Lung imaging patterns in connective tissue disease-associated interstitial lung disease impact prognosis and immunosuppression response.

OBJECTIVES: Interstitial lung disease (ILD) in connective tissue diseases (CTD) have highly variable morphology. We aimed to identify imaging features and their impact on ILD progression, mortality and immunosuppression response. METHODS: Patients with CTD-ILD had high-resolution chest computed tomography (HRCT) reviewed by expert radiologists blinded to clinical data for overall imaging pattern (usual interstitial pneumonia [UIP]; non-specific interstitial pneumonia [NSIP]; organizing pneumonia [OP]; fibrotic hypersensitivity pneumonitis [fHP]; and other). Transplant-free survival and change in percent-predicted forced vital capacity (FVC) were compared using Cox and linear mixed effects models adjusted for age, sex, smoking, and baseline FVC. FVC decline after immunosuppression was compared with pre-treatment. RESULTS: Of 645 CTD-ILD patients, the frequent CTDs were systemic sclerosis (n = 215), rheumatoid arthritis (n = 127), and inflammatory myopathies (n = 100). NSIP was the most common pattern (54%), followed by UIP (20%), fHP (9%), and OP (5%). Compared with UIP, FVC decline was slower for NSIP (1.1%/year, 95%CI 0.2, 1.9) and OP (3.5%/year, 95%CI 2.0, 4.9), and mortality was lower for NSIP (HR 0.65, 95%CI 0.45, 0.93) and OP (HR 0.18, 95%CI 0.05, 0.57), but higher in fHP (HR 1.58, 95%CI 1.01, 2.40). The extent of fibrosis also predicted FVC decline and mortality. After immunosuppression, FVC decline was slower compared with pre-treatment in NSIP (by 2.1%/year, 95%CI 1.4, 2.8), with no change for UIP or fHP. CONCLUSION: Multiple radiologic patterns are possible in CTD-ILD, including a fHP pattern. NSIP and OP were associated with better outcomes and response to immunosuppression, while fHP had worse survival compared with UIP.

Canadian Association of Radiologists Thoracic Imaging Referral Guideline.

The Canadian Association of Radiologists (CAR) Thoracic Expert Panel consists of radiologists, respirologists, emergency and family physicians, a patient advisor, and an epidemiologist/guideline methodologist. After developing a list of 24 clinical/diagnostic scenarios, a rapid scoping review was undertaken to identify systematically produced referral guidelines that provide recommendations for one or more of these clinical/diagnostic scenarios. Recommendations from 30 guidelines and contextualization criteria in the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) for guidelines framework were used to develop 48 recommendation statements across the 24 scenarios. This guideline presents the methods of development and the referral recommendations for screening/asymptomatic individuals, non-specific chest pain, hospital admission for non-thoracic conditions, long-term care admission, routine pre-operative imaging, post-interventional chest procedure, upper respiratory tract infection, acute exacerbation of asthma, acute exacerbation of chronic obstructive pulmonary disease, suspect pneumonia, pneumonia follow-up, immunosuppressed patient with respiratory symptoms/febrile neutropenia, chronic cough, suspected pneumothorax (non-traumatic), clinically suspected pleural effusion, hemoptysis, chronic dyspnea of non-cardiovascular origin, suspected interstitial lung disease, incidental lung nodule, suspected mediastinal lesion, suspected mediastinal lymphadenopathy, and elevated diaphragm on chest radiograph.

Integration and Application of Radiologic Patterns From Clinical Practice Guidelines on Idiopathic Pulmonary Fibrosis and Fibrotic Hypersensitivity Pneumonitis.

BACKGROUND: Clinical practice guidelines separately describe radiologic patterns of usual interstitial pneumonia (UIP) and fibrotic hypersensitivity pneumonitis (fHP), without direction on whether or how to apply these approaches concurrently within a single patient. RESEARCH QUESTION: How can we integrate guideline-defined radiologic patterns to diagnose interstitial lung disease (ILD) and what are the pitfalls associated with described patterns that require reassessment in future guidelines? STUDY DESIGN AND METHODS: Patients from the Canadian Registry for Pulmonary Fibrosis underwent detailed reevaluation in standardized multidisciplinary discussion. CT scan features were quantified by chest radiologists masked to clinical data, and guideline-defined patterns were assigned. Clinical data then were provided to the radiologist and an ILD clinician, who jointly determined the leading diagnosis. RESULTS: Clinical-radiologic diagnosis in 1,593 patients was idiopathic pulmonary fibrosis (IPF) in 26%, fHP in 12%, connective tissue disease-associated ILD (CTD-ILD) in 34%, idiopathic pneumonia with autoimmune features in 12%, and unclassifiable ILD in 10%. Typical and probable UIP patterns corresponded to a diagnosis of IPF in 66% and 57% of patients, respectively. Typical fHP pattern corresponded to an fHP clinical diagnosis in 65% of patients, whereas compatible fHP was nonspecific and associated with CTD-ILD or IPAF in 48% of patients. No pattern ruled out CTD-ILD. Gas trapping affecting > 5% of lung parenchyma on expiratory imaging was an important feature broadly separating compatible and typical fHP from other patterns (sensitivity, 0.77; specificity, 0.91). INTERPRETATION: An integrated approach to guideline-defined UIP and fHP patterns is feasible and supports > 5% gas trapping as an important branch point. Typical or probable UIP and typical fHP patterns have moderate predictive values for a corresponding diagnosis of IPF and fHP, although occasionally confounded by CTD-ILD; compatible fHP is nonspecific.

Cystic Primary Lung Cancer: Evolution of Computed Tomography Imaging Morphology Over Time.

PURPOSE: Primary lung cancers associated with cystic airspaces are increasingly being recognized; however, there is a paucity of data on their natural history. We aimed to evaluate the prevalence, pathologic, and imaging characteristics of cystic lung cancer in a regional thoracic surgery center with a focus on the evolution of computed tomography morphology over time. MATERIALS AND METHODS: Consecutive patients referred for potential surgical management of primary lung cancer between January 2016 and December 2018 were included. Clinical, imaging, and pathologic data were collected at the time of diagnosis and at the time of the oldest computed tomography showing the target lesion. Descriptive analysis was carried out. RESULTS: A total of 441 cancers in 431 patients (185 males, 246 females), median age 69.6 years (interquartile range: 62.6 to 75.3 y), were assessed. Overall, 41/441 (9.3%) primary lung cancers were cystic at the time of diagnosis. The remaining showed solid (67%), part-solid (22%), and ground-glass (2%) morphologies. Histopathology of the cystic lung cancers at diagnosis included 31/41 (76%) adenocarcinomas, 8/41 (20%) squamous cell carcinomas, 1/41 (2%) adenosquamous carcinoma, and 1/41 (2%) unspecified non-small cell lung carcinoma. Overall, 8/34 (24%) cystic cancers at the time of diagnosis developed from different morphologic subtype precursor lesions, while 8/34 (24%) cystic precursor lesions also transitioned into part-solid or solid cancers at the time of diagnosis. CONCLUSIONS: This study demonstrates that cystic airspaces within lung cancers are not uncommon, and may be seen transiently as cancers evolve. Increased awareness of the spectrum of cystic lung cancer morphology is important to improve diagnostic accuracy and lung cancer management.

The Impact of Implementing 24/7 Cardiac CTA Interpretation in the Emergency Department on Patient Care: Retrospective Analysis of a Single-Center Experience.

OBJECTIVE. The objective of our study was to provide insight on the diagnostic validity of cardiac CTA (CCTA) to identify obstructive coronary artery disease (CAD) and patients who require urgent intervention, compared with those who require same-admission coronary catheterization (CC), and to help elucidate the necessity of a 24/7 CCTA service. MATERIALS AND METHODS. We retrospectively reviewed 658 consecutive CCTA examinations performed of emergency department (ED) patients who presented with acute chest pain from October 1, 2013, to February 28, 2018. Patients were categorized by CAD severity on CCTA. Using same-admission CC as the reference standard, we assessed CCTA's validity to identify obstructive disease using PPV, NPV, sensitivity, and specificity and CCTA's validity to identify patients who require urgent intervention. The added value of the CCTA findings of subendocardial hypoattenuation and wall motion abnormality was evaluated. CCTA examinations were categorized on the basis of the time of day when scanning was performed. RESULTS. The PPV, NPV, and sensitivity of CCTA to diagnose obstructive CAD were 0.87, 0.79, and 0.95, respectively. Nine percent of the scanned patients underwent percutaneous coronary intervention (PCI) or were referred for urgent coronary artery bypass grafting (CABG). The presence of obstructive CAD on CCTA has a PPV of 0.73 to identify patients deemed to be at higher acute coronary syndrome (ACS) risk to warrant urgent PCI or CABG. Wall motion abnormality increased the PPV to 1.0; subendocardial attenuation increased the PPV to 0.9. The NPV and sensitivity were 0.89 and 0.97, respectively. Of the CCTA examinations, 54% were performed outside regular working hours. Of the patients who received urgent interventions, 62% underwent CCTA examinations performed outside regular working hours. CONCLUSION. CCTA provides high correlation with CC, helps identify individuals with high ACS risk, and is further strengthened by functional analysis; 24/7 CCTA service is warranted.

Chronic Lung Allograft Dysfunction: Review of CT and Pathologic Findings.

Chronic lung allograft dysfunction (CLAD) is the most common cause of mortality in lung transplant recipients after the 1st year of transplantation. CLAD has traditionally been classified into two distinct obstructive and restrictive forms: bronchiolitis obliterans syndrome and restrictive allograft syndrome. However, CLAD may manifest with a spectrum of imaging and pathologic findings and a combination of obstructive and restrictive physiologic abnormalities. Although the initial CT manifestations of CLAD may be nonspecific, the progression of findings at follow-up should signal the possibility of CLAD and may be present on imaging studies prior to the development of functional abnormalities of the lung allograft. This review encompasses the evolution of CT findings in CLAD, with emphasis on the underlying pathogenesis and pathologic condition, to enhance understanding of imaging findings. The purpose of this article is to familiarize the radiologist with the initial and follow-up CT findings of the obstructive, restrictive, and mixed forms of CLAD, for which early diagnosis and treatment may result in improved survival. Supplemental material is available for this article. © RSNA, 2021.

Canadian Society of Thoracic Radiology/Canadian Association of Radiologists Clinical Practice Guidance for Non-Vascular Thoracic MRI.

Historically thoracic MRI has been limited by the lower proton density of lung parenchyma, cardiac and respiratory motion artifacts and long acquisition times. Recent technological advancements in MR hardware systems and improvement in MR pulse sequences have helped overcome these limitations and expand clinical opportunities for non-vascular thoracic MRI. Non-vascular thoracic MRI has been established as a problem-solving imaging modality for characterization of thymic, mediastinal, pleural chest wall and superior sulcus tumors and for detection of endometriosis. It is increasingly recognized as a powerful imaging tool for detection and characterization of lung nodules and for assessment of lung cancer staging. The lack of ionizing radiation makes thoracic MRI an invaluable imaging modality for young patients, pregnancy and for frequent serial follow-up imaging. Lack of familiarity and exposure to non-vascular thoracic MRI and lack of consistency in existing MRI protocols have called for clinical practice guidance. The purpose of this guide, which was developed by the Canadian Society of Thoracic Radiology and endorsed by the Canadian Association of Radiologists, is to familiarize radiologists, other interested clinicians and MR technologists with common and less common clinical indications for non-vascular thoracic MRI, discuss the fundamental imaging findings and focus on basic and more advanced MRI sequences tailored to specific clinical questions.

Radiological Society of North America (RSNA) Expert Consensus Statement Related to Chest CT Findings in COVID-19 Versus CO-RADS: Comparison of Reporting System Performance Among Chest Radiologists and End-User Preference.

PURPOSE: The RSNA expert consensus statement and CO-RADS reporting system assist radiologists in describing lung imaging findings in a standardized manner in patients under investigation for COVID-19 pneumonia and provide clarity in communication with other healthcare providers. We aim to compare diagnostic performance and inter-/intra-observer among chest radiologists in the interpretation of RSNA and CO-RADS reporting systems and assess clinician preference. METHODS: Chest CT scans of 279 patients with suspected COVID-19 who underwent RT-PCR testing were retrospectively and independently examined by 3 chest radiologists who assigned interpretation according to the RSNA and CO-RADS reporting systems. Inter-/intra-observer analysis was performed. Diagnostic accuracy of both reporting systems was calculated. 60 clinicians participated in a survey to assess end-user preference of the reporting systems. RESULTS: Both systems demonstrated almost perfect inter-observer agreement (Fleiss kappa 0.871, P < 0.0001 for RSNA; 0.876, P < 0.0001 for CO-RADS impressions). Intra-observer agreement between the 2 scoring systems using the equivalent categories was almost perfect (Fleiss kappa 0.90-0.92, P < 0.001). Positive predictive values were high, 0.798-0.818 for RSNA and 0.891-0.903 CO-RADS. Negative predictive value were similar, 0.573-0.585 for RSNA and 0.573-0.58 for CO-RADS. Specificity differed between the 2 systems, 68-73% for CO-RADS and 52-58% for RSNA with superior specificity of CO-RADS. Of 60 survey participants, the majority preferred the RSNA reporting system rather than CO-RADS for all options provided (66.7-76.7%; P < 0.05). CONCLUSIONS: RSNA and CO-RADS reporting systems are consistent and reproducible with near perfect inter-/intra-observer agreement and excellent positive predictive value. End-users preferred the reporting language in the RSNA system.

RSNA Expert Consensus Statement on Reporting Chest CT Findings Related to COVID-19: Interobserver Agreement Between Chest Radiologists.

PURPOSE: To assess the interobserver variability between chest radiologists in the interpretation of the Radiological Society of North America (RSNA) expert consensus statement reporting guidelines in patients with suspected coronavirus disease 2019 (COVID-19) pneumonia in a setting with limited reverse transcription polymerase chain reaction testing availability. METHODS: Chest computed tomography (CT) studies in 303 consecutive patients with suspected COVID-19 were reviewed by 3 fellowship-trained chest radiologists. Cases were assigned an impression of typical, indeterminate, atypical, or negative for COVID-19 pneumonia according to the RSNA expert consensus statement reporting guidelines, and interobserver analysis was performed. Objective CT features associated with COVID-19 pneumonia and distribution of findings were recorded. RESULTS: The Fleiss kappa for all observers was almost perfect for typical (0.815), atypical (0.806), and negative (0.962) COVID-19 appearances (P < .0001) and substantial (0.636) for indeterminate COVID-19 appearance (P < .0001). Using Cramer V analysis, there were very strong correlations between all radiologists' interpretations, statistically significant for all (typical, indeterminate, atypical, and negative) COVID-19 appearances (P < .001). Objective CT imaging findings were recorded in similar percentages of typical cases by all observers. CONCLUSION: The RSNA expert consensus statement on reporting chest CT findings related to COVID-19 demonstrates substantial to almost perfect interobserver agreement among chest radiologists in a relatively large cohort of patients with clinically suspected COVID-19. It therefore serves as a reliable reference framework for radiologists to accurately communicate their level of suspicion based on the presence of evidence-based objective findings.

Role of a Regional Multidisciplinary Conference in the Diagnosis of Interstitial Lung Disease.

RATIONALE: The interstitial lung disease (ILD) specialists in Vancouver participate in a multidisciplinary discussion (MDD) that is primarily used internally for patients seen by these specialists. The MDD is also used remotely (externally) by general pulmonologists to increase access to this service. OBJECTIVES: To describe the impact of an MDD on the diagnosis and management of ILD in these two patient cohorts, and to report the satisfaction of referring pulmonologists with this service. METHODS: This retrospective cross-sectional study included patients who underwent MDD review between March 2014 and June 2017. Data were extracted from standardized MDD records and comparisons were made between the internal and external ILD cohorts. Pulmonologists who used the external review service completed an anonymous survey addressing their satisfaction with components of the MDD. RESULTS: The 209 internal patients and 91 external patients had similar clinical characteristics. MDD review led to a change in diagnosis in 40% of patients, including 36% of internal patients and 48% of external patients (P = 0.04). For patients without a working diagnosis, 44% were provided a confident ILD diagnosis following MDD, including 78% of patients with a surgical lung biopsy and 37% of patients without a surgical lung biopsy (P < 0.001). After MDD review, treatment was started in 45% of patients on no ILD therapy, and treatment was changed in 45% of patients on ILD therapy. Overall, 93% of the 14 respondents (out of 16 surveyed) were very or somewhat satisfied with the MDD external review service. CONCLUSIONS: Similar to previous publications, our study suggests an important role of MDD in the diagnosis and management of ILD, and further demonstrates that MDD of external patients is a viable service that allows greater and more rapid access to ILD expertise.

Evaluation of the proximal coronary arteries in suspected pulmonary embolism: diagnostic images in 51% of patients using non-gated, dual-source CT pulmonary angiography.

PURPOSE: This retrospective study reports the frequency and severity of coronary artery motion on dual-source high-pitch (DSHP), conventional pitch single-source (SS), and dual-source dual-energy (DE) CT pulmonary angiography (CTPA) studies. METHODS: Two hundred eighty-eight consecutive patients underwent CTPA scans for suspected pulmonary embolism between September 1, 2013 and January 31, 2014. One hundred ninety-four at DSHP scans, 57 SS scans, and 37 DE scans were analyzed. Coronary arteries were separated into nine segments, and coronary artery motion was qualitatively scored using a scale from 1 to 4 (non-interpretable to diagnostic with no motion artifacts). Signal intensity, noise, and signal to noise ratio (SNR) of the aorta, main pulmonary artery, and paraspinal muscles were also assessed. RESULTS: DSHP CTPA images had significantly less coronary artery motion, with 30.1% of coronary segments being fully evaluable compared to 4.2% of SS segments and 7.9% of DE segments (p < 0.05 for all comparisons). When imaging with DSHP, the proximal coronary arteries were more frequently evaluable than distal coronary arteries (51% versus 11.3%, p < 0.001). Without ECG synchronization and heart rate control, the distal left anterior descending coronary artery and mid right coronary artery remain infrequently interpretable (7% and 9%, respectively) on DSHP images. CONCLUSIONS: DSHP CTPA decreases coronary artery motion artifacts and allows for full evaluation of the proximal coronary arteries in 51% of cases. The study highlights the increasing importance of proximal coronary artery review when interpreting CTPA for acute chest pain.

Histopathologic findings in lung biopsies from patients with primary biliary cholangitis.

Primary biliary cholangitis (PBC) is a progressive autoimmune disease of the liver causing destruction of intrahepatic bile ducts, associated with lymphocytic and granulomatous inflammation. PBC has been associated with many extrahepatic manifestations including interstitial lung disease. However, comprehensive pulmonary histopathology in PBC has not been well documented. Sixteen PBC patients who underwent lung biopsies were identified from surgical pathology files in three institutions. Histopathologic review was performed. Patient age ranged 41 to 79 years (median 55 years) and 15 patients (94%) were women. Specimens consisted of lobectomy (n = 1), surgical biopsies (n = 12), transthoracic needle biopsy (n = 1) and transbronchial biopsy (n = 2). Fifteen of 16 (94%) cases showed lymphocytic inflammation, mainly localized to peribronchiolar stroma and alveolar septa. Thirteen (81%) cases revealed non-necrotizing granulomas, most of which were poorly formed, reminiscent of those seen in liver biopsies from PBC patients. Six cases also showed eosinophilic infiltrates. Organizing pneumonia was seen in 7 cases. Four cases showed diffuse interstitial fibrosis with nonspecific interstitial pneumonia and usual interstitial pneumonia patterns. One patient underwent lobectomy for a mass lesion and was diagnosed with light chain deposition disease with underlying κ-restricted extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue. In summary, PBC-associated histopathologic changes in the lung include lymphocytic inflammation predominantly around small airways and non-necrotizing granulomas in multiple compartments of lung tissue, which parallel PBC-associated histopathology in liver biopsies, often associated with other common patterns of diffuse lung disease.

Pleural amyloidosis imitating pleural malignancy.

CT chest performed to investigate dyspnea and malaise in an 83 year old man demonstrated bilateral circumferential pleural thickening highly suspicious for pleural mesothelioma or metastatic pleural malignancy. Histopathology of a subsequent pleural biopsy returned a diagnosis of pleural amyloid. This case identifies pleural amyloid as a rare differential consideration for diffuse pleural thickening; the difficulties in distinguishing pleural amyloid from pleural malignancy are highlighted.

Dual-source CT in blunt trauma patients: elimination of diaphragmatic motion using high-pitch spiral technique.

The purpose of this study was to compare diaphragmatic motion on dual-source high-pitch (DS-HP) and conventional single-source (SS) CT scans in trauma patients. Seventy-five consecutive trauma patients who presented to a level one trauma center over a 6-month period were scanned with a standardized whole body trauma CT protocol including both DS-HP chest (pitch = 2.1-2.5) and SS abdominal CT scans. Subjective analysis of diaphragmatic motion was performed by two readers using a four-point motion scale in seven regions of the diaphragm on coronal and axial slices. An overall confidence score to exclude a diaphragmatic tear was determined (1 to 10, 10: completely confident and 1: impossible to exclude). Wilcoxon rank sum tests were used for statistical analysis, and p < 0.05 was considered significant. Mean confidence score of 9.85 for DS-HP was significantly better than the mean score of 7.66 for SS images (p < 0.0001). Diaphragmatic motion scores and subjective diaphragmatic motion artifact on coronal and axial images were significantly better for DS-HP images in all areas when compared individually (p < 0.0001) and overall (p < 0.0001). Regions of DS-HP (99.2 %) were diagnostic, whereas only 87.0 % % regions on SS were. Complete agreement of motion scores was present in 92 % of cases, with moderate overall agreement for confidence to exclude a diaphragmatic tear (κ = 0.45). Dual-source high-pitch CT scanning is advantageous as it allows for significantly better evaluation of diaphragmatic structures by minimizing motion artifacts on images of freely breathing trauma patients.

Fibrosing Bronchiolitis Evolving from Infectious or Inhalational Acute Bronchiolitis. A Reversible Lesion.

RATIONALE: Occasional cases of bronchiolitis show pathologic features somewhat suggestive of constrictive bronchiolitis, but with granulation tissue plugs that variably occlude the lumen in a pattern more typical of organizing pneumonia. These cases are poorly defined in the literature and the course of patients with this pattern of disease is unclear. OBJECTIVE: To describe an uncommon and potentially treatable pattern of acute bronchiolitis that has been termed fibrosing bronchiolitis. MAIN RESULTS: We report three patients with respiratory failure and acute onset of probable infectious or inhalational bronchiolitis that was characterized by centrilobular nodules and a variable tree-in-bud appearance on computed tomography. All patients showed an uncommon pattern of bronchiolitis on surgical lung biopsy. The pathologic abnormalities were confined to the bronchioles and consisted of reepithelialized, partially collagenized and variably polypoid plugs of granulation tissue that narrowed the bronchiolar lumens. All three patients improved dramatically on immunosuppressive therapy. CONCLUSIONS: These cases of fibrosing bronchiolitis represent an uncommon pattern of acute bronchiolitis that is reversible if detected at an early stage. Early recognition and treatment may prevent development of permanent bronchiolar fibrosis.

Thoracic computed tomographic manifestations of tuberous sclerosis in adults.

The purpose of this article is to illustrate the various manifestations that can be encountered on thoracic computed tomography of tuberous sclerosis in adults. The pulmonary findings include lymphangioleiomyomatosis and multifocal micronodular pneumocyte hyperplasia. The extrapulmonary manifestations are divided into cardiac, vascular, mediastinal, osseous, and upper abdominal findings.

Vancouver simplified grading system with computed tomographic angiography for blunt aortic injury.

OBJECTIVE: Delineation of blunt aortic injury by computed tomographic angiography guides management of this potentially fatal injury. Two existing grading systems are problematic to apply and not linked to outcomes. A simplified computed tomographic angiography-based grading system, linked to clinical outcomes, was developed, and feasibility and reliability were evaluated. METHODS: Retrospective review was performed of all blunt aortic injury cases presenting to a single provincial quaternary referral center designated for blunt aortic injury management between 2001 and 2009. Management, associated injuries, hospital survival, and cause of death were determined. Initial computed tomographic angiography was reviewed, and injuries were graded according to the new Vancouver simplified grading system by 2 study authors. Three additional trauma radiologists then graded the aortic injuries with the 2 existing systems and the simplified system. Interrater reliability was determined. RESULTS: Forty-eight patients were identified. Two had minimal aortic injury (grade I), 7 had an intimal flap larger than 1 cm (grade II), 32 had traumatic pseudoaneurysm (grade III), 6 had active contrast extravasation (grade IV), and 1 could not be rated. Survivals were 100%, 90%, and 33% for grades I and II, III, and IV, respectively. Of grade III injuries, 14% were medically managed, 68% repaired endovascularly, and 18% repaired with open surgery. Interrater correlation was best with the simplified score, with only 0.5% of cases unable to be classified. CONCLUSIONS: The Vancouver simplified blunt aortic injury grading system is easy to use and correlates with clinical outcomes. Prospective external validation is required.

Smoking-related emphysema and interstitial lung diseases.

Smoking-related illnesses contribute to a large number of deaths in the industrialized world and their treatment comprises a substantial percentage of total healthcare dollars. The most common and most well-known smoking-related illnesses include chronic obstructive pulmonary disease, bronchogenic carcinoma, and ischemic heart disease. However, the role of cigarette smoking in the pathogenesis of other lung diseases is becoming increasingly apparent. Knowledge of both the histologic and radiographic manifestations of smoking-related lung disease is important to the radiologist as imaging findings can be nonspecific. Finally, correlation of imaging and clinical information may obviate the need for open lung biopsy.