Kirk G. Jordan

Distinguishing Hantavirus pulmonary syndrome from acute respiratory distress syndrome by chest radiography : Are there different radiographic manifestations of increased alveolar permeability ?

Hantavirus infection may cause diffuse air space disease, termed hanta-virus pulmonary syndrome (HPS). The authors sought to determine if chest radiographs could differentiate HPS from typical acute respiratory distress syndrome (ARDS). The authors identified patients with either HPS (n = 11) or acute ARDS (n = 32) and selected the earliest chest radiograph showing diffuse airspace disease, and a chest radiograph taken 24 to 48 hours previously. Thoracic and general radiologists first viewed the chest radiograph showing diffuse air space disease, and ranked the likelihood that each case represented HPS versus ARDS. Afterward, readers viewed earlier chest radiographs and rescored each case. Receiver operating characteristic (ROC) curves from both scoring sessions were generated. The mean areas under the ROC curves for the entire group was 0.83 ± 0.12 initially, and improved to 0.87 ± 0.09 (p < 0.05) after viewing prior chest radiographs. Receiver operating characteristic curves of thoracic radiologists described greater areas than those of general radiologists both before and after viewing prior chest radiographs; 0.95 ± 0.01 versus 0.78 ± 0.08 (p < 0.05) and 96 ± 0.02 versus 0.80 ± 0.05 (p < 0.05). The mean sensitivity and specificity of chest radiograph interpretation for HPS was 86 ± 13% and 74 ± 11%, respectively. Chest radiographs can differentiate HPS from ARDS. Accuracy is improved by the use of serial radiographs and more highly trained readers. The chest radiograph findings may represent differences in the extent of alveolar epithelial damage seen in HPS and ARDS.

Quantification of Regional Interstitial Lung Disease from CT-derived Fractional Tissue Volume: A Lung Tissue Research Consortium Study

RATIONALE AND OBJECTIVES Evaluation of chest computed tomography (CT) is usually qualitative or semiquantitative, resulting in subjective descriptions often by different observers over time and imprecise determinations of disease severity within distorted lobes. There is a need for standardized imaging biomarkers to quantify regional disease, maximize diagnostic yield, and facilitate multicenter comparisons. We applied lobe-based voxelwise image analysis to derive regional air (Vair) and tissue (Vtissue) volumes and fractional tissue volume (FTV = tissue/[tissue+air] volume) as internally standardized parameter for assessing interstitial lung disease (ILD). MATERIALS AND METHODS High-resolution CT was obtained at supine and prone end-inspiration and supine end-expiration in 29 patients with ILD and 20 normal subjects. Lobar Vair, Vtissue, and FTV were expressed along standard coordinate axes. RESULTS In normal subjects from end-inspiration to end-expiration, total Vair declined ~43%, FTV increased ~80%, but Vtissue remained unchanged. With increasing ILD, Vair declined and Vtissue rose in all lobes; FTV increased with a peripheral-to-central progression inversely correlated to spirometry and lung diffusing capacity (r(2) = 0.57-0.75, prone end-inspiration). Inter- and intralobar coefficients of variation of FTV increased 84-148% in mild-to-moderate ILD, indicating greater spatial heterogeneity, then normalized in severe ILD. Analysis of discontinuous images incurs <3% error compared to consecutive images. CONCLUSIONS These regional attenuation-based biomarkers could quantify heterogeneous parenchymal disease in distorted lobes, detect mild ILD involvement in all lobes and describe the pattern of disease progression. The next step would be to study a larger series, examine reproducibility and follow longitudinal changes in correlation with clinical and functional indices.

Etiology of the Widened Mediastinum: Blunt Thoracic Trauma

Most centers continue to use conventional chest radiography as the principal screening modality for the detection of mediastinal hemorrhage and potential injury to the aorta or great vessels after blunt decelerating trauma. Of the many radiographic signs proposed to suggest potential injury, the mos

Simultaneous diagnosis of acute cholecystitis, intestinal malrotation, and duodenal diverticulum by cholescintigraphy

A 68-year-old man presented with intermittent episodes of epigastric and right upper quadrant pain and an elevated white blood cell count, 3 months after a hemicolectomy for adenocarcinoma of the transverse colon. Hepatobiliary scintigraphy demonstrated nonvisualization of the gallbladder consistent with acute cholecystitis. In addition, activity within the proximal small bowel revealed malrotation. Delayed imaging also demonstrated a focal area of activity representing a large duodenal diverticulum. Subsequent barium small bowel series and laparotomy with cholecystectomy confirmed all three findings initially noted by scintigraphy

Pulmonary vasculitis: Diagnosis and endovascular therapy

Pulmonary vasculitides are caused by a heterogeneous group of diseases with different clinical features and etiologies. Radiologic manifestations depend on the predominant type of vessel involved, which are grouped into large, medium, or small-sized vessels. Diagnosing pulmonary vasculitides is a challenging task, and radiologists play an important role in their management by providing supportive evidence for diagnosis and opportunities for minimally invasive therapy. This paper aims to present a practical approach for understanding the vasculitides that can affect the pulmonary vessels and lungs. We will describe and illustrate the main radiologic findings, discussing opportunities for minimally invasive treatment.

Cross-sectional imaging of sinus of Valsalva aneurysms: Lessons learned

Sinus of Valsalva aneurysm, dilatation of one or more of the aortic sinuses, is a rare but important aortic root defect, which can be a cause of some serious cardiac sequels. The purpose of this article is to review the etiopathogenesis, relevant anatomy, clinical manifestations, potential complications, multimodality imaging features, and management of this rare but important entity of sinus of Valsalva.

Retrocardiac mass presenting with hematemesis

Two patients presented to the emergency room with multiple episodes of hematemesis. Chest radiographs on each patient demonstrated a retrocardiac mass. Computed tomography revealed these masses to be vascular and consistent with paraesophageal varices. Portal-systemic collaterals can be seen with various imaging modalities; in patients with portal hypertension, these varices may present as a common cause of an upper gastrointestinal bleed and hematemesis.