Transient, Image-Guided Gel-Dissection for Percutaneous Thermal Ablation.

Image-guided tumor ablative therapies are mainstay cancer treatment options but often require intra-procedural protective tissue displacement to reduce the risk of collateral damage to neighboring organs. Standard of care strategies, such as hydrodissection (fluidic injection), are limited by rapid diffusion of fluid and poor retention time, risking injury to adjacent organs, increasing cancer recurrence rates from incomplete tumor ablations, and limiting patient qualification. Herein, a "gel-dissection" technique is developed, leveraging injectable hydrogels for longer-lasting, shapeable, and transient tissue separation to empower clinicans with improved ablation operation windows and greater control. A rheological model is designed to understand and tune gel-dissection parameters. In swine models, gel-dissection achieves 24 times longer-lasting tissue separation dynamics compared to saline, with 40% less injected volume. Gel-dissection achieves anti-dependent dissection between free-floating organs in the peritoneal cavity and clinically significant thermal protection, with the potential to expand minimally invasive therapeutic techniques, especially across locoregional therapies including radiation, cryoablation, endoscopy, and surgery.

Retrieval of a Greenfield Inferior Vena Cava Filter Indwelling for 29 Years.

Inferior vena cava (IVC) filters are used to prevent fatal and nonfatal pulmonary embolism in patients who otherwise cannot receive anticoagulation for venous thrombosis. While generally safe and effective, complications can arise, especially after prolonged implantation. Timely retrieval is essential once the indication for insertion has resolved. However, encountering patients with long-standing embedded filters is not uncommon. This case report discusses the successful retrieval of a permanent Greenfield IVC filter after 29 years.

Preventing inadvertent drain removal using a novel catheter securement device.

Percutaneous drains have provided a minimally invasive way to treat a wide range of disorders from abscess drainage to enteral feeding solutions to treating hydronephrosis. These drains suffer from a high rate of dislodgement of up to 30% resulting in emergency room visits, repeat hospitalizations, and catheter repositioning/replacement procedures, which incur significant morbidity and mortality. Using ex vivo and in vivo models, a force body diagram was utilized to determine the forces experienced by a drainage catheter during dislodgement events, and the individual components which contribute to drainage catheter securement were empirically collected. Prototypes of a skin level catheter securement and valved quick release system were then developed. The system was inspired by capstans used in boating for increasing friction of a line around a central spool and quick release mechanisms used in electronics such as the Apple MagSafe computer charger. The device was tested in a porcine suprapubic model, which demonstrated the effectiveness of the device to prevent drain dislodgement. The prototype demonstrated that the miniaturized versions of technologies used in boating and electronics industries were able to meet the needs of preventing dislodgement of patient drainage catheters.

Evaluation of paravertebral blocks in improving post-procedural pain and decreasing hospital admission after microwave ablation of liver tumors.

Although ablations are performed with conscious sedation or general anesthesia, microwave ablations can be painful post procedure. Newer analgesic modalities, including regional blocks, have promoted the proliferation of less invasive anesthesia care for ablative procedures. This study evaluates whether bilateral paravertebral blocks reduce the need for additional analgesics in comparison to unilateral blocks in microwave ablations. In this retrospective study, individuals undergoing microwave ablation who underwent unilateral versus bilateral nerve blocks at a single institution from 2017 to 2019 were compared. Categorical variables were analyzed using Pearson's chi-squared tests. Comparisons of means were completed using multiple T-tests corrected using the Holm-Sidak method with α = 0.05. Regression modeling was used to identify factors related to increased MME (milligram morphine equivalent) usage and post-procedure admission rates. A total of 106 patients undergoing 112 liver MWA procedures were included in this analysis, with patients receiving either a bilateral or unilateral block. Pre-procedural characteristics demonstrated no significant differences in age or gender. Bilateral blocks were associated with decreased usage of gabapentin (14% vs. 0%, p = 0.01) and a lower rate of post-procedure admissions (OR 0.23, p = 0.003). Therefore, when using paravertebral blocks, bilateral blocks are superior to unilateral blocks, as demonstrated by decreased rates of hospital admission and reduced use of systemic neuropathic pain medication. Additionally, reducing post-procedural MME may reduce the rate of admission to the hospital.

An interpretable machine learning model for the prevention of contrast-induced nephropathy in patients undergoing lower extremity endovascular interventions for peripheral arterial disease.

BACKGROUND: Contrast-induced nephropathy (CIN) is a postprocedural complication associated with increased morbidity and mortality. An important risk factor for development of CIN is renal impairment. Identification of patients at risk for acute renal failure will allow physicians to make appropriate decisions to minimize the incidence of CIN. We developed a machine learning model to stratify risk of acute renal failure that may assist in mitigating risk for CIN in patients with peripheral artery disease (PAD) undergoing endovascular interventions. METHODS: We utilized the American College of Surgeons National Surgical Quality Improvement Program database to extract clinical and laboratory information associated with 14,444 patients who underwent lower extremity endovascular procedures between 2011 and 2018. Using 11,604 cases from 2011 to 2017 for training and 2840 cases from 2018 for testing, we developed a random forest model to predict risk of 30-day acute renal failure following infra-inguinal endovascular procedures. RESULTS: Eight variables were identified as contributing optimally to model predictions, the most important being diabetes, preoperative BUN, and claudication. Using these variables, the model achieved an area under the receiver-operating characteristic (AU-ROC) curve of 0.81, accuracy of 0.83, sensitivity of 0.67, and specificity of 0.74. The model performed equally well on white and nonwhite patients (Delong p-value = 0.955) and patients age < 65 and patients age ≥ 65 (Delong p-value = 0.659). CONCLUSIONS: We develop a model that fairly and accurately stratifies 30-day acute renal failure risk in patients undergoing lower extremity endovascular procedures for PAD. This model may assist in identifying patients who may benefit from strategies to prevent CIN.

Student High Value Care Initiative: a Longitudinal Model for Student-Led Implementation and Scholarship.

BACKGROUND: Educating medical trainees to practice high value care is a critical component to improving quality of care and should be introduced at the beginning of medical education. AIM: To create a successful educational model that provides medical students and junior faculty with experiential learning in quality improvement and mentorship opportunities, and produce effective quality initiatives. SETTING: A tertiary medical center affiliated with a medical school in New York City. PARTICIPANTS: First year medical students, junior faculty in hospital medicine, and a senior faculty course director. PROGRAM DESCRIPTION: The Student High Value Care initiative is a longitudinal initiative comprised of six core elements: (1) project development, (2) value improvement curriculum, (3) mentorship, (4), Institutional support, (5) scholarship, and (6) student leadership. PROGRAM EVALUATION: During the first 3 years, 68 medical students and ten junior faculty participated in 10 quality improvement projects. Nine projects were successful in their measured outcomes, with statistically significant improvements. Nine had an abstract accepted to a regional or national meeting, and seven produced publications in peer-reviewed literature. DISCUSSION: In the first 3 years of the initiative, we successfully engaged medical students and junior faculty to create and support the implementation of successful quality improvement initiatives. Since that time, the program continues to offer meaningful mentorship and scholarship opportunities.

Rate of True-Positive Findings of COVID-19 Typical Appearance at Chest CT per RSNA Consensus Guidelines in an Increasingly Vaccinated Population.

Background RSNA consensus guidelines for COVID-19-related chest CT are widely used but, to the knowledge of the authors, their rate of true-positive findings for COVID-19 pneumonia in vaccinated patients has not been assessed. Purpose To assess the rate of true-positive findings of typical appearance for COVID-19 at chest CT by using RSNA guidelines in fully vaccinated patients with polymerase chain reaction (PCR)-confirmed COVID-19 infection compared with unvaccinated patients. Materials and Methods Included were patients with COVID-19 who had typical appearance on chest CT images and one PCR test for COVID-19 with a positive result or two tests with negative results within 7 days of undergoing chest CT between January 2021 and January 2022 at a quaternary academic medical center. True-positive findings were defined as chest CT images interpreted as COVID-19 typical appearance and PCR-confirmed COVID-19 infection within 7 days. Logistic regression models were constructed to quantify the association between PCR results and vaccination status, vaccination status and COVID-19 variants, and vaccination status and number of months. Results Included were 652 patients (median age, 59 years; IQR, 48-72 years; 371 men [57%]) with CT scans classified as typical appearance. Of those patients, 483 (74%) were unvaccinated and 169 (26%) were fully vaccinated. The overall rate of true-positive findings on CT images rated as typical appearance was lower in vaccinated versus unvaccinated patients (70 of 169 [41%; 95% CI: 34, 49] vs 352 of 483 [73%; 95% CI: 69, 77]; odds ratio [OR], 3.8 [95% CI: 2.6, 5.5]; P < .001). Unvaccinated patients were more likely to have true-positive findings on CT images compared with fully vaccinated patients during the peaks of COVID-19 variants Alpha (OR, 16; 95% CI: 6, 42; P < .001) and Delta (OR, 8; 95% CI: 4, 16; P < .001), but no statistical differences were found during the peak of the Omicron variant (OR, 1.7; 95% CI: 0.3, 11; P = .56). Conclusion Fully vaccinated patients with confirmed COVID-19 breakthrough infections had lower rates of true-positive findings of COVID-19 typical appearance at chest CT. © RSNA, 2022 Supplemental material is available for this article.

Erratum: Basivertebral Nerve Ablation.

[This corrects the article DOI: 10.1055/s-0042-1745794.].

Association of Artificial Intelligence-Aided Chest Radiograph Interpretation With Reader Performance and Efficiency.

Importance: The efficient and accurate interpretation of radiologic images is paramount. Objective: To evaluate whether a deep learning-based artificial intelligence (AI) engine used concurrently can improve reader performance and efficiency in interpreting chest radiograph abnormalities. Design, Setting, and Participants: This multicenter cohort study was conducted from April to November 2021 and involved radiologists, including attending radiologists, thoracic radiology fellows, and residents, who independently participated in 2 observer performance test sessions. The sessions included a reading session with AI and a session without AI, in a randomized crossover manner with a 4-week washout period in between. The AI produced a heat map and the image-level probability of the presence of the referrable lesion. The data used were collected at 2 quaternary academic hospitals in Boston, Massachusetts: Beth Israel Deaconess Medical Center (The Medical Information Mart for Intensive Care Chest X-Ray [MIMIC-CXR]) and Massachusetts General Hospital (MGH). Main Outcomes and Measures: The ground truths for the labels were created via consensual reading by 2 thoracic radiologists. Each reader documented their findings in a customized report template, in which the 4 target chest radiograph findings and the reader confidence of the presence of each finding was recorded. The time taken for reporting each chest radiograph was also recorded. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) were calculated for each target finding. Results: A total of 6 radiologists (2 attending radiologists, 2 thoracic radiology fellows, and 2 residents) participated in the study. The study involved a total of 497 frontal chest radiographs-247 from the MIMIC-CXR data set (demographic data for patients were not available) and 250 chest radiographs from MGH (mean [SD] age, 63 [16] years; 133 men [53.2%])-from adult patients with and without 4 target findings (pneumonia, nodule, pneumothorax, and pleural effusion). The target findings were found in 351 of 497 chest radiographs. The AI was associated with higher sensitivity for all findings compared with the readers (nodule, 0.816 [95% CI, 0.732-0.882] vs 0.567 [95% CI, 0.524-0.611]; pneumonia, 0.887 [95% CI, 0.834-0.928] vs 0.673 [95% CI, 0.632-0.714]; pleural effusion, 0.872 [95% CI, 0.808-0.921] vs 0.889 [95% CI, 0.862-0.917]; pneumothorax, 0.988 [95% CI, 0.932-1.000] vs 0.792 [95% CI, 0.756-0.827]). AI-aided interpretation was associated with significantly improved reader sensitivities for all target findings, without negative impacts on the specificity. Overall, the AUROCs of readers improved for all 4 target findings, with significant improvements in detection of pneumothorax and nodule. The reporting time with AI was 10% lower than without AI (40.8 vs 36.9 seconds; difference, 3.9 seconds; 95% CI, 2.9-5.2 seconds; P < .001). Conclusions and Relevance: These findings suggest that AI-aided interpretation was associated with improved reader performance and efficiency for identifying major thoracic findings on a chest radiograph.

Basivertebral Nerve Ablation.

Low back pain is one of the most prevalent musculoskeletal ailments in the United States. Intraosseous radiofrequency ablation of the basivertebral nerve is an effective and durable therapy for low back pain and can be offered to patients who have chronic low back pain of greater than 6 months of duration, failure to respond to noninvasive therapies for 6 months, with either Modic Type I or Type II changes at L3-S1. This article reviews the anatomy and physiology, patient selection, technique, and evidence regarding basivertebral nerve ablation.

Predictors for Nonhome Patient Discharge following Lower Extremity Arterial Interventions.

PURPOSE: To identify the variables associated with patient discharge disposition to optimize postprocedural care and discharge planning following lower extremity arterial interventions for peripheral artery disease (PAD). MATERIALS AND METHODS: The 2014-2017 American College of Surgeons National Surgical Quality Improvement Program database was queried using current procedural terminology codes for endovascular infrainguinal interventions for PAD. The main outcome variable of interest was nonhome discharge. Covariates included patient sociodemographic variables, age quartile (upper quartile, ≥77 years), comorbidities (diabetes, renal disease, bleeding disorder, congestive heart failure [CHF], and chronic obstructive pulmonary disease), presence of an open wound before a procedure, type of procedure, operative time, symptom severity, American Society of Anesthesiologists class, and baseline functional status. Univariate analysis and multivariate logistic regression were performed on Stata/SE 15.1. RESULTS: A total of 3,190 patients met the inclusion criteria, of whom 664 (20.8%) had nonhome discharge. Multivariate regression revealed that age (odds ratio [OR], 1.9 for the upper age quartile [>77 years]; 95% confidence interval [CI], 1.46-2.50), operative time (OR, 1.2 per increase in quartile; 95% CI, 1.09-1.30), preoperative wound (OR, 1.5; 95% CI, 1.24-1.90), renal failure (OR, 1.7; 95% CI, 1.30-2.14), CHF (OR, 2.2; 95% CI, 1.51-3.24), symptom severity (OR, 1.7; 95% CI, 1.46-1.98), and independent functional status (OR, 0.74; 95% CI, 0.59-0.92; P = .007) were associated with nonhome discharge. All P values were ≤.001 unless otherwise stated. CONCLUSIONS: Prolonged procedural time, the presence of preprocedural wound and patient comorbidities, symptomatology, and baseline functional status may be used to identify patients who will require a nonhome discharge and early discharge planning.

Interpretable Machine Learning for the Prediction of Amputation Risk Following Lower Extremity Infrainguinal Endovascular Interventions for Peripheral Arterial Disease.

PURPOSE: Severe peripheral artery disease (PAD) may result in lower extremity amputation or require multiple procedures to achieve limb salvage. Current prediction models for major amputation risk have had limited performance at the individual level. We developed an interpretable machine learning model that will allow clinicians to identify patients at risk of amputation and optimize treatment decisions for PAD patients. METHODS: We utilized the American College of Surgeons National Surgical Quality Improvement Program database to collect preoperative clinical and laboratory information on 14,444 patients who underwent lower extremity endovascular procedures for PAD from 2011 to 2018. Using data from 2011 to 2017 for training and data from 2018 for testing, we developed a machine learning model to predict 30 day amputation in this patient population. We present performance metrics overall and stratified by race, sex, and age. We also demonstrate model interpretability using Gini importance and SHapley Additive exPlanations. RESULTS: A random forest machine learning model achieved an area under the receiver-operator curve (AU-ROC) of 0.81. The most important features of the model were elective surgery designation, claudication, open wound/wound infection, white blood cell count, and albumin. The model performed equally well on white and non-white patients (Delong p-value = 0.189), males and females (Delong p-value = 0.572), and patients under age 65 and patients age 65 and older (Delong p-value = 0.704). CONCLUSION: We present a machine learning model that predicts 30 day major amputation events in PAD patients undergoing lower extremity endovascular procedures. This model can optimize clinical decision-making for patients with PAD.

Primary Care Providers' Knowledge, Attitudes, Beliefs, and Practice Related to Lung Cancer Screening in Five High-Risk Communities in New York City.

Racial/ethnic minorities face stark inequalities in lung cancer incidence, treatment, survival, and mortality compared with US born non-Hispanic Whites. Lung cancer screening (LCS) with low-dose computed tomography (LDCT) is effective at reducing lung cancer mortality in high-risk current and former smokers and is recommended by the US Preventive Services Task Force (USPSTF). This study sought to assess primary care providers' (PCPs') knowledge, attitudes, beliefs, and practice related to LCS and the recent USPSTF guidelines in five high-risk immigrant communities in New York City. We surveyed 83 eligible PCPs between December 2016 and January 2018 through surveys sent by mail, email, and fax, administered by phone or in person. The survey included questions about providers' clinical practice, knowledge, attitudes, and beliefs related to LCS and the USPSTF guidelines. Information about patient demographics, PCPs' training background, and practice type were also collected. Sixty-seven percent of respondents reported that they did not have established guidelines for LCS at their practice, and 52% expressed that "vague" screening criteria influenced their referral processes for LCS. Barriers to LCS with LDCT included concerns that LDCT is not covered by insurance, patients' fears of screening results, and patients' concerns regarding radiation exposure. Targeted educational interventions for both PCPs and patients may increase access to recommended LCS, especially for populations at disproportionate risk for lung cancer.

Integrated Custom Composite Polyetheretherketone/Carbon fiber (PEEK/CF) Vertebral Body Replacement (VBR) in the Treatment of Bone Tumors of the Spine: A Preliminary Report From a Multicenter Study.

STUDY DESIGN: Retrospective, multicenter chart, and radiologic review. OBJECTIVE: To present the first case series of bone tumors of the spine surgically reconstructed with a new custom, fully radiolucent, polyetheretherketone/carbon fiber (PEEK/CF) vertebral body replacement (VBR) integrated system. SUMMARY OF BACKGROUND DATA: Surgical resections of spinal tumors result in large defects and local recurrence remains a concern. Current titanium-based implants adversely affects postoperative imaging, directly affects ability to identify tumor recurrence, and for delivery of radiotherapy treatments. PEEK/CF spinal implants allows for improved tumor surveillance, precise pre-radiation Computed Tomography planning, and reduces interference with post-reconstructive adjuvant radiotherapy. METHOD: Thirteen patients with spinal tumors underwent vertebral body resection and reconstruction with an integrated, fully radiolucent, custom PEEK/CF vertebral body replacement, and radiolucent posterior PEEK/CF screw-rod system and/or radiolucent anterior PEEK/CF plate system. Clinical and radiographic data were tabulated. Need for adjuvant radiotherapy determined based on final tissue histology and extent of surgical margins. Postoperative surveillance imaging were reviewed for local tumor recurrence. RESULTS: The ability to integrate the PEEK/CF VBR connected to either the posterior screw-rod system, or anterior plate system provided immediate stability. The VBR was placed directly on cancellous vertebral body surface in 46.2% of cases. Loosening of the distal, or proximal, aspect of posterior system was seen in 15.4% of cases. There was no clinical or radiographic evidence of VBR migration and subsidence at latest follow up. Local recurrence occurred in one (7.7%) patient. CONCLUSION: This is the first series to describe the use of a fully-radiolucent, integrated, PEEK/CF implant system for spinal tumor reconstruction. The use of a PEEK/CF VBR system integrated to either the anterior plate, or posterior screw-rod system is feasible and allows for superior postoperative surveillance imaging and effective delivery of postoperative adjuvant radiotherapy.Level of Evidence: 4.

Mentorship in Interventional Radiology: Addressing Obstacles to Pursuing Research and Innovation Among IR Trainees.

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.

Gender disparities among medical students choosing to pursue careers in medical research: a secondary cross-sectional cohort analysis.

BACKGROUND: Though the proportion of women in medical schools has increased, gender disparities among those who pursue research careers still exists. In this study, we seek to better understand the main factors contributing to the existing gender disparities among medical students choosing to pursue careers in medical research. METHODS: A secondary cross-sectional cohort analysis of previously published data was conducted using a 70-item survey that was sent to 16,418 medical students at 32 academic medical centers, and was IRB exempt from the need for ethical approval at the University of Illinois at Chicago and the University of Pennsylvania. Data was collected from September 2012 to December 2014. Survey results were analyzed using chi-square tests and Cramer's V to determine gender differences in demographic characteristics (training stage, race/ethnicity, marital status, parental status, financial support, and parental career background), career sector choice, career content choice, specialty choice, foreseeable career obstacles, and perceptions about medical research careers. RESULTS: Female respondents were more likely to be enrolled in MD-only programs, while male respondents were more likely to be enrolled in MD/PhD programs. More male students selected academia as their first-choice career sector, while more female respondents selected hospitalist as their first-choice career sector. More female respondents identified patient care and opportunities for community service as their top career selection factors, while more male respondents identified research and teaching as their top career selection factors. Student loan burden, future compensation, and work/life balance were the most reported obstacles to pursuing a career in medical research. CONCLUSIONS: There are many factors from a medical student's perspective that may contribute to the existing gender disparities in pursuing a career in medical research. While much progress has been made in attracting nearly equal numbers of men and women to the field of medicine, active efforts to bridge the gap between men and women in medical research careers are needed.