Lessons Learned from Peer Learning Conference in Cardiothoracic Radiology.

Medical errors may lead to patient harm and may also have a devastating effect on medical providers, who may suffer from guilt and the personal impact of a given error (second victim experience). While it is important to recognize and remedy errors, it should be done in a way that leads to long-standing practice improvement and focuses on systems-level opportunities rather than in a punitive fashion. Traditional peer review systems are score based and have some undesirable attributes. The authors discuss the differences between traditional peer review systems and peer learning approaches and offer practical suggestions for transitioning to peer learning conferences. Peer learning conferences focus on learning opportunities and embrace errors as an opportunity to learn. The authors also discuss various types and sources of errors relevant to the practice of radiology and how discussions in peer learning conferences can lead to widespread system improvement. In the authors' experience, these strategies have resulted in practice improvement not only at a division level in radiology but in a broader multidisciplinary setting as well. The online slide presentation from the RSNA Annual Meeting is available for this article. ©RSNA, 2022.

Distinguishing acute from chronic aortic dissections using CT imaging features.

The aim was to compare computed tomography (CT) features in acute and chronic aortic dissections (AADs and CADs) and determine if a certain combination of imaging features was reliably predictive of the acute versus chronic nature of disease in individual patients. Consecutive patients with aortic dissection and a chest CT scan were identified, and 120 CT scans corresponding to 105 patients were reviewed for a variety of imaging features. Statistical tests assessed for differences in the frequency of these features. A predictive model was created and tested on an additional 120 CT scans from 115 patients. Statistically significant features of AAD included periaortic confluent soft tissue opacity, curved dissection flap, and highly mobile dissection flap, and features of CAD included thick dissection flap, false lumen (FL) outer wall calcification, FL thrombus, dilated FL, and tear edges curling into the FL. The model predicted the chronicity of a dissection with an area under the curve of 0.98 (CI 0.98-1.00). AADs and CADs demonstrated significantly different CT imaging features.

Introducing First-Year Medical Students to Radiology: Implementation and Impact.

RATIONALE AND OBJECTIVES: The aims of our study were (1) to describe a new educational intervention for first-year medical students that gave a substantial, early exposure to radiology and (2) to examine how this early exposure was received by the students. MATERIALS AND METHODS: Our new curriculum incorporated a new 2-week course very early in the M1 year entitled Foundations of Diagnostics and Therapeutics. Among other topics, the course included a substantial introduction to radiology primarily through small-group seminars and online materials, administered using a flipped-classroom approach. The students were given pre- and postcourse surveys that assessed the degree to which they felt prepared to learn about radiology, as well as their interest in radiology. Results were analyzed using the Wilcoxon signed-rank test. RESULTS: Survey responses were obtained from 170 students before the course and 65 students afterward. Upon completing the course, students showed significantly increased academic interest in radiology (P = .008) and a heightened perception of the effect of radiology on patient care (P = .04), without a significant change in interest in pursuing radiology as a career. Students showed an overwhelmingly positive response to the course, although some noted that previous anatomy training would have been helpful. Eighty percent agreed or strongly agreed that the flipped-classroom structure was an effective educational model. CONCLUSIONS: Our study demonstrated that students were very excited to gain exposure to radiology early in their medical school curriculum, and such exposure led to an improved perception of the field.

Thoracic radiation-induced pleural effusion and risk factors in patients with lung cancer.

The risk factors and potential practice implications of radiation-induced pleural effusion (RIPE) are undefined. This study examined lung cancer patients treated with thoracic radiation therapy (TRT) having follow-up computed tomography (CT) or 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT. Increased volumes of pleural effusion after TRT without evidence of tumor progression was considered RIPE. Parameters of lung dose-volume histogram including percent volumes irradiated with 5-55 Gy (V5-V55) and mean lung dose (MLD) were analyzed by receiver operating characteristic analysis. Clinical and treatment-related risk factors were detected by univariate and multivariate analyses. 175 out of 806 patients receiving TRT with post-treatment imaging were included. 51 patients (24.9%) developed RIPE; 40 had symptomatic RIPE including chest pain (47.1%), cough (23.5%) and dyspnea (35.3%). Female (OR = 0.380, 95% CI: 0.156-0.926, p = 0.033) and Caucasian race (OR = 3.519, 95% CI: 1.327-9.336, p = 0.011) were significantly associated with lower risk of RIPE. Stage and concurrent chemotherapy had borderline significance (OR = 1.665, p = 0.069 and OR = 2.580, p = 0.080, respectively) for RIPE. Patients with RIPE had significantly higher whole lung V5-V40, V50 and MLD. V5 remained as a significant predictive factor for RIPE and symptomatic RIPE (p = 0.007 and 0.022) after adjusting for race, gender and histology. To include, the incidence of RIPE is notable. Whole lung V5 appeared to be the most significant independent risk factor for symptomatic RIPE.

Pelvic artery aneurysm screening provides value in patients with thoracic aortic aneurysms.

Approximately » of patients with thoracic aortic aneurysms (TAAs) have concomitant abdominal aortic aneurysms (AAAs), thereby justifying the addition of an abdominal CT scan to a chest CT scan in patients with a newly diagnosed or suspected TAA. However, the prevalence of pelvic artery aneurysms (PAAs) in these patients is unknown. The purpose of this study was to determine the prevalence of PAAs in patients with TAAs and to assess what patient specific factors were associated with PAAs, thereby providing insight into the usefulness of pelvic imaging in TAA patients. Consecutive non-operated patients seen in Cardiac Surgery clinic between 2008 and 2013 with a TAA and a CT scan of the chest/abdomen/pelvis were included. Scans of 371 patients were evaluated for PAAs using threshold diameters of 20 and 15 mm for common iliac artery aneurysms (CIAs) and internal iliac artery aneurysms (IIAs), respectively, on 3D analysis. The prevalence of PAAs was determined and multiple logistic regression was used to identify associated risk factors. 41 of 371 (11.1%) patients with a TAA had at least one PAA. Factors showing positive associations with PAAs included increased age (p = 0.0004), male gender (p = 0.0007), descending TAA location (p = 0.0024) and presence of an AAA (p < 0.0001). The results of our study suggest that the addition of pelvic imaging for PAA screening in patients undergoing an initial CT scan of the chest and abdomen for a TAA is valuable, particularly in patients with the following demographics: age ≥65, male gender, descending TAA location, and/or known AAA.

Proximal thoracic aortic diameters: transesophageal-echocardiography- versus computed-tomography-derived measurements.

PURPOSE: The purpose of the study was to compare proximal aortic measurements from electrocardiogram-gated computed tomography (CT) to transesophageal echocardiography (TEE) and to evaluate differences in cusp-cusp and cusp-commissure CT measurements of sinus of Valsalva (SOV). METHODS: This retrospective study (n=25) compared aortic diameters from CT using manual double-oblique multiplanar reformats (MPRs) and semiautomatic centerline method to TEE. RESULTS: CT MPR and centerline measurements were higher than TEE for sinotubular junction and ascending aorta. At SOV, cusp-cusp diameters (MPR and centerline methods) and cusp-commissure measurement (centerline method) were larger than TEE. CONCLUSIONS: Aortic measurements were larger on CT than TEE. Precise difference depended on location and measurement technique.

Evaluation for abdominal aortic aneurysms is justified in patients with thoracic aortic aneurysms.

Aortic aneurysms are a significant cause of mortality, and the presence of multiple aneurysms may affect treatment plans. The purpose of this study was to determine the frequency of abdominal aortic aneurysms (AAAs) in patients with thoracic aortic aneurysms (TAAs) and to establish whether patient specific factors, such as gender and comorbidities, influenced the frequency of AAAs, thereby indicating if and when abdominal aortic evaluation is justified. Electronic medical records were reviewed from 1000 patients with a computed tomography (CT) angiogram of the chest and abdomen and a clinical diagnosis of TAA from Cardiac Surgery clinic between 2008 and 2013. 538 patients with history of aortic intervention, dissection, rupture or trauma were excluded. The frequency of AAAs among the 462 remaining patients was established, and statistical analysis was used to elucidate differences in frequency based on age, gender, comorbidities, and TAA location. Overall, 104 of 462 (22.5 %) patients with a TAA also had an AAA. There were significant differences in the frequency of AAA based on TAA location, age, and comorbidities. The following comorbidities showed positive associations with AAA using logistic regression analysis: age ≥65 (P < 0.0001; OR 30.1; CI 7.14-126.61), smoking history (P < 0.0001; OR 4.1; 2.35-7.30), and hypertension (P = 0.024; OR 2.1; CI 1.11-4.16). Aneurysms in the proximal/mid descending (P < 0.0001; OR 4.96; CI 2.32-10.61) and diaphragm level (P < 0.0001; OR 38.4; CI 14.71-100.15) of the aorta also showed a positive association with AAAs when adjusted for age and gender. AAA screening in patients with TAA is a reasonable, evidence-based option regardless of the TAA location, with the strongest support in patients >age 55, with systemic hypertension, a smoking history and/or a TAA in the descending thoracic aorta.

Pulmonary artery invasion, high-dose radiation, and overall survival in patients with non-small cell lung cancer.

PURPOSE: To investigate whether high-dose radiation to the pulmonary artery (PA) affects overall survival (OS) in patients with non-small cell lung cancer (NSCLC). METHODS AND MATERIALS: Patients with medically inoperable/unresectable NSCLC treated with definitive radiation therapy in prospective studies were eligible for this study. Pulmonary artery involvement was defined on the basis of pretreatment chest CT and positron emission tomography/CT fusion. Pulmonary artery was contoured according to the Radiation Therapy Oncology Group protocol 1106 atlas, and dose-volume histograms were generated. RESULTS: A total of 100 patients with a minimum follow-up of 1 year for surviving patients were enrolled: 82.0% underwent concurrent chemoradiation therapy. Radiation dose ranged from 60 to 85.5 Gy in 30-37 fractions. Patients with PA invasion of grade ≤2, 3, 4, and 5 had 1-year OS and median survival of 67% and 25.4 months (95% confidence interval [CI] 15.7-35.1), 62% and 22.2 months (95% CI 5.8-38.6), 90% and 35.8 months (95% CI 28.4-43.2), and 50% and 7.0 months, respectively (P=.601). Two of the 4 patients with grade 5 PA invasion died suddenly from massive hemorrhage at 3 and 4.5 months after completion of radiation therapy. Maximum and mean doses to PA were not significantly associated with OS. The V45, V50, V55, and V60 of PA were correlated significantly with a worse OS (P<.05). Patients with V45 >70% or V60 >37% had significantly worse OS (13.3 vs 37.9 months, P<.001, and 13.8 vs 37.9 months, P=.04, respectively). CONCLUSIONS: Grade 5 PA invasion and PA volume receiving more than 45-60 Gy may be associated with inferior OS in patients with advanced NSCLC treated with concurrent chemoradiation.

Detection of fibroproliferation by chest high-resolution CT scan in resolving ARDS.

BACKGROUND: In ARDS, the extent of fibroproliferative activity on chest high-resolution CT (HRCT) scan has been reported to correlate with poorer short-term outcomes and pulmonary-associated quality of life. However, clinical factors associated with HRCT scan fibroproliferation are incompletely characterized. We questioned if lung compliance assessed at the bedside would be associated with fibroproliferation on HRCT scans obtained during the resolution phase of ARDS. METHODS: We used data from a published randomized, controlled clinical trial in ARDS. All patients were cared for using a low tidal volume strategy. Demographic data and ventilator parameters were examined in association with radiologic scores from chest HRCT scans obtained 14 days after diagnosis. RESULTS: Data from 82 patients with ARDS were analyzed. Average static respiratory compliance over the first 14 days after diagnosis was inversely associated with chest HRCT scan reticulation (ρ = -0.46); this relationship persisted in multivariable analysis including APACHE (Acute Physiology and Chronic Health Evaluation) II scores, initial Pao2/Fio2, pneumonia diagnosis, and ventilator days. Average static respiratory compliance was also lower among patients with bronchiectasis at day 14 (P = .007). Initial static respiratory compliance obtained within the first day after ARDS diagnosis was correlated inversely with the presence of HRCT scan reticulation (ρ = -0.38) and was lower among patients who demonstrated bronchiectasis on the day 14 HRCT scan (P = .008). CONCLUSIONS: In patients with ARDS, diminished lung compliance measured bedside was associated with radiologic fibroproliferation 14 days post diagnosis. Establishing factors that predispose to development of excessive fibroproliferation with subsequent confirmation by chest HRCT scan represents a promising strategy to identify patients with ARDS at risk for poorer clinical outcomes.

Imaging in thoracic oncology: case studies from Multidisciplinary Thoracic Tumor Board: (part 2 of 2 part series).

Multidisciplinary tumor board conferences foster collaboration among health care providers from a variety of specialties and help to facilitate optimal patient care. Generally, the clinical questions revolve around the best options for establishing a diagnosis, staging the disease and directing treatment. This article describes and illustrates the clinical scenarios of three patients who were presented at our thoracic Tumor Board, focusing on management issues and the role of imaging. These patients had invasive thymoma; concurrent small cell lung cancer and non-small cell lung cancer; and esophageal cancer with celiac lymph node metastases, respectively.

Imaging in thoracic oncology: case studies from Multidisciplinary Thoracic Tumor Board (part 1 of 2 part series).

Multidisciplinary tumor board conferences foster collaboration among health care providers from a variety of specialties and help to facilitate optimal patient care. Typical cases from thoracic tumor board conferences include patients with known or suspected bronchogenic and esophageal carcinomas, as well as less common diseases such as thymomas and mesotheliomas. In most instances, the clinical questions revolve around the best options for establishing a diagnosis, staging the disease and directing treatment. This article describes and illustrates the clinical scenarios of three patients who were presented at our tumor board, focusing on management issues and the role of imaging. These patients had non-small cell lung cancer and mediastinal lymph node metastases; a small, growing ground glass nodule; and oligometastatic non-small cell lung cancer, respectively.

Incidental, subsolid pulmonary nodules at CT: etiology and management.

Pulmonary nodules, both solid and subsolid, are common incidental findings on computed tomography (CT) studies. Subsolid nodules (SSNs) may be further classified as either pure ground-glass nodules or part-solid nodules. The differential diagnosis for an SSN is broad, including infection, organizing pneumonia, inflammation, hemorrhage, focal fibrosis, and neoplasm. Adenocarcinomas of the lung are currently the most common type of lung cancer, representing 30-35% of all primary lung tumors, and the subtype of bronchioloalveolar cell carcinoma (BAC) commonly presents as an SSN. In 2011, a new classification system for lung adenocarcinomas was proposed by the International Association for the Study of Lung Cancer, the American Thoracic Society, and the European Respiratory Society. An important feature of the new system is the relinquishment of the term BAC in favor of more specific histologic subtypes. It has been reported that these subtypes are associated with characteristic CT findings. This article reviews the new classification system of lung adenocarcinomas, discusses and illustrates the associated CT findings, and outlines the current recommendations for further diagnosis, treatment, and follow-up of SSNs based on computed tomography findings.

Chest CT features are associated with poorer quality of life in acute lung injury survivors.

OBJECTIVES: Despite decreasing mortality rates in acute lung injury, studies of long-term physical function in acute lung injury survivors have consistently reported poorer quality of life persisting years into recovery for reasons that are not completely understood. We sought to determine if pulmonary dysfunction is independently associated with functional impairment among acute lung injury survivors and to determine if high-resolution computed tomography could be used to predict its development. DESIGN: Secondary analysis of data from a randomized controlled trial in acute lung injury. SETTING: ICUs at three academic medical centers. PATIENTS: Patients diagnosed with acute lung injury who had high-resolution computed tomography scans performed at 14 and/or 180 days after diagnosis. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: An objective radiologic scoring system was used to quantify patterns present on chest high-resolution computed tomography obtained at 14 and 180 days in patients with acute lung injury. These scores were correlated in univariable and multivariable analyses with pulmonary function testing and quality of life survey data obtained at 180 days. Eighty-nine patients had evaluable data at day 14, and 47 at 180 days. At 180 days, increased radiologic scores for reticulation were associated with a decreased total lung capacity, forced vital capacity, and diffusing capacity for carbon monoxide (p values all < 0.002). Decrements in quality of life attributable to pulmonary dysfunction were most strongly associated with higher radiologic scores. Additionally, radiologic scores at 14 days independently predicted poorer quality of life at 180 days, accounting for age, severity of illness, pneumonia as the acute lung injury risk factor, and length of time on mechanical ventilation. CONCLUSIONS: Among survivors of acute lung injury, increasing chest high-resolution computed tomography involvement correlated with restrictive physiology and poorer health-related quality of life, implicating pulmonary dysfunction as a potential contributor to activity limitation in these patients.

Proximal thoracic aortic diameter measurements at CT: repeatability and reproducibility according to measurement method.

AIM: To determine the variability in CT measurements of proximal thoracic aortic diameters obtained using double-oblique short axis and semiautomatic centerline analysis techniques. Institutional review board approval, with waiver of informed consent, was obtained for this HIPAA-compliant, retrospective study. Cardiac gated thoracic aortic CT scans were evaluated in 25 patients. Maximum aortic diameter measurements at the annulus, sinuses, sinotubular junction and ascending aorta were generated using double-oblique short axis and semiautomatic centerline analysis techniques. Intraobserver and interobserver variability and variability between techniques were assessed using the Wilcoxon signed rank test, Spearman's correlation coefficients and Bland-Altman plots. Mean intraobserver diameter differences using double oblique views ranged from -0.3 to 0.6 mm. The 95 % confidence interval for difference in diameters was ±2.4 to ±5.1 mm for radiologist #1 and ±2.6 to ±5.2 mm for radiologist #2, depending on location. Mean intraobserver diameter differences using centerline analysis ranged from 0.2 to 2.3 mm, and the 95 % confidence interval for difference in diameters was ±2.0 to ±4.6 mm, depending on location. Significant interobserver differences were seen for both double oblique views and centerline analysis. Measurements obtained using the two methods were strongly correlated (r = 0.81-0.99), although they were consistently larger using centerline analysis (95 % confidence interval, ±1.8 to ±3.2 mm). Although measurement variability of the proximal thoracic aorta was generally low using double oblique and centerline analysis techniques, differences of up to approximately 5 mm in diameter occurred within the 95 % confidence interval. Neither technique was clearly more reliable than the other.

Natural growth and disease progression of non-small cell lung cancer evaluated with 18F-fluorodeoxyglucose PET/CT.

PURPOSE: The aims of this study were to: (1) estimate the volumetric and metabolic growth rate of non-small cell lung cancer (NSCLC), (2) evaluate disease progression prior to treatment, and (3) explore the effects of tumor growth rate and time to treatment (TTT) on survival outcome. METHODS: Patients with inoperable stages I-III NSCLC with serial pre-treatment PET/CT scans were eligible for this study. PET-derived metabolic tumor volumes (PET-MTV) and CT-derived gross tumor volumes (CT-GTV) were contoured using PET/CT information. Normalized standardized uptake values (NSUV) in tumors including the NSUVmean and NSUVmax were measured. Tumor growth rates expressed as doubling time (DT) were estimated using an exponential model. Pre-treatment disease progression defined as the development of any new site of disease on PET/CT and change in TNM stage (AJCC 7th ed.) were recorded. Growth rate and tumor progression were analyzed with respect to overall (OS) and progression free survival (PFS). RESULTS: Thirty-four patients with a median inter-scan interval (ISI) of 43 days and TTT of 48 days were analyzed. Tumor volumes showed remarkable inter-scan growth while NSUV did not increase significantly. The DT for PET-MTV, CT-GTV, NSUVmean and NSUVmax were 124, 139, 597, and 333 days, respectively. Pre-treatment disease progression occurred in 20.6% patients with longer ISI being a significant risk factor (OR=1.027, p=0.02). The optimal threshold ISI to predict progression was 58 days (4.8% vs. 46.2%, p=0.007). Neither tumor growth rates nor TTT were significantly correlated to OS or PFS. CONCLUSIONS: NSCLC displays rapid tumor volume growth whereas NSUVmean and NSUVmax are relatively stable over the same time period. Longer delays before initiation of treatment are associated with higher risk of pre-treatment disease progression.

Chest CT incidentalomas: thyroid lesions, enlarged mediastinal lymph nodes, and lung nodules.

A computed tomography (CT) incidentaloma is an incidentally detected and previously unsuspected finding or abnormality that is not related to the indication for obtaining the CT examination. The aim of this article is to review the frequency of incidentalomas on chest CT scans, discuss the potential clinical significance of the findings, and suggest guidelines for reporting, further evaluation, and follow-up, with particular focus on thyroid lesions, enlarged mediastinal lymph nodes and lung nodules.

"Sweet spot" for endoleak detection: optimizing contrast to noise using low keV reconstructions from fast-switch kVp dual-energy CT.

OBJECTIVE: To assess endoleak detection and conspicuity using low-kiloelectron volt (keV) monochromatic reconstructions of single-source (fast-switch kilovolt [peak]) dual-energy data sets. METHODS: With approval of the institutional review board, multiphasic dual-energy computed tomographic (CT) scans for aortic endograft surveillance were retrospectively reviewed for 39 patients. Two abdominal radiologists each performed 2 separate reading sessions, at 55-keV and standard 75-keV reconstruction, respectively. The readers tabulated endoleak presence, conspicuity on 1-to-5 scale, and type overall and in arterial and venous phases. Originally, dictated reports in medical records were used as criterion standard. RESULTS: Original dictations identified 19 endoleaks (9 abdominal and 10 thoracic), 13 of which were type II. The blinded readers (R1 and R2) exhibited good to very good intraobserver and interobserver agreement. Endoleak detection was higher at 55 keV than at 75 keV (sensitivity, 100% (95% confidence interval [CI], 82.4%-100.0%) and 84.2% (95% CI, 60.4-96.6%) at 55 keV vs 79% (95% CI, 54.4-94.0%) and 68.4% (95% CI, 43.5%-87.4%) at 75 keV in venous phase). Further, endoleak conspicuity ratings (where original dictation showed positive leak) were higher at 55 keV than at 75 keV, which was a significant difference for R2 in the overall ratings (P = 0.03) and for both readers in the venous phase ratings (R1, P = 0.01; R2, P = 0.004). There was no difference in endoleak type characterization between the kiloelectron volt levels. CONCLUSION: Sensitivity for endoleak detection and overall endoleak conspicuity ratings were both higher at 55 keV than 75 keV, favoring the inclusion of a lower-energy monochromatic reconstruction for endoleak surveillance protocols with dual-energy computed tomography.

Embryology and imaging review of aortic arch anomalies.

Congenital malformations of the thoracic aorta can be discovered on chest radiographs when associated with symptoms or found incidentally. We review the imaging anatomy and associations of many of the aortic arch malformations that can be encountered in adults and highlight key points with regard to their treatment and prognoses. An understanding of the normal and abnormal embryologic development of the aortic arch, with knowledge of their imaging features, may be important for improving diagnostic accuracy and patient care.