Prevalence of pulmonary artery dilation in non-cystic fibrosis bronchiectasis: a computed tomography analysis from a cohort of the US Bronchiectasis and Nontuberculous Mycobacteria Research Registry.

Although pulmonary artery (PA) dilation is independently associated with significant morbidity and mortality in patients with pulmonary diseases irrespective of diagnosed pulmonary hypertension, its relationship with nontuberculous mycobacteria (NTM) is unknown. The Bronchiectasis and NTM Research Registry is a multicenter registry created to foster research in non-cystic fibrosis (CF) bronchiectasis and NTM lung disease. The majority of patients with non-CF bronchiectasis at Oregon Health & Science University have NTM infections. To determine the prevalence of PA dilation in these patients and its association with supplemental oxygen use, severity of bronchiectasis, tobacco use, and NTM in the sputum culture, we evaluated the chest computed tomography (CT) scans from 321 patients in a cross-sectional analysis. We measured the severity of bronchiectasis by applying modified Reiff criteria and measured the diameters of the PA and aorta (Ao), with PA dilation defined as a PA:Ao ratio >0.9. In our cohort, the mean age was 67.3 years and 83.2% were female. The mean modified Reiff score was 7.1, indicating moderate disease severity. Forty-two patients (13.1%) were found to have PA dilation. PA dilation was positively associated with the use of supplemental oxygen (P<0.001), but there was no association between PA dilation and NTM infection.

Prevalence of pulmonary artery dilation in non-cystic fibrosis bronchiectasis: A CT analysis from a cohort of the US Bronchiectasis and Nontuberculous Mycobacteria Research Registry.

Although pulmonary artery (PA) dilation is independently associated with significant morbidity and mortality in patients with pulmonary diseases irrespective of diagnosed pulmonary hypertension, its relationship to nontuberculous mycobacteria (NTM) is unknown. To determine the prevalence of PA dilation in patients with NTM-predominant non-CF bronchiectasis, we evaluated the chest computed tomography (CT) scans from 321 patient in the United States based Bronchiectasis and NTM Research Registry. The majority of our cohort had NTM infection. We measured the severity of bronchiectasis using modified Reiff criteria and measured the diameters of the PA and aorta (Ao), with PA dilation defined as a PA:Ao ratio > 0.9. Forty-two patients (13%) were found to have PA dilation. PA dilation was positively associated with the use of supplemental oxygen (p < 0.001), but there was no association between PA dilation and NTM infection.

ICU imaging.

Chest radiography serves a crucial role in imaging of the critically ill. Its uses include diagnosis and monitoring of commonly encountered pulmonary parenchymal and pleural space abnormalities. It is also important in evaluating monitoring and support devices and associated complications. CT, another useful imaging modality in select patients, can better characterize pulmonary parenchymal and pleural space disease.

Differentiating diaphragmatic paralysis and eventration.

RATIONALE AND OBJECTIVES: Although elevation of the diaphragm can be appreciated on conventional PA and lateral chest radiography, the modality is commonly viewed as inadequate to differentiate diaphragmatic paralysis from eventration. Our objective was to qualitatively and quantitatively measure the utility of chest radiography in determining the presence or absence of diaphragmatic paralysis in patients with an elevated diaphragm. MATERIALS AND METHODS: A retrospective analysis of chest radiographs in 32 patients, whom underwent fluoroscopic sniff test for elevated diaphragm, was performed. Diaphragm function was graded by a senior radiology resident, as either "paralyzed" or "non-paralyzed," based on appearance/shape of elevated hemidiaphragm on PA and lateral radiograph. The diaphragm position and shape for all patients were determined using measurements relating to skeletal structures and radius of curvature, respectively. These results were correlated with the results of the fluoroscopic sniff tests. RESULTS: Of 32 patients with elevated diaphragm on chest radiograph, 17 had diaphragmatic paralysis confirmed with fluoroscopic sniff test. Our results indicate that the radius of curvature or shape of the diaphragm on lateral chest radiograph is the most important factor for detection of the presence or absence of diaphragmatic paralysis. HH/APD > 0.28 suggests against paralysis. CONCLUSION: Conventional chest radiography appears to be a useful modality for assessment of the functional status of an elevated diaphragm. Based on our results, evaluation of the shape of an elevated diaphragm may preclude the need for fluoroscopic sniff test to determine diaphragmatic paralysis.

High resolution radiographic and fine immunologic definition of TB disease progression in the rhesus macaque.

Mycobacterium tuberculosis infection in non-human primates parallels human tuberculosis, and provides a valuable vaccine evaluation model. However, this model is limited by the availability of real-time, non-invasive information regarding disease progression. Consequently, we have combined computed tomography scanning with enumeration of antigen-specific T cell responses. Four rhesus monkeys were infected with M. tuberculosis strain H37Rv (1000 cfu) in the right lower lobe via a bronchoscope. All uniformly developed progressive tuberculosis, and required euthanasia at 12 weeks. Computed tomography scanning provided detailed real-time imaging of disease progression. At necropsy, computed tomography and pathohistologic findings were tightly correlated, and characteristic of human disease. Immunologic monitoring demonstrated progressive evolution of high frequency M. tuberculosis-specific CD4(+) and CD8(+) T cell responses. Peripheral blood effector cell frequencies were similar to those observed in tissues. In summary, computed tomography scanning in conjunction with immunologic monitoring provides a non-invasive, accurate, and rapid assessment of tuberculosis in the non-human primate.

Intensive care unit imaging.

Chest radiography serves a crucial role in imaging of the critically ill. It is essential in ensuring the proper positioning of support and monitoring equipment, and in evaluating for potential complications of this equipment. The radiograph is useful in diagnosing and evaluating the progression of atelectasis, aspiration, pulmonary edema, pneumonia, and pleural fluid collections. Computed tomography can be useful when the clinical and radiologic presentations are discrepant, the patient is not responding to therapy, or in further defining the pattern and distribution of a radiographic abnormality.

The impact of anatomic tumor location on inter-fraction tumor motion during lung stereotactic body radiation therapy (SBRT).

PURPOSE: Narrow PTV margins and steep dose gradients underscore the importance of evaluating breathing-associated tumor motion for lung SBRT. The specific aim of this study was to determine the impact of anatomic tumor location on inter-fraction tumor motion. METHODS AND MATERIALS: Forty-one patients underwent standard free-breathing 4DCT simulation and daily image-guidance 4DCTs during lung SBRT. Absolute tumor motion amplitude in the mediolateral (ML), anterior-posterior (AP), and superior-inferior (SI) directions was analyzed from 159 total 4DCT scans (simulation and daily pre-treatment). RESULTS: Overall, the inter-fraction tumor motion amplitude in the ML, AP, and SI directions was small (mean ≤2.5 mm). Similarly, while both upper lobe (UL) and lower lobe (LL) tumors exhibited limited inter-fraction motion in both the ML and AP directions (mean ≤2.2 mm), tumors in the LL had increased inter-fraction motion in the SI direction compared to UL tumors (mean 4.3±4.0 mm vs. 1.7±1.7 mm, p=0.008). Moreover, 28.6% (n=4) of LL tumors exhibited mean inter-fraction motion along the SI direction >5 mm (all of which resided in the supra-diaphragmatic basal segments of the LL). CONCLUSIONS: Mean inter-fraction tumor motion amplitude along the SI direction exceeded our PTV margins (an isotropic 5 mm expansion of the ITV) in 28.6% of LL tumors (all of which resided in the basal segments). These results suggest that typical ITV-to-PTV margins may be insufficient for a subset of LL lesions and that increased PTV margins, daily breathing motion re-assessment and/or adaptive re-planning may benefit patients with supra-diaphragmatic tumors in the LL.

Management of life-threatening pulmonary leukostasis with single agent imatinib mesylate during CML myeloid blast crisis.

Pulmonary leukostasis is a rare but serious and often fatal complication of chronic myeloid leukemia (CML) in blast crisis and acute myeloid leukemia. Treatment options are limited for these patients. Imatinib mesylate (STI-571, Gleevec, Novartis) is a potent and selective inhibitor of the BCR-abl tyrosine kinase, the molecular abnormality that causes CML. The case of a 74-year-old man with a history of CML who presented in myeloid blast crisis with pulmonary leukostasis characterized by increasing dyspnea, hypoxemia, fever, and impending respiratory failure is reported. The patient was treated with single agent imatinib mesylate (IM) with rapid decrease in his white blood cell count (WBC) and marked improvement in his respiratory status. No electrolyte abnormalities consistent with tumor lysis syndrome were observed. IM may be an effective single agent therapy for pulmonary leukostasis in patients with CML blast crisis who are at the risk for tumor lysis.

Small pulmonary nodules on CT accompanying surgically resectable lung cancer: likelihood of malignancy.

SUMMARY: The aim of this study was to determine the likelihood of malignancy in small nodules in the nonprimary lobe in patients with resectable bronchogenic carcinoma. In 141 patients who underwent curative resection of bronchogenic carcinoma and had adequate follow-up CT examinations, the presence of small nodules in the nonprimary lobe preoperatively and change of preexisting nodules, if any, was assessed. The criteria used to determine benignity of a nodule was stability or decrease in size for 24 months on CT. Histopathology of the nodules was reviewed for an additional 10 patients who underwent surgical biopsy for an accompanying nodule before curative surgery. Sixty-two (44%) of 141 patients had a total of 138 small (< or = 10 mm) nodules in the nonprimary lobes (< 5 mm in 113, 5-10 mm in 25). Of these 138 nodules, 132 were benign with only six nodules malignant (with histopathologic confirmation for the enlarging nodules). The 132 benign nodules showed no change (n = 120), decrease in size (n = 11), or increase in size (n = 1) on follow-up studies, with the single enlarging nodule proved benign on biopsy. In 10 patients who had a preoperative biopsy of a single preexisting nodule in the nonprimary lobe (< 5 mm = 1; 5-10 mm = 5; > 10 mm = 4) two proved to be malignant (both > 10 mm) and eight were benign. Most small (< 10 mm) nodules associated with resectable bronchogenic carcinoma are benign, consistent with published results of other studies. However, a small number of nodules are malignant and CT does not reliably distinguish between benign and malignant nodules.

Blunt nonaortic chest trauma: radiographic and CT findings.

Following initial clinical evaluation and stabilization of a patient who has sustained blunt chest trauma, imaging has an important role in the evaluation of thoracic injuries. The initial study is the chest radiograph. However, chest CT is being used with increased frequency in the evaluation of blunt chest trauma. Although CT is used primarily to assess for traumatic aortic injuries, it is also useful in the evaluation of pulmonary and bronchial, airway, skeletal and diaphragmatic injury. The aim of this article is to review the characteristic imaging findings of pulmonary and bronchial, esophageal, thoracic, skeletal and diaphragmatic injuries.

Direct findings of aortic injury on contrast-enhanced CT in surgically proven traumatic aortic injury: a multi-centre review.

OBJECTIVE: To review the contrast-enhanced CT findings in surgically proven traumatic aortic injury (TAI). MATERIALS AND METHODS: We searched the trauma registries of three academic medical centres from 1994 to 2000 and found 34 patients with surgically proven TAI that received pre-operative contrast-enhanced chest CT. Two chest radiologists recorded by consensus the size and location of direct (pseudoaneurysm, intimal flap) and indirect (mediastinal haematoma) findings of TAI. The imaging findings were correlated with surgical reports. RESULTS: Direct findings of aortic injury (pseudoaneurysm or intimal flap) were seen on contrast enhanced CT in all patients and confirmed at surgery. Specifically, a pseudoaneurysm was seen in 33 (97%), presenting either as a focal bulge in 22 (65%) or as more diffuse aneurysmal enlargement in 11 (32%). An intimal flap was identified in 31 cases (91%). A periaortic haematoma was seen in 31 cases (91%). In the three patients without periaortic haematoma, the only indications of aortic injury were a focal pseudoaneurysm in two (6%) and an intimal flap in one (3%). CONCLUSION: In this series of surgically proven TAI, direct findings of aortic injury were seen in all cases. Aortic tear occurred without mediastinal haematoma in 9% (3/34) of patients.

Viral pneumonias in adults: radiologic and pathologic findings.

Numerous viruses, including influenza virus, measles virus, Hantavirus, adenovirus, herpesviruses, varicella-zoster virus, cytomegalovirus, and Epstein-Barr virus, can cause lower respiratory tract infection in adults. Viral pneumonia in adults can be classified into two clinical groups: so-called atypical pneumonia in otherwise healthy hosts and viral pneumonia in immunocompromised hosts. Influenza virus types A and B cause most cases of viral pneumonia in immunocompetent adults. Immunocompromised hosts are susceptible to pneumonias caused by cytomegalovirus, herpesviruses, measles virus, and adenovirus. The radiographic findings, which consist mainly of patchy or diffuse ground-glass opacity with or without consolidation and reticular areas of increased opacity, are variable and overlapping. Computed tomographic findings, which are also overlapping, consist of poorly defined centrilobular nodules, ground-glass attenuation with a lobular distribution, segmental consolidation, or diffuse ground-glass attenuation with thickened interlobular septa. The radiologic findings reflect the variable extents of the histopathologic features: diffuse alveolar damage (intraalveolar edema, fibrin, and variable cellular infiltrates with a hyaline membrane), intraalveolar hemorrhage, and interstitial (intrapulmonary or airway) inflammatory cell infiltration. Clinical information such as patient age, immune status, community outbreaks, symptom onset and duration, and presence of a rash remain important aids in diagnosis of viral causes.