H P McAdams

Lentil aspiration pneumonia: radiographic and CT findings.

Aspiration of leguminous vegetables can cause a granulomatous pneumonitis know as lentil aspiration pneumonia that manifest on radiologic studies with small, poorly defined nodular opacities. We report two cases of lentil aspiration pneumonia that manifested with nodules up to 1.0 cm in diameter on radiographs and CT, simulating metastases.

Hyperpolarized Gas MR Imaging: Technique and Applications

Functional imaging offers information more sensitive to changes in lung structure and function. Hyperpolarized helium ((3)He) and xenon ((129)Xe) MR imaging of the lungs provides sensitive contrast mechanisms to probe changes in pulmonary ventilation, microstructure, and gas exchange. Gas imaging has shifted to the use of (129)Xe. Xenon is well-tolerated. (129)Xe is soluble in pulmonary tissue, which allows exploring specific lung function characteristics involved in gas exchange and alveolar oxygenation. Hyperpolarized gases and (129)Xe in particular stand to be an excellent probe of pulmonary structure and function, and provide sensitive and noninvasive biomarkers for pulmonary diseases.

Thoracic imaging features of patients with antiphospholipid antibodies.

PURPOSE Our aim was to determine the thoracic manifestations of patients with antiphospholipid antibodies (APAs). METHOD We performed a retrospective review of the clinical records and thoracic imaging studies of 88 patients (63 women, 25 men; mean age 47 years) with APAs to determine the spectrum of thoracic disease. RESULTS Nine patients (10%) had thoracic abnormalities, including eight with pulmonary embolism (PE) and one with aortic thrombus. One patient with PE had subclavian vein thrombosis. Coexistent thromboses included deep venous thrombosis of the leg in six patients. CONCLUSION PE was the most common thoracic abnormality in our patients. The presence of these antibodies should be suspected in patients with PE of otherwise unexplained etiology.

Abnormalities in hyperpolarized 129Xe magnetic resonance imaging and spectroscopy in two patients with pulmonary vascular disease

The diagnosis of pulmonary vascular disease (PVD) is usually based on hemodynamic and/or clinical criteria. Noninvasive imaging of the heart and proximal vasculature can also provide useful information. An alternate approach to such criteria in the diagnosis of PVD is to image the vascular abnormalities in the lungs themselves. Hyperpolarized (HP) 129Xe magnetic resonance imaging (MRI) is a novel technique for assessing abnormalities in ventilation and gas exchange in the lungs. We applied this technique to two patients for whom there was clinical suspicion of PVD. Two patients who had significant hypoxemia and dyspnea with no significant abnormalities on computed tomography imaging or ventilation-perfusion scan and only mild or borderline pulmonary arterial hypertension at catheterization were evaluated. They underwent HP 129Xe imaging and subsequently had tissue diagnosis obtained from lung pathology. In both patients, HP 129Xe imaging demonstrated normal ventilation but markedly decreased gas transfer to red blood cells with focal defects on imaging, a pattern distinct from those previously described for idiopathic pulmonary fibrosis or obstructive lung disease. Pathology on both patients later demonstrated severe PVD. These findings suggest that HP 129Xe MRI may be useful in the diagnosis of PVD and monitoring response to therapy. Further studies are required to determine its sensitivity and specificity in these settings.

Novel Magnetic Resonance Imaging for Assessment of Bronchial Stenosis in Lung Transplant Recipients

Bronchial stenosis in lung transplant recipients is a common disorder that adversely affects clinical outcomes. It is evaluated by spirometry, CT scanning, and bronchoscopy with significant limitations. We hypothesize that MRI using both ultrashort echo time (UTE) scans and hyperpolarized (HP) 129Xe gas can offer structural and functional assessment of bronchial stenosis seen after lung transplantation. Six patients with lung transplantation–related bronchial stenosis underwent HP 129Xe MRI and UTE MRI in the same session. Three patients subsequently underwent airway stent placement and had repeated MRI at 4‐week follow‐up. HP 129Xe MRI depicted decreased ventilation distal to the stenotic airway. After airway stent placement, MRI showed that low‐ventilation regions had decreased (35% vs. 27.6%, p = 0.006) and normal‐ventilation regions had increased (17.9% vs. 27.6%, p = 0.04) in the stented lung. Improved gas transfer was also seen on 129Xe MRI. There was a good correlation between UTE MRI and independent bronchoscopic airway diameter assessment (Pearson correlation coefficient = 0.92). This pilot study shows that UTE and HP 129Xe MRI are feasible in patients with bronchial stenosis related to lung transplantation and may provide structural and functional airway assessment to guide treatment. These conclusions need to be confirmed with larger studies.

Hyperpolarized Gas MRI: Technique and Applications

Functional imaging offers information more sensitive to changes in lung structure and function. Hyperpolarized helium ((3)He) and xenon ((129)Xe) MR imaging of the lungs provides sensitive contrast mechanisms to probe changes in pulmonary ventilation, microstructure, and gas exchange. Gas imaging has shifted to the use of (129)Xe. Xenon is well-tolerated. (129)Xe is soluble in pulmonary tissue, which allows exploring specific lung function characteristics involved in gas exchange and alveolar oxygenation. Hyperpolarized gases and (129)Xe in particular stand to be an excellent probe of pulmonary structure and function, and provide sensitive and noninvasive biomarkers for pulmonary diseases.

Hyperpolarized Gas MR Imaging

Functional imaging offers information more sensitive to changes in lung structure and function. Hyperpolarized helium ((3)He) and xenon ((129)Xe) MR imaging of the lungs provides sensitive contrast mechanisms to probe changes in pulmonary ventilation, microstructure, and gas exchange. Gas imaging has shifted to the use of (129)Xe. Xenon is well-tolerated. (129)Xe is soluble in pulmonary tissue, which allows exploring specific lung function characteristics involved in gas exchange and alveolar oxygenation. Hyperpolarized gases and (129)Xe in particular stand to be an excellent probe of pulmonary structure and function, and provide sensitive and noninvasive biomarkers for pulmonary diseases.