patients included contour abnormality or pseudoaneurysm (n = 19), intimal flap(s) (n = 8), and pseudocoarctation (n = 3). Findings at angiography were positive for traumatic aortic injury in 19 (90%). For aortic injury and mediastinal hemorrhage, respectively, specificity for traumatic aortic injury was 99% and 87% and sensitivity was 90% and 100%; at meta-analysis of data from the authors and the literature, sensitivity was 97.0% and 99.3% and specificity was 99.8% and 87.1%. Reliance on findings at admission CT rather than radiography to indicate suspicion for traumatic aortic injury before angiography resulted in savings of more than $365,000.The CT finding of mediastinal hemorrhage alone is sensitive for traumatic aortic injury, but the finding of aortic injury is more specific.

The pericardium and cardiac malignancies are well visualized on MR imaging because of the superb contrast resolution and multiplanar capability of the technique. This article highlights some of the clinical uses of MR imaging in evaluating the pericardium and cardiac lesions and provides comparison with echocardiography and CT scan. Specific diseases that are described include pericardial effusion, constrictive pericarditis, neoplastic pericardial disease, congenital abnormalities of the pericardium, benign, malignant and metastatic cardiac tumors, and paracardiac masses. This article discusses the impact of newer MR techniques such as cine MR imaging on the assessment of pericardial disease and cardiac lesions.

PURPOSE: To describe the appearances of overlooked lung cancer at computed tomographic (CT) examination and to analyze the reasons for failure to diagnose these lesions. MATERIALS AND METHODS: Fourteen patients with 15 overlooked lung cancers were identified by radiologists at three institutions. Location, shape, and cell type of each cancer were reviewed, and other relevant findings of CT examinations were assessed. RESULTS: The missed tumors manifested as endobronchial lesion (n = 10), solitary parenchymal nodule (n = 2), area of focal peripheral air-space disease (n = 2), or pleural-based thickening (n = 1). Eleven (73%) of the 15 lesions were located in a lower lobe. In six (43%) of 14 patients, major distracting findings were present elsewhere in the thorax. CONCLUSION: Endobronchial location and lower lobe predominance were the most common characteristics of overlooked lung cancer at CT. The presence of unrelated major abnormalities at CT may also have contributed to failure to diagnose the tumor.

Poster: "ECR 2018 / C-0136 / Current concepts of vulnerable plaque on coronary CT angiography" by: "S. M. Yoo; Bundang/KR"

Diversity has increasingly become a “hot‐button” issue in corporate, political, and legal arenas. While many organizations have embraced diversity, others still consider it merely an issue of compliance with legal requirements. Effective diversity management has historically been used to provide a legally defensive position; that is, a firm with a diverse workforce could argue that they were not guilty of discrimination because of the prima facie case based on their workforce demographics representing the demographics of the local community. However, in more recent years, the view of diversity has dramatically changed to a more proactive concept.

The use of axisymmetric tensile creep specimens containing semicircular notches is shown to provide important data which complement results of the common smooth tensile creep test. The notch provides a stress and strain concentration which can represent the non-uniform state of actual components in service. Finite element analysis confirms that the initial concentration of stress redistributes during creep to yield a more uniformly loaded cross-section. Additionally, it is shown that the stress follows a highly non-proportional loading path during creep. The first experiments of notched tensile creep of a ceramic (silicon nitride) are examined in the light of finite element simulations of the transient deformation. The implications of notched tensile creep are discussed as an important test for the evaluation of constitutive models.

The intent of CAD-RADS - Coronary Artery Disease Reporting and Data System is to create a standardized method to communicate findings of coronary CT angiography (coronary CTA) in order to facilitate decision-making regarding further patient management. The suggested CAD-RADS classification is applied on a per-patient basis and represents the highest-grade coronary artery lesion documented by coronary CTA. It ranges from CAD-RADS 0 (Zero) for the complete absence of stenosis and plaque to CAD-RADS 5 for the presence of at least one totally occluded coronary artery and should always be interpreted in conjunction with the impression found in the report. Specific recommendations are provided for further management of patients with stable or acute chest pain based on the CAD-RADS classification. The main goal of CAD-RADS is to standardize reporting of coronary CTA results and to facilitate communication of test results to referring physicians along with suggestions for subsequent patient management. In addition, CAD-RADS will provide a framework of standardization that may benefit education, research, peer-review and quality assurance with the potential to ultimately result in improved quality of care.

A study was undertaken to evaluate the safety and efficacy of thoracoscopic lung biopsy for interstitial lung disease. The relation between operative findings, pathologic findings, and preoperative computed tomographic scan findings was examined. Twenty-six patients, 10 male and 16 female, underwent thoracoscopic lung resection to diagnose interstitial lung disease. Sixteen patients were outpatients for an elective procedure; 10 were inpatients including 2 who were ventilator dependent. The mean length of operation was 54 minutes and the mean length of chest tube duration, 1.3 days. There were no deaths. Staphylococcal pneumonia developed in 1 patient postoperatively. One patient with systemic pulmonary hypertension was ventilator dependent for 48 hours. A double-lumen endotracheal tube was used in all but 2 patients. Twelve-millimeter trocar ports were used to allow easy interchange of staplers and endoscopic instruments. Biopsy of at least two lobes was performed in each patient with resection of a piece of grossly abnormal lung. A single chest tube was left routinely. The pathologic diagnosis was usual interstitial pneumonitis in 7 patients. Four patients had interstitial fibrosis and 4, granulomas. Three patients had diffuse alveolar damage and 3, Wegener's granulomatosis. Two patients had bronchiolitis obliterans with organizing pneumonia. One patient each had lymphangioleiomyomatosis, eosinophilic granuloma, and cytomegalovirus. Sixteen patients underwent preoperative computed tomographic scanning. The scans were assessed by 2 radiologists who were blinded to the surgical results. Computed tomography accurately predicted the site of disease in most instances. Four patients had at least one lobe with no evidence of disease on computed tomography but with interstitial lung disease found at thoracoscopy. One of these patients had no evidence of disease on computed tomographic scans. Thoracoscopy allows selective biopsy of multiple lung segments, thereby increasing the diagnostic yield in interstitial lung disease.

Aortic valve calcification that is visualized on chest radiographs is considered a marker for clinically significant aortic stenosis, but the clinical importance of this finding on CT is unknown. Accordingly, we studied the prevalence and clinical relevance of aortic valve calcification found incidentally on CT scans of the chest.After comparing computer records of chest CTs and echocardiograms, we identified 109 patients who underwent both studies during a 2-year period. Two thoracic radiologists reviewed the CT scans to identify and quantify aortic valve calcification. The quantity of aortic valve calcification was graded on a scale of 1 to 3, with grade 3 indicating the most severe calcification. The prevalence of calcification was correlated with patient age and sex. The findings on CT were correlated with hemodynamic data from echocardiography. At echocardiography, a peak aortic valve gradient of greater than 25 mm Hg was defined as abnormal.Aortic valve calcification was noted on CT scans in 33 (30%) of the 109 patients. Aortic valve calcification shown by CT was significantly more common in patients more than 65 years old (p.01). Five (15%) of 33 patients with aortic valve calcification shown by CT had abnormal aortic valve gradients at echocardiography. In contrast, none of 76 patients without aortic valve calcification shown by CT had abnormal aortic valve gradients (p.01). All five patients with abnormal aortic valve gradients had moderate quantities of aortic valve calcification seen on CT scans. Two of the five were younger than 55 years old.Aortic valve calcification is a common finding on CT scans and is usually clinically insignificant. Nevertheless, some patients with aortic valve calcification on CT have aortic stenosis, particularly those younger than 55 years old and those with moderately dense aortic valve calcification shown by CT. These patients may benefit from hemodynamic assessment of the aortic valve by echocardiography.

The integrity of silicone-gel breast implants can be evaluated by MR imaging. The findings of intra- and extracapsular rupture have been described. Increasingly sophisticated breast reconstruction techniques such as stacking of prostheses have lead to a wider range of implant appearances. We report a case where intracapsular rupture was simulated by slippage of two retropectoral stacked implants in relation to each other. The MR and CT findings are described.

The objective of our study was to evaluate the impact of computer-aided detection (CAD) on the identification of subsolid and solid lung nodules on thin- and thick-section CT.For 46 chest CT examinations with ground-glass opacity (GGO) nodules, CAD marks computed using thin data were evaluated in two phases. First, four chest radiologists reviewed thin sections (reader(thin)) for nodules and subsequently CAD marks (reader(thin) + CAD(thin)). After 4 months, the same cases were reviewed on thick sections (reader(thick)) and subsequently with CAD marks (reader(thick) + CAD(thick)). Sensitivities were evaluated. Additionally, reader(thick) sensitivity with assessment of CAD marks on thin sections was estimated (reader(thick) + CAD(thin)).For 155 nodules (mean, 5.5 mm; range, 4.0-27.5 mm)-74 solid nodules, 22 part-solid (part-solid nodules), and 59 GGO nodules-CAD stand-alone sensitivity was 80%, 95%, and 71%, respectively, with three false-positives on average (0-12) per CT study. Reader(thin) + CAD(thin) sensitivities were higher than reader(thin) for solid nodules (82% vs 57%, p0.001), part-solid nodules (97% vs 81%, p = 0.0027), and GGO nodules (82% vs 69%, p0.001) for all readers (p0.001). Respective sensitivities for reader(thick), reader(thick) + CAD(thick), reader(thick) + CAD(thin) were 40%, 58% (p0.001), and 77% (p0.001) for solid nodules; 72%, 73% (p = 0.322), and 94% (p0.001) for part-solid nodules; and 53%, 58% (p = 0.008), and 79% (p0.001) for GGO nodules. For reader(thin), false-positives increased from 0.64 per case to 0.90 with CAD(thin) (p0.001) but not for reader(thick); false-positive rates were 1.17, 1.19, and 1.26 per case for reader(thick), reader(thick) + CAD(thick), and reader(thick) + CAD(thin), respectively.Detection of GGO nodules and solid nodules is significantly improved with CAD. When interpretation is performed on thick sections, the benefit is greater when CAD marks are reviewed on thin rather than thick sections.

OBJECTIVE. Cardiovascular complications in patients with HIV infection include myocardial, endocardial, pericardial, and vascular diseases. The complications are caused by the HIV infection itself, opportunistic infections, HIV-related tumors, and the side effects of highly active antiretroviral therapy. The article reviews the CT and MRI findings suggestive of HIV-related cardiovascular diseases. CONCLUSION. The cardiovascular complications of HIV infection frequently overlap, making the diagnosis difficult. CT and MRI are useful for the noninvasive evaluation of these complications.

Mammography is the preferred technique to evaluate the breast but computed tomography (CT) performed for extramammary disease often images breast tissue. We reviewed studies of patients who underwent both CT and mammography to identify abnormalities that were visible with both techniques. The CT appearance of the normal breast, breast cancer, and several other abnormalities is demonstrated in this study. CT may occasionally allow for a precise diagnosis of a previously unsuspected breast lesion but a mammogram is usually required.