Managing Incidental Findings on Thoracic CT: Lung Findings. A White Paper of the ACR Incidental Findings Committee.

The ACR Incidental Findings Committee presents recommendations for managing incidentally detected lung findings on thoracic CT. The Chest Subcommittee is composed of thoracic radiologists who endorsed and developed the provided guidance. These recommendations represent a combination of current published evidence and expert opinion and were finalized by informal iterative consensus. The recommendations address commonly encountered incidental findings in the lungs and are not intended to be a comprehensive review of all pulmonary incidental findings. The goal is to improve the quality of care by providing guidance on management of incidentally detected thoracic findings.

ACR Appropriateness Criteria® Intensive Care Unit Patients.

Chest radiography is the most frequent and primary imaging modality in the intensive care unit (ICU), given its portability, rapid image acquisition, and availability of immediate information on the bedside preview. Due to the severity of underlying disease and frequent need of placement of monitoring devices, ICU patients are very likely to develop complications related to underlying disease process and interventions. Portable chest radiography in the ICU is an essential tool to monitor the disease process and the complications from interventions; however, it is subject to overuse especially in stable patients. Restricting the use of chest radiographs in the ICU to only when indicated has not been shown to cause harm. The emerging role of bedside point-of-care lung ultrasound performed by the clinicians is noted in the recent literature. The bedside lung ultrasound appears promising but needs cautious evaluation in the future to determine its role in ICU patients. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Hemoptysis.

Hemoptysis, the expectoration of blood, ranges in severity from nonmassive to massive. This publication reviews the literature on the imaging and treatment of hemoptysis. Based on the literature, the imaging recommendations for massive hemoptysis are both a chest radiograph and CT with contrast or CTA with contrast. Bronchial artery embolization is also recommended in the majority of cases. In nonmassive hemoptysis, both a chest radiograph and CT with contrast or CTA with contrast is recommended. Bronchial artery embolization is becoming more commonly utilized, typically in the setting of failed medical therapy. Recurrent hemoptysis, defined as hemoptysis that recurs following initially successful cessation of hemoptysis, is best reassessed with a chest radiograph and either CT with contrast or CTA with contrast. Bronchial artery embolization is increasingly becoming the treatment of choice in recurrent hemoptysis, with the exception of infectious causes such as in cystic fibrosis. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Establishing and Maintaining Research Integrity at Academic Institutions: Challenges and Opportunities.

Integrity and trust are essential attributes of medical researchers. Research misconduct represents clear and present dangers to academic institutions and their faculty, residents, students, and staff. To achieve and maintain public trust, medical researchers must achieve and maintain research integrity. To do so requires synchronicity and collaboration between and within academic institutions. Substantial failures to maintain research integrity by institutional leadership will lead to increasing demands to do so from the funding organizations and the general public. This, in turn, will lead to avoidable consequences of substantial penalties, financial and otherwise, adverse publicity, and reputational damage. Researchers must self-regulate to avoid pitfalls, including those created by changes in the medical care delivery system that have decreased the influence of health care providers and increased the influence of outside legal and business interests. Our common goal should be to return public trust in our research enterprise that has done so much good for so many, but requires the establishment and maintenance of vigilance to establish and maintain research integrity.

Inter-observer agreement in identifying traction bronchiectasis on computed tomography: its improvement with the use of the additional criteria for chronic fibrosing interstitial pneumonia.

PURPOSE: To assess inter-observer variability in identifying traction bronchiectasis on computed tomography (CT) using additional criteria for chronic fibrosing interstitial pneumonia. METHODS: Seven experts categorized CT image set representing 39 patients into three groups on the basis of the presence of traction bronchiectasis, using a three-point scale: 3-definitely/probably yes; 2-possibly yes; and 1-definitely/probably no. This scale served as a reference standard. The image set included cases of chronic fibrosing interstitial pneumonia, non-interstitial lung disease, and difficult-to-determine cases. Forty-eight observers similarly assessed the same image set, first according to the Fleischner Society definition, and second with additional criteria, in which traction bronchiectasis was observed exclusively in chronic fibrosing interstitial pneumonia. The agreement level between the reference standard and each observer's evaluation in each session was calculated using weighted kappa values which were compared between the two sessions using a paired t test. RESULTS: The mean weighted kappa value for all observers was significantly higher in the second reading session (mean 0.75) than in the first reading session (mean 0.62) (p < 0.001). CONCLUSION: Inter-observer agreement in identifying traction bronchiectasis improves when using the additional criteria which specify chronic fibrosing interstitial pneumonia as the underlying disease.

Micronodules Detected on Computed Tomography During the National Lung Screening Trial: Prevalence and Relation to Positive Studies and Lung Cancer.

INTRODUCTION: In the National Lung Screening Trial (NLST) all cases with a 4-mm nodule (micronodule) and no other findings were classified as a negative study. The prevalence and malignant potential of micronodules in the NLST is evaluated to understand if this classification was appropriate. METHODS AND MATERIALS: In the NLST a total of 53,452 participants were enrolled with 26,722 undergoing low-dose computed tomography (CT) screening. To determine whether a micronodule developed into a lung cancer, a list from the NLST database of those participants who developed lung cancer and had a micronodule recorded was selected. The CT images of this subset were reviewed by experienced, fellowship-trained thoracic radiologists (R.F.M., C.C., P.M.B., and D.R.A.), all of whom participated as readers in the NLST. RESULTS: There were 26,722 participants who underwent CT in the NLST, of which 11,326 (42%) participants had at least one CT with a micronodule. Five thousand five hundred sixty (49%) of these participants had at least one positive CT examination, of which 409 (3.6%) subsequently were diagnosed with lung cancer. Of the 409 lung cancer cases with a micronodule recorded, there were 13 cases in which a micronodule developed into lung cancer. Considering the 13 cases, they represent 1.2% (13 of 1089) of the lung cancers diagnosed in the CT arm of the NLST and 0.11% (13 of 11,326) of the total micronodule cases. Additionally they represent 0.23% (13 of 5560) of the micronodule and at least one positive CT examination cases and 3.2% (13 of 409) of the micronodule cases diagnosed with lung cancer. The average size of the nodule at baseline (recorded as maximum diameter by perpendicular diameter) was 3.0 × 2.5 mm (ranges 2 x 4 mm and 2 x 4 mm) and at the positive CT the nodule was 11.1 × 8.6 mm (ranges, 6 x 20 mm and 5 x 14 mm); a difference of average change in size of 8.1 × 6.1 mm. The average number of days from first CT with a micronodule recorded to positive CT was 459 days (range, 338 - 723 days), the mean time from first CT with micronodule to lung cancer diagnosis was 617 days (range, 380 - 1140 days) and the mean time from positive CT to lung cancer diagnosis was 160 days (range, 18 - 417 days). Histologically, there was one small cell carcinoma and 12 non-small cell with stages of IA in 8 (62%), stage IB in 2 (15%), and 1 each stage IIIA, IIIB, and IV. The overall survival of NSCLC cases with a micronodule was not significantly different than the survival of the CT subset diagnosed with NSCL (p = 0.36). CONCLUSIONS: Micronodules are common among lung cancer-screened participants and are capable of developing into lung cancer; however, following micronodules by annual CT screening surveillance is appropriate and does not impact overall survival or outcome.

ACR Appropriateness Criteria® Rib Fractures.

Rib fractures are the most common thoracic injury after minor blunt trauma. Although rib fractures can produce significant morbidity, the diagnosis of injuries to underlying organs is arguably more important as these complications are likely to have the most significant clinical impact. Isolated rib fractures have a relatively low morbidity and mortality and treatment is generally conservative. As such, evaluation with standard chest radiographs is usually sufficient for the diagnosis of rib fractures, and further imaging is generally not appropriate as there is little data that undiagnosed isolated rib fractures after minor blunt trauma affect management or outcomes. Cardiopulmonary resuscitation frequently results in anterior rib fractures and chest radiographs are usually appropriate (and sufficient) as the initial imaging modality in these patients. In patients with suspected pathologic fractures, chest CT or Tc-99m bone scans are usually appropriate and complementary modalities to chest radiography based on the clinical scenario. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Longitudinal Follow-up of Patients With Tracheobronchomalacia After Undergoing Tracheobronchoplasty: Computed Tomography Findings and Clinical Correlation.

PURPOSE: The purpose of this study was to evaluate intermediate and long-term changes in expiratory tracheal collapsibility by computed tomography (CT) in patients with tracheobronchomalacia following surgical treatment with tracheobronchoplasty and to correlate CT findings with clinical findings. MATERIALS AND METHODS: Between 2003 and 2016, 18 patients with tracheobronchomalacia underwent tracheobronchoplasty and were imaged preoperatively and postoperatively at both intermediate and long-term intervals. Imaging included end-inspiratory and dynamic expiratory phase scans. The cross-sectional area of the airway lumen was measured at 2 standard levels (1 cm above the aortic arch and carina). These measurements were used to calculate % collapsibility. Clinical findings recorded included a questionnaire on symptomatology and a 6-minute walk test. RESULTS: Before surgery, expiratory collapsibility of the upper trachea was 72%±25% (mean±SD) and that of the lower trachea was 68%±22%. On intermediate follow-up (mean, 1.5 y), collapsibility significantly decreased to 37%±21% at the upper trachea and 35%±19% at the lower trachea (P<0.001). On long-term follow-up (mean, 6 y), collapsibility increased to 51%±20% at the upper trachea and 47%±17% at the lower trachea and was significantly worse than on intermediate follow-up (P=0.002). However, collapsibility on long-term follow-up remained significantly lower than preoperative collapsibility (P=0.015). Clinical findings showed a similar trend as quantitative CT measurements. CONCLUSION: Expiratory tracheal collapsibility substantially decreases after tracheobronchoplasty on intermediate follow-up. At long-term follow-up, tracheal collapsibility shows a modest increase, but remains significantly lower than the preoperative baseline. Quantitative measurements from dynamic CT have the potential to play an important role as imaging biomarkers for assessing response to tracheobronchoplasty.

ACR Appropriateness Criteria® Lung Cancer Screening.

Lung cancer remains the leading cause of cancer death in both men and women. Smoking is the single greatest risk factor for the development of lung cancer. For patients between the age of 55 and 80 with 30 or more pack years smoking history who currently smoke or who have quit within the last 15 years should undergo lung cancer screening with low-dose CT. In patients who do not meet these criteria but who have additional risk factors for lung cancer, lung cancer screening with low-dose CT is controversial but may be appropriate. Imaging is not recommended for lung cancer screening of patient younger than 50 years of age or patients older than 80 years of age or patients of any age with less than 20 packs per year history of smoking and no additional risk factor (ie, radon exposure, occupational exposure, cancer history, family history of lung cancer, history of COPD, or history of pulmonary fibrosis). The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Managing Incidental Findings on Thoracic CT: Mediastinal and Cardiovascular Findings. A White Paper of the ACR Incidental Findings Committee.

The ACR Incidental Findings Committee presents recommendations for managing incidentally detected mediastinal and cardiovascular findings found on CT. The Chest Subcommittee was composed of thoracic radiologists who developed the provided guidance. These recommendations represent a combination of current published evidence and expert opinion and were finalized by informal iterative consensus. The recommendations address the most commonly encountered mediastinal and cardiovascular incidental findings and are not intended to be a comprehensive review of all incidental findings associated with these compartments. Our goal is to improve the quality of care by providing guidance on how to manage incidentally detected thoracic findings.

Cine MRI of Tracheal Dynamics in Healthy Volunteers and Patients With Tracheobronchomalacia.

OBJECTIVE: Bronchoscopy and MDCT are routinely used to assess tracheobronchomalacia (TBM). Recently, dynamic MRI (cine MRI) has been proposed as a radiation-free alternative to MDCT. In this study, we tested cine MRI assessment of airway dynamics during various breathing conditions and compared cine MRI and MDCT measurements in healthy volunteers and patients with suspected TBM. CONCLUSION: Cine MRI was found to be a technically feasible alternative to MDCT for assessing central airway dynamics.

Differentiating between Subsolid and Solid Pulmonary Nodules at CT: Inter- and Intraobserver Agreement between Experienced Thoracic Radiologists.

PURPOSE: To quantify the reproducibility and accuracy of experienced thoracic radiologists in differentiating between subsolid and solid pulmonary nodules at CT. MATERIALS AND METHODS: The institutional review board of Beth Israel Deaconess Medical Center approved this multicenter study. Six thoracic radiologists, with a mean of 21 years of experience in thoracic radiology (range, 17-22 years), selected images of 10 solid and 10 subsolid nodules to create a database of 120 nodules; this selection served as the reference standard. Each radiologist then interpreted 120 randomly ordered nodules in two different sessions that were separated by a minimum of 3 weeks. The radiologists classified whether or not each nodule was subsolid. Inter- and intraobserver agreement was assessed with a κ statistic. The number of correct classifications was calculated and correlated with nodule size by using Bland-Altman plots. The relationship between disagreement and nodule morphologic characteristics was analyzed by calculating the intraclass correlation coefficient. RESULTS: Interobserver agreement (κ) was 0.619 (range, 0.469-0.745; 95% confidence interval (CI): 0.576, 0.663) and 0.670 (range, 0.440-0.839; 95% CI: 0.608, 0.733) for interpretation sessions 1 and 2, respectively. Intraobserver agreement (κ) was 0.792 (95% CI: 0.750, 0.833). Averaged for interpretation sessions, correct classification was achieved by all radiologists for 58% (70 of 120) of nodules. Radiologists agreed with their initial determination (the reference standard) in 77% of cases (range, 45%-100%). Nodule size weakly correlated with correct classification (long axis: Spearman rank correlation coefficient, rs = 0.161 and P = .049; short axis: rs = 0.128 and P = .163). CONCLUSION: The reproducibility and accuracy of thoracic radiologists in classifying whether or not a nodule is subsolid varied in the retrospective study. This inconsistency may affect surveillance recommendations and prognostic determinations.

Screening for Lung Cancer With Low-Dose Computed Tomography: Grand Rounds Discussion From the Beth Israel Deaconess Medical Center.

In December 2013, the U.S. Preventive Services Task Force recommended screening for lung cancer with low-dose computed tomography (LDCT) for selected current and former smokers. The Task Force based the recommendation primarily on the results of the NLST (National Lung Screening Trial). In this trial, patients randomly assigned to LDCT screening for 3 years had lower rates of both lung cancer-specific mortality and all-cause mortality (relative risk reduction, 6.7% [95% CI, 1.2% to 13.6%]; absolute risk reduction, 0.46% [CI, 0% to 0.9%]). Clinicians and health systems confront questions and challenges as they begin to implement lung cancer screening. This paper summarizes a conference during which an internist and a radiologist discuss the application of the Task Force recommendation to an individual patient.