Publications

PURPOSE: To evaluate the utility of pelvic computed tomography (CT) in emergency department (ED) patients undergoing chest CT angiogram (CTA) for chest pain or suspected pulmonary embolism (PE) followed by abdominopelvic CT in the same session for additional multisystem or generalized complaints.

METHODS: This retrospective study included consecutive adult ED patients from January 2017 to December 2019 who underwent CTA for suspected PE followed by portovenous abdominopelvic CT for multisystem or generalized complaints. Patient demographics, vitals, laboratory values, exam indication, malignancy history, and recent surgery/intervention were recorded. CT reports were reviewed for acute chest, abdomen, and/or pelvic pathology.

RESULTS: There were 400 patients with 243 (61%) women and mean age of 59.8 years. Acute pelvic findings were seen in 11% (45/400). In 53% (24/45) of these, pelvic pathology could be diagnosed based on the abdominal portion of the CT. Five percent (21/400) of patients demonstrated isolated acute pelvic findings with 86% of these (18/21) clinically suspected prior to imaging. Acute pelvic pathology was associated with female gender (p = 0.015) and elevated white blood cell count (WBC) (p = 0.03). Specific pelvic CT indications and female gender were significantly associated with (p = 0.02 each) and independent predictors of isolated acute pelvic pathology.

CONCLUSION: In ED patients undergoing chest CTA for chest pain or suspected PE combined with abdominopelvic CT, the presence of acute pelvic-related pathology not visualized on abdominal CT is low. For this ED patient cohort, pelvic CT may not be necessary in men with normal WBC and a low pre-imaging clinical suspicion for acute pelvic pathology.

Radiofrequency ablation (RFA) of intrahepatic tumors induces distant tumor growth through activation of interleukin 6/signal transducer and activator of transcription 3 (STAT3)/hepatocyte growth factor (HGF)/tyrosine-protein kinase Met (c-MET) pathway. Yet, the predominant cellular source still needs to be identified as specific roles of the many types of periablational infiltrating immune cells requires further clarification. Here we report the key role of activated myofibroblasts in RFA-induced tumorigenesis and successful pharmacologic blockade. Murine models simulating RF tumorigenic effects on a macrometastatic tumor and intrahepatic micrometastatic deposits after liver ablation and a macrometastatic tumor after kidney ablation were used. Immune assays of ablated normal parenchyma demonstrated significantly increased numbers of activated myofibroblasts in the periablational rim, as well as increased HGF levels, recruitment other cellular infiltrates; macrophages, dendritic cells and natural killer cells, HGF dependent growth factors; fibroblast growth factor-19 (FGF-19) and receptor of Vascular Endothelial Growth Factor-1 (VEGFR-1), and proliferative indices; Ki-67 and CD34 for microvascular density. Furthermore, macrometastatic models demonstrated accelerated distant tumor growth at 7d post-RFA while micrometastatic models demonstrated increased intrahepatic deposit size and number at 14 and 21 days post-RFA. Multi-day atorvastatin, a selective fibroblast inhibitor, inhibited RFA-induced HGF and downstream growth factors, cellular markers and proliferative indices. Specifically, atorvastatin treatment reduced cellular and proliferative indices to baseline levels in the micrometastatic models, however only partially in macrometastatic models. Furthermore, adjuvant atorvastatin completely inhibited accelerated growth of macrometastasis and negated increased micrometastatic intrahepatic burden. Thus, activated myofibroblasts drive RF-induced tumorigenesis at a cellular level via induction of the HGF/c-MET/STAT3 axis, and can be successfully pharmacologically suppressed.

Background Despite the increasing use of contrast-enhanced mammography (CEM), there are limited data on the evaluation of findings on recombined images and the association with malignancy. Purpose To determine the rates of malignancy of enhancement findings on CEM images in the presence or absence of low-energy findings using the Breast Imaging Reporting and Data System (BI-RADS) lexicon developed for mammography and MRI. Materials and Methods All diagnostic CEM examinations performed at one academic institution between December 2015 and December 2019 had low-energy and recombined images retrospectively. Data were independently reviewed by three breast imaging radiologists with 5-25 years of experience using the BI-RADS mammography and MRI lexicon. Outcome was determined with pathologic analysis or 1-year imaging or clinical follow-up. The χ2 and Fisher exact tests were used for analysis. Results A total of 371 diagnostic CEM studies were performed in 371 women (mean age, 54 years ± 11[SD]). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value of enhancement on CEM images was 95% (104 of 109 [95% CI: 90, 98]), 67% (176 of 262 [95% CI: 61, 73]), 55% (104 of 190 [95% CI: 47, 62]), and 97% (176 of 181 [95% CI: 94, 99]), respectively. Among 190 CEM studies with enhancing findings, enhancing lesions were more likely to be malignant when associated with low-energy findings (26% vs 59%, P < .001). Among enhancement types, mass enhancement composed 71% (99 of 140) of all malignancies with PPV of 63% when associated with low-energy findings. Foci, non-mass enhancement, and mass enhancement without low-energy findings had PPV of 6%, 24%, and 38%, respectively. Neither background parenchymal enhancement nor density was associated with enhancement type (P = .19 and P = .28, respectively). Conclusion Mass enhancement on recombined images using CEM was most commonly associated with malignancy, especially when associated with low-energy findings. Enhancement types were more likely to be benign when not associated with low-energy findings; however, they should still be viewed with suspicion, given the high association with malignancy. © RSNA, 2022 Online supplemental material is available for this article.

OBJECTIVES: The study authors hypothesized that a combination of previously used (path length, translational motions, and time) and novel (rotational sum) motion metrics could be used to analyze learning curves of anesthesiology interns (postgraduate year 1) practicing central venous catheter placement in the simulation setting. They also explored the feasibility of using segmented motion recordings to inform deliberate practice.

DESIGN: A prospective cohort study.

SETTING: A single academic medical center.

PARTICIPANTS: Anesthesiology interns (postgraduate year 1).

INTERVENTIONS: Anesthesiology interns underwent a 2-day training course in which they performed 9 central venous catheter placements, while attached to motion sensors on the dorsum of their dominant hand and ultrasound probe.

MEASUREMENTS AND MAIN RESULTS: Motion metrics were analyzed using generalized estimating equations for both the overall procedure and predefined segments. Five attending anesthesiologists performed 3 trials each for comparison. Overall, there was a negative trend in path length, translational motions, rotational sum, and time (p < 0.001), with the exception of translational motions of the ultrasound probe. Interns reached within 1 standard deviation of the attending anesthesiologists by trials 7-to-8 for most metrics. Segmentation identified specific components of the procedure that were either significantly improved upon or required deliberate practice. The novel metric of rotational sum exhibited a moderate-to-strong positive correlation with other metrics (p < 0.001).

CONCLUSIONS: A comprehensive series of motion metrics was able to describe the learning curves of novices training to perform central venous catheter placement in the simulation setting. Furthermore, it was determined that segmentation may provide additional insight into skill acquisition and inform deliberate practice.

RATIONALE AND OBJECTIVES: To ascertain the perceived obstacles that medical students and Interventional Radiology (IR) residents face performing IR research during training and incorporating research into their future careers.

MATERIALS AND METHODS: The study was reviewed and exempt from Institutional Review Board review. Participants' attitudes and perceived barriers toward performing IR research, and experience with mentorship in IR were assessed using a 27-item survey sent to all members of the Society of Interventional Radiology Resident, Fellow and Student (SIR-RFS, n = 445), and Medical Student Council (SIR-MSC, n = 267) sections between July and September 2020. Descriptive statistics were computed for all assessed categorical variables. Fisher's exact tests were performed to measure the significance of association between categorical variables.

RESULTS: Of the 712 students and residents surveyed, 151 (∼21%) responded. Of respondents, 100% reported that conducting research is important to advancing the field of IR. The highest ranked factors and obstacles to performing IR research were increased clinical demands (67.9%), lack of time (46.2%), lack of institutional support (41.5%), and lack of research experience (35.8%). Interestingly, those with a mentor were more likely to report an interest in pursuing a career in IR compared to those without a mentor (98.6% vs 41.0%, p < 0.0001). Furthermore, those with a mentor were more likely to report an interest in pursuing IR research compared to those without a mentor (32.5% vs 14.4%, p < 0.0001).

CONCLUSION: There are many obstacles to performing IR research. Strong mentorship is an avenue to address these deterrents. The deployment of mentorship programs in IR is needed to ensure trainees can overcome the barriers outlined in this study and successfully pursue research careers in IR.

Abdominal radiology as a field has historically played an important role in the training, research, and performance of image-guided procedures. With the emphasis on increased subspecialization and the more formal and rigorous interventional radiology training programs, the question of the future of image-guided procedures within abdominal radiology is explored. A survey conducted by the Cross-Sectional Interventional Radiology Emerging Technology Commission on members of the Society of Abdominal Radiology showed that image-guided procedures are overwhelmingly being performed by abdominal radiology groups, and the vast majority of programs are training their fellows in this regard. We explore some of the challenges radiology and health care in general may face should abdominal radiologists no longer perform procedures and outline strategies departments can employ to meet the needs of both abdominal and interventional radiologists.

RATIONALE AND OBJECTIVES: In response to COVID-19, our institution implemented three virtual readout systems: a commercial HIPAA compliant web-based video conferencing platform used for screen-sharing (Starleaf), an interactive control sharing system integrated into PACS allowing simultaneous multi-user mouse control over images (Collaborate), and the telephone. Our aim was to assess overall satisfaction with and perceived effectiveness of these virtual readout methods to optimize best practices for the future.

MATERIALS AND METHODS: An IRB-exempt survey was electronically distributed to 64 trainees and 76 attendings at one tertiary-care institution via Survey Monkey. Questions focused on overall satisfaction, perceived effectiveness, technical difficulties, and continued future use of the three virtual readout strategies. Answers were collected with Likert scales, tick boxes, and open-ended questions.

RESULTS: 32/64 trainees (50%) and 32/76 attendings (42%) completed the survey. Trainees and attendings were more satisfied with screen sharing (Starleaf) and perceived it more effective than control sharing (Collaborate) or the telephone (p < 0.0001). Respondents experienced more technical difficulties with control sharing versus screen sharing (p = 0.0004) with a negative correlation between level of technical difficulties and satisfaction with screen sharing (r = -0.50, p < 0.0001) and control sharing (r = -0.38, p = 0.0006). Trainees and faculty supported a combination of in-person and virtual readouts in the future (p < 0.0001).

CONCLUSION: Platforms mirroring in-person readouts, such as Starleaf, are preferred by both trainees and attendings over non-screen sharing platforms such as the telephone. However, technical stability determines satisfaction between similar platforms. Both trainees and attendings support incorporation of virtual readout methods in combination with traditional in-person readouts in the post-COVID-19 era.

BACKGROUND: Routine management after abscess drainage includes CT or fluoroscopic imaging to assess for residual abscess cavity prior to catheter removal. It is unclear whether this practice is necessary in patients without residual infection signs and symptoms.

PURPOSE: To evaluate safety of abscess catheter removal without follow-up imaging in patients without residual clinical or laboratory signs of infection and catheter output < 10 cc/day for 2 consecutive days.

MATERIALS AND METHODS: In this IRB-approved, HIPAA compliant, retrospective study, consecutive patients that underwent percutaneous CT-guided drainage of a single abdominal or pelvic abscess between 01/2015 and 12/2017 in a single tertiary academic institution with or without follow-up imaging prior to catheter removal were included. In our institution, catheters are routinely removed without imaging if there are no clinical (fever, pain) or laboratory (elevated WBC count) signs of infection and catheter output is < 10 cc/day for 2 consecutive days. Patients' and abscess's characteristics, repeat imaging data, and need for re-interventions were obtained through medical records review. Statistical analysis was performed with Fisher's exact test for independent data and Student's t-test for comparison of group means.

RESULTS: 310 consecutive patients (age 56 ± 16 years, 48% female) were included in the study. In 265/310 (85%) patients, no routine follow-up imaging prior to catheter removal was obtained. In 2/265 (0.8%, 95% CI 0.02-0.27%) patients without routine pre-removal imaging, repeat abscess drainage was required 6 and 15 days after catheter removal in patient with perforated appendicitis and after laparoscopic renal cyst decortication, respectively. No patients, 0/45 (0%, 95% CI 0-0.07), that underwent routine imaging without clinical or laboratory signs infection needed to undergo a repeat abscess drainage.

CONCLUSION: There is a low rate (0.8%) of abscess recurrence if percutaneous abscess catheter is removed at the time cessation of drainage without routine imaging in clinically well patient.

BACKGROUND: Four-dimensional (4D) CT localization allows minimally invasive parathyroidectomy as treatment for primary hyperparathyroidism (PHPT), but false positive localization is frequent. We sought to characterize the ability of 4D CT to predict four-gland hyperplasia (HP) based on the size of candidate lesions.

STUDY DESIGN: We retrospectively analyzed patients with PHPT who underwent 4D CT imaging and parathyroidectomy between 2014 and 2020 from a prospectively collected institutional database. The cohort was stratified into two groups, HP vs single adenoma (SA) and double adenoma (DA), based on operative findings and pathology. Logistic regression models assessed the association between the greatest diameter of the dominant candidate lesion on 4D CT and the outcomes of four-gland hyperplasia vs SA and DA.

RESULTS: Among a cohort of 240 patients, 41 were found to have HP, and 199 had adenomas (SA = 155, DA = 44). Patients with HP were less likely to have a preoperative calcium level greater than 1 mg/dL above the upper limit of normal compared with patients with adenomas (63% vs 81%, p = 0.02) and more likely to report symptoms (61% vs 43%, p = 0.04). After adjusting for BMI, we found an estimated 13% reduction in odds of HP for every 1-mm increase in the greatest diameter of dominant candidate lesions identified on 4D CT scan (odds ratio 0.87, 95% CI 0.78 to 0.96, p = 0.009).

CONCLUSIONS: A smaller size of the dominant lesion on 4D CT scan is associated with an increased risk of HP in PHPT. Use of 4D CT imaging localization may provide evidence for differentiating HP from adenomas.