ALT-803, an IL-15 superagonist, in combination with nivolumab in patients with metastatic non-small cell lung cancer: a non-randomised, open-label, phase 1b trial.

BACKGROUND: Immunotherapy with PD-1 or PD-L1 blockade fails to induce a response in about 80% of patients with unselected non-small cell lung cancer (NSCLC), and many of those who do initially respond then develop resistance to treatment. Agonists that target the shared interleukin-2 (IL-2) and IL-15Rßγ pathway have induced complete and durable responses in some cancers, but no studies have been done to assess the safety or efficacy of these agonists in combination with anti-PD-1 immunotherapy. We aimed to define the safety, tolerability, and activity of this drug combination in patients with NSCLC. METHODS: In this non-randomised, open-label, phase 1b trial, we enrolled patients (aged ≥18 years) with previously treated histologically or cytologically confirmed stage IIIB or IV NSCLC from three academic hospitals in the USA. Key eligibility criteria included measurable disease, eligibility to receive anti-PD-1 immunotherapy, and an Eastern Cooperative Oncology Group performance status of 0 or 1. Patients received the anti-PD-1 monoclonal antibody nivolumab intravenously at 3 mg/kg (then 240 mg when US Food and Drug Administration [FDA]-approved dosing changed) every 14 days (either as new treatment or continued treatment at the time of disease progression) and the IL-15 superagonist ALT-803 subcutaneously once per week on weeks 1-5 of four 6-week cycles for 6 months. ALT-803 was administered at one of four escalating dose concentrations: 6, 10, 15, or 20 µg/kg. The primary endpoint was to define safety and tolerability and to establish a recommended phase 2 dose of ALT-803 in combination with nivolumab. Analyses were per-protocol and included any patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, number NCT02523469; phase 2 enrolment of patients is ongoing. FINDINGS: Between Jan 18, 2016, and June 28, 2017, 23 patients were enrolled and 21 were treated at four dose levels of ALT-803 in combination with nivolumab. Two patients did not receive treatment because of the development of inter-current illness during enrolment, one patient due to leucopenia and one patient due to pulmonary dysfunction. No dose-limiting toxicities were recorded and the maximum tolerated dose was not reached. The most common adverse events were injection-site reactions (in 19 [90%] of 21 patients) and flu-like symptoms (15 [71%]). The most common grade 3 adverse events, occurring in two patients each, were lymphocytopenia and fatigue. A grade 3 myocardial infarction occurred in one patient. No grade 4 or 5 adverse events were recorded. The recommended phase 2 dose of ALT-803 is 20 µg/kg given once per week subcutaneously in combination with 240 mg intravenous nivolumab every 2 weeks. INTERPRETATION: ALT-803 in combination with nivolumab can be safely administered in an outpatient setting. The promising clinical activity observed with the addition of ALT-803 to the regimen of patients with PD-1 monoclonal antibody relapsed and refractory disease shows evidence of anti-tumour activity for a new class of agents in NSCLC. FUNDING: Altor BioScience (a NantWorks company), National Institutes of Health, and Medical University of South Carolina Hollings Cancer Center.

Pretreatment 18F-Fluorodeoxyglucose Positron Emission Tomography Standardized Uptake Values and Tumor Size in Medically Inoperable Nonsmall Cell Lung Cancer Is Prognostic of Overall 2-Year Survival After Stereotactic Body Radiation Therapy.

OBJECTIVE: The aim of this study was to determine prognostic value of tumor size and metabolic activity on survival for patients with early stage nonsmall cell lung cancer receiving stereotactic body radiation therapy. METHODS: We retrospectively evaluated the patients who underwent positron emission tomography-computed tomography scan before stereotactic body radiation therapy treatment. Tumor diameter, tumor volume, maximum standardized uptake value (SUVmax), standardized uptake value (SUV) average, and SUV volume were obtained. Cox regression analyses were performed to determine the associations between tumor characteristics and survival. RESULTS: The patients with large tumors and high SUVmax have worse survival than patients with small tumors and low SUVmax (hazard ratio [HR] = 3.47, P = 0.007). Patients with small tumors and high SUVmax (HR = 1.80; P = 0.24) and large tumors and low SUVmax (HR = 1.55; P = 0.43) had increased risk of death compared with patients with small tumors and low SUVmax. CONCLUSIONS: Both increased tumor size and metabolic activity are associated with increased risk of death. Combining size and metabolic activity together is superior for predicting 2-year survival and identifying patients for whom survival is statistically worse.

The accuracy of pleural ultrasonography in diagnosing complicated parapneumonic pleural effusions.

We compared the accuracy of pleural ultrasound versus chest CT versus chest radiograph (CXR) to determine radiographic complexity in predicting a complicated parapneumonic effusion (CPPE) defined by pleural fluid analysis. 66 patients with parapneumonic effusions were identified with complete data. Pleural ultrasound had a sensitivity of 69.2% (95% CI 48.2% to 85.7%) and specificity of 90.0% (95% CI 76.3% to 97.2%). Chest CT had a sensitivity of 76.9% (95% CI 56.3% to 91.0%) and specificity of 65.0% (95% CI 48.3% to 79.4%). CXR had a sensitivity of 61.5% (95% CI 40.6% to 79.8%) and specificity of 60.0% (95% CI 43.3% to 75.1%). Pleural ultrasound appears to be a superior modality to rule in a CPPE when compared with chest CT and CXR.

Association of Coronary Artery Calcification and Mortality in the National Lung Screening Trial: A Comparison of Three Scoring Methods.

PURPOSE: To evaluate three coronary artery calcification (CAC) scoring methods to assess risk of coronary heart disease (CHD) death and all-cause mortality in National Lung Screening Trial (NLST) participants across levels of CAC scores. MATERIALS AND METHODS: The NLST was approved by the institutional review board at each participating institution, and informed consent was obtained from all participants. Image review was HIPAA compliant. Five cardiothoracic radiologists evaluated 1575 low-dose computed tomographic (CT) scans from three groups: 210 CHD deaths, 315 deaths not from CHD, and 1050 participants who were alive at conclusion of the trial. Radiologists used three scoring methods: overall visual assessment, segmented vessel-specific scoring, and Agatston scoring. Weighted Cox proportional hazards models were fit to evaluate the association between scoring methods and outcomes. RESULTS: In multivariate analysis of time to CHD death, Agatston scores of 1-100, 101-1000, and greater than 1000 (reference category 0) were associated with hazard ratios of 1.27 (95% confidence interval: 0.69, 2.53), 3.57 (95% confidence interval: 2.14, 7.48), and 6.63 (95% confidence interval: 3.57, 14.97), respectively; hazard ratios for summed segmented vessel-specific scores of 1-5, 6-11, and 12-30 (reference category 0) were 1.72 (95% confidence interval: 1.05, 3.34), 5.11 (95% confidence interval: 2.92, 10.94), and 6.10 (95% confidence interval: 3.19, 14.05), respectively; and hazard ratios for overall visual assessment of mild, moderate, or heavy (reference category none) were 2.09 (95% confidence interval: 1.30, 4.16), 3.86 (95% confidence interval: 2.02, 8.20), and 6.95 (95% confidence interval: 3.73, 15.67), respectively. CONCLUSION: By using low-dose CT performed for lung cancer screening in older, heavy smokers, a simple visual assessment of CAC can be generated for risk assessment of CHD death and all-cause mortality, which is comparable to Agatston scoring and strongly associated with outcome.

Computed tomography of acute pulmonary embolism: state-of-the-art.

Multidetector computed tomography (CT) plays an important role in the detection, risk stratification and prognosis evaluation of acute pulmonary embolism. This review will discuss the technical improvements for imaging peripheral pulmonary arteries, the methods of assessing pulmonary embolism severity based on CT findings, a multidetector CT technique for pulmonary embolism detection, and lastly, how to avoid overutilization of CT pulmonary angiography and overdiagnosis of pulmonary embolism. Key Points • We describe clinical prediction rules and D-dimers for pulmonary embolism evaluation. • Overutilization of CT pulmonary angiography and overdiagnosis of pulmonary embolism should be avoided. • We discuss technical improvements for imaging peripheral pulmonary arteries. • Pulmonary embolism severity can be assessed based on CT findings. • We discuss multidetector CT techniques for pulmonary embolism detection.

Integrated cardiothoracic imaging with computed tomography.

The respiratory and the cardiovascular systems are intimately connected. Because of the high degree of morphological and functional interaction, pathophysiological processes in one compartment are likely to induce adaptive changes in the other. Computed tomography (CT) plays a central role in the diagnostic work up of both thoracic and cardiac disorders. Historically, these two systems have been evaluated separately; however, CT technology has evolved remarkably over recent decades. Up-to-date advanced imaging strategies allow for a combined assessment of the cardiopulmonary unit. Besides improved techniques of electrocardiogram (ECG)-synchronization for obtaining both morphological and functional information, latest advances of dual-source CT (DSCT) have shown great promise for even more comprehensive integrated cardiothoracic imaging.

Relationship of main pulmonary artery diameter to pulmonary arterial pressure in scleroderma patients with and without interstitial fibrosis.

OBJECTIVE: This study aimed to determine the relationship between main pulmonary artery diameter (MPAD) and pulmonary hypertension (PH) in scleroderma patients with and without interstitial lung disease. METHODS: We retrospectively reviewed 48 subjects with scleroderma who underwent a chest computed tomography (CT) and right heart catheterization with 6 months of each other. Patients were divided into 2 groups based on the absence or presence of interstitial lung disease on chest CT. Subset analysis was performed based on available pulmonary function tests and divided into groups by forced vital capacity (FVC). Computed tomographic scans were scored for extent of fibrosis and ground glass opacity. Pulmonary artery and ascending aorta measurements were obtained by 2 independent observers. Univariate and multivariate models were used to evaluate the correlation between MPAD and mean pulmonary artery pressure (mPAP) measured by right heart catheterization. Receiver operating characteristic analysis was performed for diagnostic accuracy of the MPAD measurement in predicting PH. RESULTS: Strong correlations between mPAP and MPAD were found in this study regardless of the presence or absence of mild to moderate interstitial fibrosis on chest CT. When dividing patients based on FVC, the correlation between mPAP and MPAD was substantially attenuated. An MPAD value of 30.8 mm yielded the highest sensitivity and specificity at 81.3% and 87.5%, respectively. CONCLUSIONS: In scleroderma patients, an enlarged main pulmonary artery (>30 mm) predicts PH even in the presence of mild to moderate fibrosis although the relationship may be attenuated in the presence of a low % FVC.

Reproducibility of CT signs of right ventricular dysfunction in acute pulmonary embolism.

OBJECTIVE: The purpose of our study was to determine the interobserver reproducibility of CT findings of right ventricular (RV) dysfunction in pulmonary embolism (PE). MATERIALS AND METHODS: Two experienced observers independently and retrospectively evaluated pulmonary CT angiography (CTA) studies of 50 patients with acute PE for the following signs: bowing of the interventricular septum, inferior vena cava (IVC) contrast medium reflux, RV diameter (RVD)/left ventricular diameter (LVD) ratio on axial sections and four-chamber (4-CH) views, and RV volume (RVV)/left ventricular volume (LVV) ratio. Analysis used kappa statistics, Spearman's rank correlation, and Bland-Altman statistics. RESULTS: The two observers had fair to moderate agreement (kappa = 0.32-0.44) for septal bowing and moderate to good agreement (kappa = 0.57-0.68) for diagnosing IVC reflux. The Spearman's rank correlation coefficients for RVD(axial)/LVD(axial) ratio and RVD(4-CH)/LVD(4-CH) ratio between the two observers were 0.88 (p < 0.001) and 0.85 (p < 0.001), respectively. On Bland-Altman analysis, the mean differences for RVD(axial)/LVD(axial) ratio and RVD(4-CH)/LVD(4-CH) ratio were 0.014 (+/- 0.195) and 0.001 (+/- 0.242), respectively. The correlation coefficient for RVV/LVV ratio was 0.93 (p < 0.001), and the mean difference was 0.033 (+/- 0.229). CONCLUSION: Considerable differences exist in the interobserver reproducibility of CT findings of RV dysfunction on pulmonary CTA in patients with acute PE. Cardiac chamber measurements are more reproducible than septal bowing and IVC reflux. Volumetric determination of the RVV/LVV ratio is the least user dependent and most reproducible.

Congenital bronchial artery-pulmonary artery fistula in an adult.

We report the case of a 21-year-old man who presented with a hilar mass and whose condition was diagnosed as a congenital anomalous communication between the bronchial and pulmonary artery. We review his lung vascular embryology and anatomy that led to this rare systemic to pulmonary arterial shunt, describe other etiologies that may lead to abnormal systemic artery to pulmonary artery communication, and briefly discuss treatment options.

Extra-cardiac findings at cardiac CT: experience with 1,764 patients.

To investigate incidental extra-cardiac findings (ECF) at cardiac CT based on indication and impact on patient management. We retrospectively reviewed the reports of 1,764 patients who underwent a cardiac CT study between January 1, 2004 and December 31, 2006, including 463 calcium scorings (CS), 737 coronary CT angiograms (CTA), 341 pulmonary vein stenoses (PVS), and 223 bypass grafts (CABG). ECFs were categorized by type of examination, anatomical location and clinical significance. Comparisons were made between examination types to determine if incidental findings varied by indication. There were 507 ECFs with at least one ECF in 441 patients (25.0%). By examination, there was at least 1 ECF in 79/463 CS studies (17.1%), 196/737 CTAs (26.6%), 80/341 PVSs (23.4%) and 86/223 CABGs (38.6%). In 325 patients (18.4%), the findings were considered clinically important and occurred in 60/463 (12.9%) CSs, 149/737 (20.2%) CTAs, 56/341 (16.4%) PVSs and 60/223 (26.9%) CABGs. Differences between CABG and other indications and CTA vs. CS for incidental and clinically important findings were statistically significant (p < 0.05). Extra-cardiac findings requiring follow-up occur in 18% of patients and are significantly more frequent in coronary artery CTA and coronary artery bypass studies than in calcium scoring studies.

Negative predictive value of computed tomography pulmonary angiography with indirect computed tomography venography in intensive care unit patients.

PURPOSE: The aim of the study was to evaluate the negative predictive value (NPV) of combined computed tomography (CT) pulmonary angiography (CTPA) and indirect CT venography (CTV) in the intensive care unit (ICU) setting. MATERIALS AND METHODS: We retrospectively reviewed the records of 181 consecutive ICU patients who underwent CTPA/CTV. Radiology reports were examined to determine whether the study was positive for pulmonary embolism (PE), PE and deep venous thrombosis (DVT), or DVT alone; indeterminate; or negative. Results that were reported as negative were further evaluated for evidence of PE or DVT within 30 days by imaging, clinical evaluation, or autopsy data. The outcomes were evaluated for significance by calculating the rate ratio and 95% confidence interval. RESULTS: A total of 41 patients (22.7%) were diagnosed with venous thromboembolism, 29 (70.7%) with PE, 8 (19.5%) with PE and DVT, and 4 (9.8%) with DVT. Seven studies were considered nondiagnostic. Seventeen deaths occurred within 30 days of CTA/CTV, of which none was felt to be related to PE/DVT. Of the 140 studies read as negative or nondiagnostic, 4 were determined to have venous thromboembolism (3 PEs and 1 DVT) within 30 days of the initial study (NPV = 97.1%). If patients who received prophylactic anticoagulation or inferior vena cava interruption (n = 25) were excluded, NPV decreases to 96.5% CONCLUSION: A negative CTPA/CTV is reliable for the exclusion of significant venous thromboembolism in ICU patients.

Deep learning to convert unstructured CT pulmonary angiography reports into structured reports.

BACKGROUND: Structured reports have been shown to improve communication between radiologists and providers. However, some radiologists are concerned about resultant decreased workflow efficiency. We tested a machine learning-based algorithm designed to convert unstructured computed tomography pulmonary angiography (CTPA) reports into structured reports. METHODS: A self-supervised convolutional neural network-based algorithm was trained on a dataset of 475 manually structured CTPA reports. Labels for individual statements included "pulmonary arteries," "lungs and airways," "pleura," "mediastinum and lymph nodes," "cardiovascular," "soft tissues and bones," "upper abdomen," and "lines/tubes." The algorithm was applied to a test set of 400 unstructured CTPA reports, generating a predicted label for each statement, which was evaluated by two independent observers. Per-statement accuracy was calculated based on strict criteria (algorithm label counted as correct if the statement unequivocally contained content only related to that particular label) and a modified criteria, accounting for problematic statements, including typographical errors, statements that did not fit well into the classification scheme, statements containing content for multiple labels, etc. RESULTS: Of the 4,157 statements, 3,806 (91.6%) and 3,986 (95.9%) were correctly labeled by the algorithm using strict and modified criteria, respectively, while 274 (6.6%) were problematic for the manual observers to label, the majority of which (n = 173) were due to more than one section being included in one statement. CONCLUSION: This algorithm showed high accuracy in converting free-text findings into structured reports, which could improve communication between radiologists and clinicians without loss of productivity and provide more structured data for research/data mining applications.

Acute traumatic aortic injury: imaging evaluation and management.

Despite recent advances in prehospital care, multidetector computed tomographic (CT) technology, and rapid definitive therapy, trauma to the aorta continues to be a substantial source of morbidity and mortality in patients with blunt trauma. The imaging evaluation of acute aortic injuries has undergone radical change over the past decade, mostly due to the advent of multidetector CT. Regardless of recent technologic advances, imaging of the aorta in the trauma setting remains a multimodality imaging practice, and thus broad knowledge by the radiologist is essential. Likewise, the therapy for acute aortic injuries has changed substantially. Though open surgical repair continues to be the mainstay of therapy, percutaneous endovascular repair is becoming commonplace in many trauma centers. Here, the historical and current status of imaging and therapy of acute traumatic aortic injuries will be reviewed.

Pulmonary nodule volume: effects of reconstruction parameters on automated measurements--a phantom study.

PURPOSE: To prospectively evaluate in a phantom the effects of reconstruction kernel, field of view (FOV), and section thickness on automated measurements of pulmonary nodule volume. MATERIALS AND METHODS: Spherical and lobulated pulmonary nodules 3-15 mm in diameter were placed in a commercially available lung phantom and scanned by using a 16-section computed tomographic (CT) scanner. Nodule volume (V) was determined by using the diameters of 27 spherical nodules and the mass and density values of 29 lobulated nodules measured by using the formulas V = (4/3)pi r(3) (spherical nodules) and V = 1000 x (M/D) (lobulated nodules) as reference standards, where r is nodule radius; M, nodule mass; and D, wax density. Experiments were performed to evaluate seven reconstruction kernels and the independent effects of FOV and section thickness. Automated nodule volume measurements were performed by using computer-assisted volume measurement software. General linear regression models were used to examine the independent effects of each parameter, with percentage overestimation of volume as the dependent variable of interest. RESULTS: There was no substantial difference in the accuracy of volume estimations across the seven reconstruction kernels. The bone reconstruction kernel was deemed optimal on the basis of the results of a series of statistical analyses and other qualitative findings. Overall, volume accuracy was significantly associated (P < .0001) with larger reference standard-measured nodule diameter. There was substantial overestimation of the volumes of the 3-5-mm nodules measured by using the volume measurement software. Decreasing the FOV facilitated no significant improvement in the precision of lobulated nodule volume measurements. The accuracy of volume estimations--particularly those for small nodules--was significantly (P < .0001) affected by section thickness. CONCLUSION: Substantial, highly variable overestimation of volume occurs with decreasing nodule diameter. A section thickness that enables the acquisition of at least three measurements along the z-axis should be used to measure the volumes of larger pulmonary nodules.

Iso-osmolality versus low-osmolality iodinated contrast medium at intravenous contrast-enhanced CT: effect on kidney function.

PURPOSE: To determine the effects of iso-osmolality contrast medium compared with a low-osmolality agent on renal function (serum creatinine [SCr] and glomerular filtration rate [GFR]) in high-risk patients undergoing intravenous contrast material-enhanced CT. MATERIALS AND METHODS: This HIPAA-compliant study was IRB-approved; formal consent was obtained. One hundred seventeen patients (83 men, 34 women; mean age, 64.3 years; range, 18-86 years) with decreased renal function underwent contrast-enhanced CT with either iso-osmolality iodixanol (n = 61) or low-osmolality iopromide (n = 56). Outcome measures were of SCr increase or GFR decrease for 3 days after CT, a SCr increase (of >or=0.5 mg/dL [44.2 micromol/L, 25%] or >or=1.0 mg/dL [88.4 micromol/L, 50%]), a GFR reduction (of >or=5 mL/min), and patient outcome at 30- and 90-day follow-up. RESULTS: Iodixanol decreased SCr (mean +/- standard deviation) from 1.77 mg/dL +/- 0.24 (156.47 micromol/L +/- 21.22) at baseline to 1.65 mg/dL +/- 0.35 (145.86 micromol/L +/- 30.94, P = .046) at day 1, 1.73 mg/dL +/- 0.53 (152.93 micromol/L +/- 46.85, not significant) at day 2, and 1.73 mg/dL +/- 0.55 (152.93 micromol/L +/- 48.62, not significant) at day 3 (not significant). Iopromide increased SCr from 1.75 mg/dL +/- 0.32 (154.7 micromol/L +/- 28.29) at baseline to 1.8 mg/dL +/- 0.42 (159.12 micromol/L +/- 15.59) at day 1, 1.77 mg/dL +/- 0.49 (156.47 micromol/L +/- 43.32) at day 2, and 1.77 mg/dL +/- 0.62 (156.47 micromol/L +/- 54.81) at day 3 (not significant). Iodixanol increased and iopromide decreased GFR on all 3 days after CT (not significant). Fewer patients in the iodixanol group (8.5%) than in the iopromide group (27.8%) had SCr increase 0.5 mg/dL or higher (>or=25%, P = .012). Two patients in each group had SCr increase of 1.0 mg/dL or more (not significant). More patients in the iopromide group (42.3%) than in the iodoxanol group (24.1%) had a GFR reduction of 5 mL/min or higher (P = .0426). No patient had a contrast material-related adverse event at 30- or 90-day follow-up. CONCLUSION: Intravenous contrast material application in high-risk patients is unlikely to be associated with permanent adverse outcomes. SCr levels after contrast material administration are lower in iodixanol than iopromide groups.

Right heart: split-bolus injection of diluted contrast medium for visualization at coronary CT angiography.

PURPOSE: To retrospectively compare a split-bolus contrast medium injection protocol with a biphasic and a monophasic protocol in terms of visualization of the right and left heart, contrast medium-related streak artifacts, and level of attenuation in the cardiac chambers and coronary arteries at coronary computed tomographic (CT) angiography. MATERIALS AND METHODS: The human research committee approved this HIPAA-compliant study and waived informed consent. Seventy-five patients had undergone 64-section coronary CT angiography: 25 were injected by using a monophasic, contrast-medium-only protocol with a single-syringe injector; 25 were injected by using a biphasic protocol with a dual-syringe injector; and 25 were injected by using a split-bolus protocol with a dual-syringe injector and an initial bolus of contrast medium followed by 50 mL of a 70%:30% saline-to-contrast medium mixture and a 30-mL saline chaser. Two radiologists rated the visualization of right and left heart structures and the degree of streak artifacts. One observer performed attenuation measurements of the cardiac chambers and of the coronary arteries. Data were analyzed with one-way analysis of variance and Duncan post-hoc multiple comparison procedures. RESULTS: Data for 27 women and 48 men (mean age, 62 years) were included. Mean contrast medium attenuation in the right heart was significantly (P < .001) higher in the split-bolus group than in the biphasic injection group but was significantly (P < .001) lower than in the monophasic injection group. For the left heart and the coronary arteries, there were no significant differences among the three groups. Artifacts occurred less frequently (P < .001) in the biphasic and split-bolus groups than in the monophasic group. Visualization of right heart structures was rated significantly (P < .05) better in the split-bolus group than in the two other groups, while there was no difference for visualization of left heart structures. CONCLUSION: Split-bolus injection provides sufficient attenuation for visualization of the right heart, while streak artifacts from high-attenuation contrast material can generally be avoided and arterial attenuation is maintained.

Pulmonary nodules detected at cardiac CT: comparison of images in limited and full fields of view.

OBJECTIVE: The purpose of this study was to compare the frequency of detection of pulmonary nodules on cardiac CT scans acquired with a limited field of view with the frequency of detection at full field of view. CONCLUSION: Viewing of cardiac CT scans obtained only at a limited field of view can result in missing more than 67% of nodules larger than 1 cm and more than 80% of nodules smaller than 1 cm.

Acute traumatic thoracic aortic injuries: experience with 64-MDCT.

OBJECTIVE: At some institutions, catheter angiography is used for confirmation of aortic injuries and equivocal MDCT findings. Because of the speed and efficiency of 64-MDCT, we believe that diagnostic catheter angiography may be obsolete. The purpose of this study was to review our experience with 64-MDCT in the evaluation of acute traumatic aortic injury (ATAI). MATERIALS AND METHODS: The trauma registry at a level 1 trauma center was reviewed to find cases of ATAI occurring between March 1, 2005, and July 31, 2007. MDCT images were correlated with transcatheter angiograms when obtained. Surgical and clinical reports were reviewed to confirm abnormal and normal findings and the stability of the conditions of patients undergoing conservative treatment. RESULTS: After level 1 or level 2 trauma, 1,344 patients underwent contrast-enhanced 64-MDCT. Twenty-four patients (1.79%) were found to have 25 aortic injuries. All patients had direct MDCT signs of ATAI. Ten catheter angiograms were obtained after MDCT. The presence of direct signs was confirmed in three cases. In five cases, indirect signs were found to be normal findings. In two cases, the findings remained equivocal after MDCT and conventional angiography. Fourteen patients underwent surgical repair of the aorta, six underwent conservative management, and four patients died of other injuries. No patient with equivocal or indirect findings needed surgical repair. The sensitivity of 64-MDCT was 96.0%; specificity, 99.8%; positive predictive value, 92.3%; negative predictive value, 99.9%; and accuracy, 99.8%. CONCLUSION: Direct signs of ATAI on contrast-enhanced 64-MDCT scans do not have to be confirmed with catheter angiography. In our population, diagnostic transcatheter angiography was of limited value for clarifying equivocal or indirect MDCT findings.

Screening for lung cancer.

OBJECTIVE: The purpose of our review is to discuss the current state of lung cancer screening using CT in the context of defined criteria for effective screening. CONCLUSION: Although there are hopeful developments in lung cancer screening, a number of unresolved issues must be answered before adopting screening on a large scale. Currently no data exist to suggest that lung cancer screening with CT will result in a decrease in lung cancer mortality.

Is e-mail communication effective in changing ordering patterns in the emergency department? A case study of computed tomography for pulmonary embolus.

RATIONALE AND OBJECTIVES: We sought to evaluate the effectiveness of e-mail communication to reduce the utilization of computed tomography for pulmonary thromboembolism (PE) in young patients (aged 40 and under) in our institution. MATERIALS AND METHODS: An e-mail was sent to all of our institution's emergency department (ED) physicians in response to a series of negative PE studies in young females. The periods 90 days before and 90 days after were evaluated to assess the total number of PE studies performed in patients aged 40 and younger, the rate of positivity, and the utilization of D-dimer and ventilation/perfusion scans during each period. RESULTS: Over the 180-day period, a total of 65 PE studies were ordered in patients aged 40 and younger in the ED. Studies were positive for PE in 1 of 33 (3%) before the e-mail and 4 of 32 (12.5%) after (P = .343). There was no difference in the number of D-dimer studies ordered during each period for patients studied with computed tomography. Ventilation/perfusion scanning was not performed on any ED patients younger than 40 during the 180-day period. CONCLUSIONS: One-time e-mail communication was not effective in changing ED ordering habits of PE studies. Scant information exists in regard to effective clinician-to-clinician communication. Further evaluation for successful mechanisms to promote health practice reform and quality improvement is necessary.