Faculty Bibliography

Cardiac magnetic resonance (CMR) imaging has gained significant traction as an imaging modality of choice in the evaluation of individuals with, or at risk for, heart failure. Ventricular arrhythmias, often malignant, may be sequelae of heart failure and arise from fibrosis. Late gadolinium enhancement evaluation by CMR has become a preferred modality to assess individuals at risk for malignant ventricular arrhythmias. A spectrum of various pathologies that predispose individuals to malignant ventricular arrhythmias, as well as the usefulness of CMR in their identification and prognostication, are reviewed.

Diffuse lung metastases have been reported in non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations. The purpose of our study was to compare the incidence of diffuse lung metastases in EGFR-mutant NSCLC and EGFR-wild type NSCLC and to assess other imaging features that may be associated with diffuse lung metastases in EGFR-mutant NSCLC. Two radiologists retrospectively reviewed pre-treatment imaging of metastatic NSCLC cases with known EGFR mutation status. We assessed the imaging features of the primary tumor and patterns of metastases. The cohort consisted of 217 patients (117 EGFR-mutant, 100 EGFR wild-type). Diffuse lung metastasis was significantly more common in EGFR-mutant NSCLC compared with wild-type (18% vs. 3%, p < 0.01). Among the EGFR-mutant group, diffuse lung metastases were inversely correlated with the presence of a nodule greater than 6 mm other than the primary lung lesion (OR: 0.13, 95% CI: 0.04-0.41, p < 0.01). EGFR mutations in NSCLC are associated with increased frequency of diffuse lung metastases. The presence of diffuse lung metastases in EGFR-mutant NSCLC is also associated with a decreased presence of other larger discrete lung metastases. EGFR mutations in NSCLC should be suspected in the setting of a dominant primary lung mass associated with diffuse lung metastases.

INTRODUCTION:Several studies have suggested that non-small-cell lung cancer (NSCLC) patients who harbor anaplastic lymphoma kinase (ALK) rearrangement might have different imaging features compared with those without the rearrangement. The goal of this work was to systematically investigate the computed tomography (CT) imaging features of ALK-rearranged NSCLC. MATERIALS AND METHODS:We searched published studies that investigated CT imaging features of ALK-rearranged NSCLC compared with ALK-negative, including epidermal growth factor receptor (EGFR)-mutant and ALK/EGFR-negative, NSCLC. We extracted clinicopathologic characteristics and CT imaging features of patients in the included studies. Features were compared and tested in the form of odds ratios (ORs) or weighted mean differences at a 95% confidence interval. RESULTS:Twelve studies with 2210 patients with NSCLC were included. Compared with ALK-negative NSCLC, ALK-rearranged NSCLC was more likely to be solid (OR, 2.37; P < .001) and less likely to have cavitation (OR, 0.45; P = .002). In advanced stages, patients with ALK-rearranged NSCLC, compared with EGFR-mutant NSCLC, were more likely to have lymphadenopathy (OR, 3.47; P < .001), pericardial metastasis (OR, 2.18; P = .04), pleural metastasis (OR, 2.07; P = .004), and lymphangitic carcinomatosis (OR, 3.41; P = .02), but less likely to have lung metastasis (OR, 0.52; P = .003). Compared with ALK/EGFR-negative NSCLC, ALK-rearranged NSCLC was more likely to have lymphangitic carcinomatosis (OR, 3.88; P = .03), pleural metastasis (OR, 1.89; P = .02), and pleural effusion (OR, 2.94; P = .003). CONCLUSION:ALK-rearranged NSCLC has imaging features that are different compared with EGFR-mutant and ALK/EGFR-negative NSCLC. These imaging features might provide clues as to the presence of ALK rearrangement and help in the selection of patients who might benefit from expedited molecular testing or repeat testing after a negative assay.

OBJECTIVES/OBJECTIVE:The objective of this study was to determine the effect of a lobectomy to the location and orientation of nonresected lung nodule and its corresponding airway. METHODS:We reviewed preoperative and postoperative computed tomography of patients who underwent lobectomies and have a separate nonresected nodule in the ipsilateral lung. Displacement of the nonresected nodule and angulation of its corresponding segmental bronchus were measured. RESULTS:Fifty nodules from 40 patients (30 females, 10 male; mean ± SD age, 67 ± 7 years) were assessed. Nodules are displaced clockwise after right upper, right middle, and left lower lobectomies and counterclockwise after right lower and left upper lobectomies. Displacement of the remaining nodules was greater in the craniocaudal plane, followed by anteroposterior and transverses planes (mean, 3.7, 2.5, and 1.9 cm, respectively). CONCLUSIONS:Remaining ipsilateral nodules and their associated segmental airways are displaced in a predictable fashion after lobectomy. This may help in the assessment of follow-up imaging.

PURPOSE/OBJECTIVE:The objective of this study was to assess the reliability of ancillary imaging findings in distinguishing acute from chronic aortic dissection (AD) and intramural hematoma (IMH) using computed tomography angiography (CTA). MATERIALS AND METHODS/METHODS:Two radiologists specializing in cardiothoracic and vascular imaging reviewed paired CTAs of patients with AD or IMH who underwent CTA in the acute (within 24 h of presentation) and chronic settings. The radiologists were blinded to the temporal order of the CTAs. Minimum and maximum flap thicknesses and presence or absence of pleural effusion, pericardial effusion, mediastinal hematoma or fat standing, and mediastinal lymphadenopathy were recorded. RESULTS:Patients included 25 male individuals and 13 female individuals with a mean age of 59 years (range: 34 to 87 y). The group included 29 AD and 9 IMH cases. The median interval between the paired CTs was 542 days (range: 100 to 2533 d). Respectively, the mean minimum flap thicknesses in the acute and chronic AD were 1.3 and 1.4 mm (P=0.3), and the mean maximum flap thicknesses were 2.7 and 2.9 mm (P=0.29). The incidences of ancillary findings in acute and chronic AD and IMH were as follows: pleural effusion (55% vs. 37%, P=0.143), pericardial effusion (8% vs. 11%, P=1.0), lymphadenopathy (47% vs. 47%, P=1.0), and periaortic fat stranding (87% vs. 76%, P=0.344). CONCLUSIONS:Ancillary CT imaging findings traditionally ascribed to acute AD and IMH are also often found in the chronic setting and are not reliable indicators of acuity. Flap thickness in AD may not be a reliable imaging indicator of acuity of AD.

OBJECTIVES:Mutations in the BRAF gene have emerged as a validated molecular target in the treatment of non-small cell lung cancer (NSCLC). These mutations can be classified into three functional classes based on their mechanisms of oncogenesis. The relationship between these functional classes and their imaging features has not been systematically investigated. The goal of this work is to determine if imaging features of the primary tumor and the pattern of metastasis correlate with the functional class of BRAF mutation. METHODS:We reviewed pre-treatment computed tomography (CT) images of patients with BRAF-mutated NSCLC with known functional class. We assessed and recorded the features of the primary tumor and the patterns of lymphadenopathy and distant metastasis. Wilcoxon rank-sum test and Kruskal-Wallis test were performed to compare continuous characteristics, and Fisher's exact test was used to compare categorical features between groups. RESULTS AND CONCLUSIONS:105 patients with BRAF-mutant NSCLC had pre-treatment imaging available for review (n = 43 class I, n = 40 class II, and n = 22 class III). Approximately half of the primary tumors were considered masses (n = 54/105, 51%) and most were solid (n = 81/105, 77%). There were no statistically significant differences in imaging features of the primary tumor among the three functional classes. Intrathoracic metastases occurred more frequently in class I tumors compared to tumors with class II and III mutations (p = 0.03). The odds of class I mutation were higher among tumors involving the pleural space (OR: 4.39, 95% CI: 1.11-17.4) and lower among tumors disseminating to the abdomen (OR: 0.25, 95% CI: 0.07-0.92). Our findings suggest that class I (V600) mutated NSCLC may be more likely to have intrathoracic metastases, while classes II and III (non-V600) mutated NSCLC may be more likely to have intra-abdominal metastases at the time of presentation.

Research and other scholarly activities are an important and required component of diagnostic radiology training. Several strategies, both at the departmental and the larger organizational levels, have been implemented to encourage radiology trainees to participate in these activities. In this article, we review and discuss our institution's 10-year experience in supporting the development and realization of scholarly projects through a competitive intramural grant for residents.