Faculty Bibliography

Quantitative radiomic and iodine imaging features have been explored for diagnosis and characterization of tumors. In this work, we invistigate combined whole-lesion radiomic and iodine analysis for the differentiation of pulmonary tumors on contrast-enhanced dual-energy CT (DECT) chest images. 100 biopsy-proven solid lung lesions on contrast-enhanced DECT chest exams within 3 months of histopathologic sampling were identified. Lesions were volumetrically segmented using open-source software. Lesion segmentations and iodine density volumes were loaded into a radiomics prototype for quantitative analysis. Univariate analysis was performed to determine differences in volumetric iodine concentration (mean, median, maximum, minimum, 10th percentile, 90th percentile) and first and higher order radiomic features (n = 1212) between pulmonary tumors. Analyses were performed using a 2-sample t test, and filtered for false discoveries using Benjamini-Hochberg method. 100 individuals (mean age 65 ± 13 years; 59 women) with 64 primary and 36 metastatic lung lesions were included. Only one iodine concentration parameter, absolute minimum iodine, significantly differed between primary and metastatic pulmonary tumors (FDR-adjusted p = 0.015, AUC 0.69). 310 (FDR-adjusted p = 0.0008 to p = 0.0491) radiomic features differed between primary and metastatic lung tumors. Of these, 21 features achieved AUC ≥ 0.75. In subset analyses of lesions imaged by non-CTPA protocol (n = 72), 191 features significantly differed between primary and metastatic tumors, 19 of which achieved AUC ≥ 0.75. In subset analysis of tumors without history of prior treatment (n = 59), 40 features significantly differed between primary and metastatic tumors, 11 of which achieved AUC ≥ 0.75. Volumetric radiomic analysis provides differentiating capability beyond iodine quantification. While a high number of radiomic features differentiated primary versus metastatic pulmonary tumors, fewer features demonstrated good individual discriminatory utility.

Purpose: To determine yield of subsolid lesion core biopsy, and factors influencing yield
Material(s) and Method(s): A retrospective review of percutaneous lung biopsies from 1/1/2013 to 2/31/2019 was performed, resulting 2350 cases. Imaging was reviewed to classify lesions by attenuation; of which 363 lesions were subsolid. Subsolid lesions were defined as those with any ground-glass component. Each lesion was characterized by lobar location, long and short axis length, percent solid component, and presence of cystic components. Procedure reports were reviewed to determine needle gauge, number of passes, and patient position. Histopathology was reviewed to determine whether sampling was diagnostic, and if so, whether results benign, neoplastic, or equivocal. All lesions with benign/equivocal results underwent subsequent chart review. Of diagnostic samples, accuracy for malignancy was calculated among those for which definitive diagnosis was established. Linear regression analysis was performed to evaluate influence of lesion features on biopsy yield,.05 significance level.
Result(s): The cohort included 215 women (59%), with average age 72 years (range 19-94). 99% of core biopsies were obtained with 20-gauge needle. Core biopsies of subsolid lesions were diagnostic in 318/363 (88%) cases, of which 266/318 (84%) resulted neoplastic pathology, 29 (9%) benign, and 23 equivocal (7%). Of the benign lesions, 20/29 were confirmed (resolution, stability >24 months, and/or resection), 1 lesion was neoplastic, and 8 lacked sufficient follow-up. Of the equivocal core biopsies, 8/23 proved neoplastic, 1 benign, and 14 indeterminate. Of 45 non-diagnostic samples, 15 subsequently proved neoplastic (4 by concurrent FNA and 11 by resection), 1 benign (resolution), and the remainder indeterminate. Of 296 diagnostic samples for which there was sufficient follow-up/intervention to confirm diagnosis, sensitivity of subsolid lesion core biopsy for diagnosis of malignancy was 97%, with specificity of 100%. For lesions in which solid component was graded less than 50% of total lesion size, diagnostic yield decreased to 80% (144/179). ANOVA demonstrated solid component size to be an independent predictor of diagnostic core biopsy. Lesion location, size, percent solid component, lucencies, patient position, and number of passes were not significant factors influencing diagnostic yield.
Conclusion(s): Diagnostic yield of 20-guage core biopsy for subsolid lesions is influenced by solid component size. Sensitivity of subsolid lesion core biopsy for diagnosis of malignancy is high.
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Purpose: To evaluate the cryoablation zones generated in human subjects during the treatment of pulmonary tumors using 14-gauge cryoablation probes; current understanding of in vivo pulmonary cryoablation zone volumes stems predominantly from study of 17-gauge probes
Material(s) and Method(s): A single-center database of all adult patients who underwent CT-guided cryoablation of pulmonary tumors between August 2017 and June 2020 was compiled. All patients were treated using one or more 14-gauge cryoablation probes. Intraprocedural and 1- to 2-month post-procedural chest CTs were evaluated to characterize pulmonary lesions, procedural ice balls, and follow-up ablation zones. Comparison of single-probe ablation zone volumes to manufacturer reference values, and to previously published data on 17-gauge probes was performed using the Wilcoxon rank-sum test. Comparison of ablation zone volume to the number of probes used, distance of the pulmonary lesion to the pleura, and distance of the pulmonary lesion to the nearest >=3 mm vessel, were performed using Kruskal-Wallis and Pearson correlation tests.
Result(s): Pulmonary cryoablation was performed on 47 pulmonary lesions (64% primary adenocarcinoma) across 45 unique procedures on 42 patients (Female: 50%; Mean age: 75.2 +/- 11.5 years). Mean intraprocedural ice ball volume when 1, 2, or 3 probes were used was 5.4 +/- 3.8, 8.0 +/- 4.8, and 22.9 +/- 10.8 cm³, respectively. Mean cryoablation zone volume at 1-2 months when 1, 2, or 3 probes were used was 5.0 +/- 2.3, 37.5 +/- 20.5, and 28.4 cm³, respectively (n = 1 for 3 probes). Mean single-probe ablation zone volume (5.0 +/- 2.3 cm³) was significantly larger than that previously reported for 17-gauge probes (3.0 +/- 0.3 cm³) (P = 0.014)¹, but significantly smaller than manufacturer-reported in vitro 0degreeC, -20degreeC, and -40degreeC isotherms (all P < 0.0001). The number of probes was significantly associated with ablation zone volume (P = 0.0033). Mean cryoablation zone volume was not significantly associated with lesion distance to pleura (P=0.40) or lesion distance to the nearest >=3 mm vessel (P = 0.60).
Conclusion(s): Single-probe pulmonary cryoablation with 14-gauge probes generates significantly larger ablation zone volumes than with 17-gauge probes. In vivo pulmonary cryoablation generates significantly smaller ablation zone volumes than manufacturer-reported in vitro isotherms. Use of multiple probes significantly increased ablation zone volume compared with use of a single probe.
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OBJECTIVE:To evaluate the inter-observer consistency for subsolid pulmonary nodule radiomic features. MATERIALS AND METHODS/METHODS:Subsolid nodules were selected by reviewing radiology reports of CT examinations performed December 1, 2015 to April 1, 2016. Patients with CTs at two time points were included in this study. There were 55 patients with subsolid nodules, of whom 14 had two nodules. Of 69 subsolid nodules, 66 were persistent at the second time point, yielding 135 lesions for segmentation. Two thoracic radiologists and an imaging fellow segmented the lesions using a semi-automated volumetry algorithm (Syngo.via Vb20, Siemens). Coefficient of variation (CV) was used to assess consistency of 91 quantitative measures extracted from the subsolid nodule segmentations, including first and higher order texture features. The accuracy of segmentation was visually graded by an experienced thoracic radiologist. Influencing factors on radiomic feature consistency and segmentation accuracy were assessed using generalized estimating equation analyses and the Exact Mann-Whitney test. RESULTS:Mean patient age was 71 (38-93 years), with 39 women and 16 men. Mean nodule volume was 1.39mL, range .03-48.2mL, for 135 nodules. Several radiomic features showed high inter-reader consistency (CV<5%), including entropy, uniformity, sphericity, and spherical disproportion. Descriptors such as surface area and energy had low consistency across inter-reader segmentations (CV>10%). Nodule percent solid component and attenuation influenced inter-reader variability of some radiomic features. The presence of contrast did not significantly affect the consistency of subsolid nodule radiomic features. Near perfect segmentation, within 5% of actual nodule size, was achieved in 68% of segmentations, and very good segmentation, within 25% of actual nodule size, in 94%. Morphologic features including nodule margin and shape (each p <0.01), and presence of air bronchograms (p = 0.004), bubble lucencies (p = 0.02) and broad pleural contact (p < 0.01) significantly affected the probability of near perfect segmentation. Stroke angle (p = 0.001) and length (p < 0.001) also significantly influenced probability of near perfect segmentation. CONCLUSIONS:The inter-observer consistency of radiomic features for subsolid pulmonary nodules varies, with high consistency for several features, including sphericity, spherical disproportion, and first and higher order entropy, and normalized non-uniformity. Nodule morphology influences the consistency of subsolid nodule radiomic features, and the accuracy of subsolid nodule segmentation.

ABSTRACT/UNASSIGNED:Percutaneous computed tomography-guided transthoracic lung biopsy is an effective and minimally invasive procedure to achieve tissue diagnosis. Radiologists are key in appropriate referral for further workup, with percutaneous computed tomography-guided transthoracic lung biopsy performed by both thoracic and general interventionalists. Percutaneous computed tomography-guided transthoracic lung biopsy is increasingly performed for both diagnostic and research purposes, including molecular analysis. Multiple patient, lesion, and technique-related variables influence diagnostic accuracy and complication rates. A comprehensive understanding of these factors aids in procedure planning and may serve to maximize diagnostic yield while minimizing complications, even in the most challenging scenarios.

Pulmonary nodules are the most common incidental finding in the chest, particularly on computed tomographs that include a portion or all of the chest, and may be encountered more frequently with increasing utilization of cross-sectional imaging. Established guidelines address the reporting and management of incidental pulmonary nodules, both solid and subsolid, synthesizing nodule and patient features to distinguish benign nodules from those of potential clinical consequence. Standard nodule assessment is essential for the accurate reporting of nodule size, attenuation, and morphology, all features with varying risk implications and thus management recommendations.

OBJECTIVE:To evaluate the influence of coronary artery dominance on observed coronary artery calcification burden in outpatients presenting for coronary computed tomography angiography (CCTA). METHODS:A 12-month retrospective review was performed of all CCTAs at a single institution. Coronary arterial dominance, Agatston score and presence or absence of cardiovascular risk factors including hypertension (HTN), hyperlipidemia (HLD), diabetes and smoking were recorded. Dominance groups were compared in terms of calcium score adjusted for covariates using analysis of covariance based on ranks. Only covariates observed to be significant independent predictors of the relevant outcome were included in each analysis. All statistical tests were conducted at the two-sided 5% significance level. RESULTS:1223 individuals, 618 women and 605 men were included, mean age 60 years (24-93 years). Right coronary dominance was observed in 91.7% (n = 1109), left dominance in 8% (n = 98), and codominance in 1.3% (n = 16). The distribution of patients among Agatston score severity categories significantly differed between codominant and left (p = 0.008), and codominant and right (p = 0.022) groups, with higher prevalence of either zero or severe CAC in the codominant patients. There was no significant difference in Agatston score between dominance groups. In the subset of individuals with coronary artery calcification, Agatston score was significantly higher in codominant versus left dominant patients (mean Agatston score 595 ± 520 vs. mean 289 ± 607, respectively; p = 0.049), with a trend towards higher scores in comparison to the right-dominant group (p = 0.093). Significance was not maintained upon adjustment for covariates. CONCLUSIONS:While the distribution of Agatston score severity categories differed in codominant versus right- or left-dominant patients, there was no significant difference in Agatston score based on coronary dominance pattern in our cohort. Reporting and inclusion of codominant subsets in larger investigations may elucidate whether codominant anatomy is associated with differing risk.

Lung transplant is increasingly performed for the treatment of end-stage lung disease. As the number of lung transplants and transplant centers continues to rise, radiologists will more frequently participate in the care of patients undergoing lung transplant, both before and after transplant. Potential donors and recipients undergo chest radiography and CT as part of their pretransplant assessment to evaluate for contraindications to transplant and to aid in surgical planning. After transplant, recipients undergo imaging during the postoperative hospitalization and also in the long-term outpatient setting. Radiologists encounter a wide variety of conditions leading to end-stage lung disease and a myriad of posttransplant complications, some of which are unique to lung transplantation. Familiarity with these pathologic conditions, including their imaging findings and their temporal relationship to the transplant, is crucial to accurate radiologic interpretation. Knowledge of the surgical techniques and expected postoperative appearance prevents confusing normal posttransplant imaging findings with complications. A basic understanding of the indications, contraindications, and surgical considerations of lung transplant aids in imaging interpretation and protocoling and also facilitates communication between radiologists and transplant physicians. Despite medical and surgical advances over the past several decades, lung transplant recipients currently have an average posttransplant life expectancy of only 6.7 years. As members of the transplant team, radiologists can help maximize patient survival and hopefully increase posttransplant life expectancy and quality of life in the coming decades. ^©RSNA, 2021 An invited commentary by Bierhals is available online. Online supplemental material is available for this article.

OBJECTIVES/OBJECTIVE:To describe the histologic features that are helpful in the diagnosis of the rare bronchiolar adenomas/ciliated muconodular papillary tumors (BAs/CMPTs) during intraoperative consultation. METHODS:Multi-institutional retrospective review of frozen sections of 18 BAs/CMPTs. RESULTS:In 14 of 18 cases, BA/CMPT was the primary reason for sublobar lung resection, and in 4 cases, BA/CMPT was an incidental finding intraoperatively for resections performed for carcinoma in other lobes. There were 11 proximal-type/classic BAs/CMPTs and 7 distal-type/nonclassic BAs/CMPTs. Only 3 (16.7%) of 18 were correctly diagnosed at the time of frozen section, all of which were proximal type/classic. The remainder were diagnosed as adenocarcinoma (n = 7); invasive mucinous adenocarcinoma (n = 1); non-small cell lung carcinoma (n = 1); cystic mucinous neoplasm, favor adenocarcinoma (either mucinous or colloid type) (n = 1); favor adenocarcinoma, cannot exclude CMPT (n = 1); atypical proliferation (n = 2); mucinous epithelial proliferation (n = 1); and mucous gland adenoma (n = 1). CONCLUSIONS:BA/CMPT can potentially be misdiagnosed as carcinoma during intraoperative consultation. On retrospective review of the frozen sections, the presence of the following may help to avoid misdiagnosis: a mixture of bland ciliated columnar cells, mucinous cells, and, most important, a basal cell layer, as well as a lack of necrosis, significant atypia, and mitoses.

During the coronavirus disease 2019 (COVID-19) pandemic, rapid and accurate triage of patients at the emergency department is critical to inform decision-making. We propose a data-driven approach for automatic prediction of deterioration risk using a deep neural network that learns from chest X-ray images and a gradient boosting model that learns from routine clinical variables. Our AI prognosis system, trained using data from 3661 patients, achieves an area under the receiver operating characteristic curve (AUC) of 0.786 (95% CI: 0.745-0.830) when predicting deterioration within 96 hours. The deep neural network extracts informative areas of chest X-ray images to assist clinicians in interpreting the predictions and performs comparably to two radiologists in a reader study. In order to verify performance in a real clinical setting, we silently deployed a preliminary version of the deep neural network at New York University Langone Health during the first wave of the pandemic, which produced accurate predictions in real-time. In summary, our findings demonstrate the potential of the proposed system for assisting front-line physicians in the triage of COVID-19 patients.