Causative factors, imaging findings, and CT course of round atelectasis.

OBJECTIVE: To assess causative factors, associated imaging findings, and CT course of round atelectasis (RA). MATERIALS AND METHODS: We retrospectively reviewed CT reports for "round" or "rounded atelectasis" over a 5-year time frame. Patients with at least 2 CT scans a minimum of 6 months apart were included. Electronic medical records and clinical and imaging follow-up was reviewed for all cases. RESULTS: Study population included 50 individuals with mean age of 63 years, and 59 unique instances of RA. The most commonly associated etiologies were hepatic hydrothorax (26%, n = 13) and asbestos exposure (26%), followed by post-infectious pleural inflammation (22%), congestive heart failure (12%), and end stage renal disease (8%). RA was found in the right lower lobe in over half of cases (n = 30). Association with one or more pleural abnormality was identified in all cases, including thickening (88%), fluid (60%), or calcification (40%). Nearly one third (n = 19) demonstrated intra-lesional calcification. In those who underwent PET/CT (20%), lesions demonstrated an average SUV of 2.2 (range 0-7.8). CT course over mean follow up of 32 months (range 6-126 months), demonstrated RA to remain stable (n = 26) or decrease (n = 26) in size in the majority (88%) of cases. CONCLUSION: Round atelectasis may arise from diverse etiologies beyond asbestos, and will most often decrease or remain stable in size over serial exams. Accurate identification may obviate the need for added diagnostic interventions.

Estimation of cardiovascular risk on routine chest CT: Ordinal coronary artery calcium scoring as an accurate predictor of Agatston score ranges.

BACKGROUND: Coronary artery calcium (CAC) is often identified on routine chest computed tomography (CT). The purpose of our study was to evaluate whether ordinal scoring of CAC on non-gated, routine chest CT is an accurate predictor of Agatston score ranges in a community-based population, and in particular to determine the accuracy of an ordinal score of zero on routine chest CT. METHODS: Two thoracic radiologists reviewed consecutive same-day ECG-gated and routine non-gated chest CT scans of 222 individuals. CAC was quantified using the Agatston scoring on the ECG-gated scans, and using an ordinal method on routine scans, with a score from 0 to 12. The pattern and distribution of CAC was assessed. The correlation between routine exam ordinal scores and Agatston scores in ECG-gated exams, as well as the accuracy of assigning a zero calcium score on routine chest CT was determined. RESULTS: CAC was most prevalent in the left anterior descending coronary artery in both single and multi-vessel coronary artery disease. There was a strong correlation between the non-gated ordinal and ECG-gated Agatston scores (r = 0.811, p < 0.01). Excellent inter-reader agreement (k = 0.95) was shown for the presence (total ordinal score ≥1) or absence (total ordinal score = 0) of CAC on routine chest CT. The negative predictive value for a total ordinal score of zero on routine CT was 91.6% (95% CI, 85.1-95.9). Total ordinal scores of 0, 1-3, 4-5, and ≥6 corresponded to average Agatston scores of 0.52 (0.3-0.8), 98.7 (78.2-117.1), 350.6 (264.9-436.3) and 1925.4 (1526.9-2323.9). CONCLUSION: Visual assessment of CAC on non-gated routine chest CT accurately predicts Agatston score ranges, including the zero score, in ECG-gated CT. Inclusion of this information in radiology reports may be useful to convey important information on cardiovascular risk, particularly premature atherosclerosis in younger patients.

Idiopathic interstitial pneumonias: a radiology-pathology correlation based on the revised 2013 American Thoracic Society-European Respiratory Society classification system.

The idiopathic interstitial pneumonias (IIPs) are a group of diffuse lung diseases that share many similar radiologic and pathologic features. According to the revised 2013 American Thoracic Society-European Respiratory Society classification system, these entities are now divided into major IIPs (idiopathic pulmonary fibrosis, idiopathic nonspecific interstitial pneumonia, respiratory bronchiolitis-associated interstitial lung disease, desquamative interstitial pneumonia, cryptogenic organizing pneumonia, and acute interstitial pneumonia), rare IIPs (idiopathic lymphoid interstitial pneumonia, idiopathic pleuroparenchymal fibroelastosis), and unclassifiable idiopathic interstitial pneumonias. Some of the encountered radiologic and histologic patterns can also be seen in the setting of other disorders, which makes them a diagnostic challenge. As such, the accurate classification of IIPs remains complex and is best approached through a collaboration among clinicians, radiologists, and pathologists, as the treatment and prognosis of these conditions vary greatly.

Plasma level of interferon γ induced protein 10 is a marker of sarcoidosis disease activity.

RATIONALE: Sarcoidosis is an idiopathic granulomatous disorder with heterogeneous clinical manifestations and variable prognosis. Monitoring disease activity is important to identify patients requiring treatment. Several cytokines have previously been shown to be elevated in the serum of patients with sarcoidosis and may be useful biomarkers of disease activity. OBJECTIVES: To identify novel biomarkers of sarcoidosis disease activity. To identify the relationship between plasma cytokines, disease severity and prognosis. METHODS: The study was approved by the institutional review board. Plasma concentration of 19 cytokines was measured in 112 subjects with chronic sarcoidosis and 52 matched controls, using the bead-based Milliplex xMAP multiplex technology. Plasma levels of individual cytokines were compared between the two groups, and between the groups with clinically active vs. inactive disease. Sensitivity, specificity and receiver operating characteristics curves were used to evaluate biomarker performance. Linear regression analyses were performed to identify associations between cytokine levels, pulmonary function tests and changes in pulmonary function. MEASUREMENTS AND MAIN RESULTS: Subjects with sarcoidosis had higher plasma levels of interferon gamma induced protein 10 (IP-10) and tumor necrosis factor α (TNFα). IP-10 had the highest sensitivity and specificity in identifying active disease. Higher levels of IP-10 and TNFα were associated with greater disease severity and better prognosis. CONCLUSIONS: IP-10 is a potentially useful biomarker of sarcoidosis and its severity.

Prospective validation of computed tomographic screening of the thoracolumbar spine in trauma.

OBJECTIVE: Concern for thoracolumbar spine (TLS) injuries after major trauma mandates immobilization pending radiographic evaluation. Current protocols use standard posteroanterior and lateral radiographs of the thoracolumbar spine (XR/TLS), but many patients also undergo abdominal or thoracic computed tomographic (CT) scanning. We sought to evaluate whether helical truncal CT scanning performed to evaluate visceral trauma images the spine as well as dedicated XR/TLS. METHODS: We prospectively studied 222 consecutive patients sustaining high-risk trauma requiring TLS screening because of clinical findings or altered mentation. The chest, abdomen, and pelvis were imaged with one intravenous contrast infusion. All patients had CT scan of the chest, abdomen, and pelvis (CT/CAP) and XR/TLS. Initial radiologic diagnoses were compared with the discharge diagnosis of acute fractures confirmed by thin-cut CT scan and/or clinical examination of the patient when alert. RESULTS: Of 222 patients studied, 215 were fully evaluated. Thirty-six (17%) had acute TLS fractures. The accuracy of CT/CAP for TLS fractures was 99% (95% confidence interval [CI], 96-100%). The accuracy of XR/TLS was 87% (95% CI, 82-92%). Sensitivity, specificity, and positive and negative predictive values were better for CT/CAP than for XR/TLS. CT/CAP found acute fractures XR/TLS missed, and correctly classified old fractures XR/TLS read as "possibly" acute. The total XR/TLS misclassification rate was 12.6% (95% CI, 8.4-19%); for CT/CAP it was 1.4% (95% CI, 0.3-3.3%). No fractures were missed by CT/CAP. No unstable fracture was missed by either technique. CONCLUSION: CT/CAP diagnoses TLS fractures more accurately than XR/TLS. Neither misses unstable fractures, but CT scanning finds small fractures that benefit by treatment and identifies chronic disease better. CT screening is far faster and shortens time to removal of spine precautions. CT scan-based diagnosis does not result in greater radiation exposure and improves resource use. Screening the TLS on truncal helical CT scanning performed for the evaluation of visceral injuries is more accurate than TLS imaging by standard radiography. CT/CAP should replace plain radiographs in high-risk trauma patients who require screening.

Massive pulmonary embolism: a comparison of radiological and clinical characteristics and outcomes.

STUDY OBJECTIVES: To describe the clinical features of radiographically massive pulmonary embolism (MPE). DESIGN: Retrospective analysis. SETTING: A 1,368-bed teaching hospital. PATIENTS OR PARTICIPANTS: Patients with pulmonary embolism between June 1997 and December 1999. INTERVENTIONS: Radiographic reports of patients with a radiographic diagnosis of pulmonary embolism were reviewed to determine whether MPE (>50% vascular occlusion) was present. For patients with MPE, vital signs, respiratory and cardiac symptoms, medical history, arterial blood gases, electrocardiographic (ECG) and echocardiographic results, treatment, and hospital mortality were recorded. MEASUREMENTS AND RESULTS: Fifty-four patients with MPE were identified. Patient age range was 28-91 years (mean 71 years). Symptoms were: dyspnea in 38 (70%), chest pain in 21 (38%), syncope in 12 (22%), palpitations in 6 (11%), systolic blood pressure <90 mmHg in 12 (22%), tachycardia (>120 beats/min) in 15 (28%) and tachypnea (respiratory rate >30) in 15 (28%). Pa O(2) (arterial partial pressure of oxygen) was less than 60 mmHg in 28 (71%) and the alveolar-arterial oxygen gradient was always greater than 20. ECG had an S1Q3T3 pattern in 6 (12%). Echocardiography revealed right ventricular dilatation in 12/31 (38%). Forty-nine patients received anticoagulation treatment, 4 (7%) received thrombolytic therapy with anticoagulation, 5 had inferior vena cava filters (IVC) alone, 6 received IVC filters with anticoagulation, and 2 received thrombolytic therapy, anticoagulation, and IVC filters. Eighteen (33%) patients were treated in the intensive care unit, 3 (5.5%) with mechanical ventilation. Fifty (93%) patients were eventually discharged and 4 (7%) died. Two of the deaths were not attributable to MPE. CONCLUSIONS: Patients with MPE usually present with dyspnea and hypoxemia, and most survive without thrombolytic therapy.