Image-Guided Prostate Cryoablation: State-of-the-Art.

Image-guided focal therapy has increased in popularity as a treatment option for patients with primary and locally recurrent prostate cancer. This review will cover the basic indications, evaluation, treatment algorithm, and follow-up for patients undergoing image-guided ablation of the prostate. Additionally, this paper will serve as an overview of some technical approaches to cases so that physicians can familiarize themselves with working in this space. While the focus of this paper is prostate cryoablation, readers will obtain a basic literature overview of some of the additional available image-guided treatment modalities for focal prostate therapy.

Evaluation of an Artificial Intelligence Chatbot for Delivery of IR Patient Education Material: A Comparison with Societal Website Content.

PURPOSE: To assess the accuracy, completeness, and readability of patient educational material produced by a machine learning model and compare the output to that provided by a societal website. MATERIALS AND METHODS: Content from the Society of Interventional Radiology Patient Center website was retrieved, categorized, and organized into discrete questions. These questions were entered into the ChatGPT platform, and the output was analyzed for word and sentence counts, readability using multiple validated scales, factual correctness, and suitability for patient education using the Patient Education Materials Assessment Tool for Printable Materials (PEMAT-P) instrument. RESULTS: A total of 21,154 words were analyzed, including 7,917 words from the website and 13,377 words representing the total output of the ChatGPT platform across 22 text passages. Compared to the societal website, output from the ChatGPT platform was longer and more difficult to read on 4 of 5 readability scales. The ChatGPT output was incorrect for 12 (11.5%) of 104 questions. When reviewed using the PEMAT-P tool, the ChatGPT content scored lower than the website material. Content from both the website and ChatGPT were significantly above the recommended fifth or sixth grade level for patient education, with a mean Flesch-Kincaid grade level of 11.1 (±1.3) for the website and 11.9 (±1.6) for the ChatGPT content. CONCLUSIONS: The ChatGPT platform may produce incomplete or inaccurate patient educational content, and providers should be familiar with the limitations of the system in its current form. Opportunities may exist to fine-tune existing large language models, which could be optimized for the delivery of patient educational content.

Interventional Approach to Portal Vein Thrombosis and Liver Transplantation: State of the Art.

Porto-mesenteric vein thrombosis (PVT) is a well-recognized but uncommon disease entity in patients with and without cirrhosis. Given the complexity of these patients, there are many differing treatment algorithms depending on the individual circumstances of a given patient. The focus of this review is primarily patients with cirrhosis, with an emphasis on liver transplantation considerations. The presence of cirrhosis substantially affects work-up, prognosis, and management of these patients and will substantially affect the patient treatment and have additional implications for prognosis and long-term outcomes. Here, we review the incidence of portal vein thrombosis in known cirrhotic patients, medical and interventional treatment options that are currently used, and, in particular, how to approach cirrhotic patients with PVT who are awaiting liver transplantation.

Deployment of an Interventional Radiology Telemedicine Program During the COVID-19 Pandemic: Initial Experience With 10,056 Visits.

OBJECTIVE: To evaluate the clinical, operational, and financial effects of using telemedicine services in an academic interventional radiology setting during the coronavirus disease 2019 pandemic and to identify potential barriers to equitable telemedicine access for patients. METHODS: Evaluation and management (E&M) data over a 104-week period from September 2019 to August 2021 were reviewed. Data related to the visits were recorded including visit type, billing provider, patient demographic information, Current Procedural Terminology code charged, and reimbursement received. The ZIP code pertaining to the patient's primary residence was matched with median household income from the US Census Bureau. RESULTS: In all, 14,754 E&M encounters were performed over the study period, of which 10,056 were conducted using telemedicine. Twenty-two percent of visits were performed with interactive video; the remainder were performed using audio only. Female patients were more likely than male patients to use interactive video visits for telemedicine encounters (23.7% versus 20.4%, P < .001). Patients availing of video visits (mean age, 58.1 years, SD = 14.0) were also significantly younger than those patients who used audio-only (telephone) encounters (mean age, 62.5 years, SD = 13.3). Patients with private insurance and those living in neighborhoods with higher median household income were more likely to avail of interactive video visits (P < .001). Professional E&M monthly revenue was between 23.3% and 53.2% of peak prepandemic levels (mean 37.7%). CONCLUSION: Telemedicine services allowed for rapid restoration of E&M encounter volumes over the study period. Further work is required to determine the potential implementation barriers to increasing the use of video visits.

Radiofrequency Ablation of Spine Metastases: A Clinical and Technical Approach.

Percutaneous radiofrequency ablation (RFA) is an integral component of the multidisciplinary treatment algorithm for both local tumor control and palliation of painful spine metastases. This minimally invasive therapy complements additional treatment strategies, such as pain medications, systemic chemotherapy, surgical resection, and radiotherapy. The location and size of the metastatic lesion dictate preprocedure planning and the technical approach. For example, ablation of lesions along the spinal canal, within the posterior vertebral elements, or with paraspinal soft tissue extension are associated with a higher risk of injury to adjacent spinal nerves. Additional interventions may be indicated in conjunction with RFA. For example, ablation of vertebral body lesions can precipitate new, or exacerbate existing, pathologic vertebral compression fractures that can be prevented with vertebral augmentation. This article reviews the indications, clinical work-up, and technical approach for RFA of spine metastases.

Factors influencing cumulative radiation dose from percutaneous intra-abdominal abscess drainage in the setting of inflammatory bowel disease.

PURPOSE: Patients with inflammatory bowel disease (IBD) are at risk for intra-abdominal abscesses requiring CT-guided drainage. These patients are at baseline risk of high cumulative radiation exposure from imaging, which may be exacerbated by CT-guided drainage. This study aimed to determine the radiation dose associated with percutaneous drainage in the setting of IBD and identify risk factors associated with high exposure. METHODS: An IRB-approved single-center retrospective study was performed to identify patients with IBD who underwent percutaneous abscess drainage over a 5-year period. An episode of drainage was defined from drain placement to removal, with all intervening procedures and diagnostic CT scans included in the cumulative radiation dose. RESULTS: The mean cumulative effective dose for a drainage episode was 47.50 mSv. The mean duration of a drainage episode was 68.7 days. Patients with a cumulative dose greater than 50 mSv required higher number of follow-up visits compared to patients with less than 50 mSv (6.9 vs. 3.5, p = 0.003*). Patients with higher cumulative dose were also more likely to require drain upsize (54% vs. 13%, p = 0.01*) or additional drain placement (63% vs 24%, p = 0.03*) compared to patients with lower dose. CONCLUSION: Intra-abdominal abscess drainage may be associated with significant cumulative radiation exposure. Requirement of drain upsizing or additional drain placement were associated with higher cumulative radiation dose, which may be related to more severe underlying inflammatory bowel disease.

Utilization of Endovascular and Surgical Treatments for Symptomatic Uterine Leiomyomas: A Population Health Perspective.

PURPOSE: To conduct a population-level analysis of surgical and endovascular interventions for symptomatic uterine leiomyomata by using administrative data from outpatient medical encounters. MATERIALS AND METHODS: By using administrative data from all outpatient hospital encounters in California (2005-2011) and Florida (2005-2014), all patients in the outpatient setting with symptomatic uterine leiomyomata were identified. Patients were categorized as undergoing hysterectomy, myomectomy, uterine artery embolization (UAE), or no intervention. Hospital stay durations and costs were recorded for each encounter. RESULTS: A total of 227,489 patients with uterine leiomyomata were included, among whom 39.9% (n = 90,800) underwent an intervention, including hysterectomy (73%), myomectomy (19%), or UAE (8%). The proportion of patients undergoing hysterectomy increased over time (2005, hysterectomy, 53.2%; myomectomy, 26.9%; UAE, 18.0%; vs 2013, hysterectomy, 80.1%; myomectomy, 14.4%; UAE, 4.0%). Hysterectomy was eventually performed in 3.5% of patients who underwent UAE and 4.1% who underwent myomectomy. Mean length of stay following hysterectomy was significantly longer (0.5 d) vs myomectomy (0.2 d) and UAE (0.3 d; P < .001 for both). The mean encounter cost for UAE ($3,772) was significantly less than those for hysterectomy ($5,409; P < .001) and myomectomy ($6,318; P < .001). Of the 7,189 patients who underwent UAE during the study period, 3.5% underwent subsequent hysterectomy. CONCLUSIONS: The proportion of women treated with hysterectomy in the outpatient setting has increased since 2005. As a lower-cost alternative with a low rate of conversion to hysterectomy, UAE may be an underutilized treatment option for patients with uterine leiomyomata.

Transjugular Intrahepatic Portosystemic Shunts Reduce Variceal Bleeding and Improve Survival in Patients with Cirrhosis: A Population-Based Analysis.

PURPOSE: To investigate from a population health perspective the effects of transjugular intrahepatic portosystemic shunt (TIPS) creation on recurrent variceal bleeding and survival in patients with cirrhosis. MATERIALS AND METHODS: Patients with cirrhosis who presented to outpatient and acute-care hospitals in California (2005-2011) and Florida (2005-2014) with variceal bleeding comprised the study cohort. Patients entered the study cohort at their first presentation for variceal bleeding; all subsequent hospital encounters were then evaluated to determine subsequent interventions, complications, and mortality data. RESULTS: A total of 655,577 patients with cirrhosis were identified, of whom 42,708 (6.5%) had at least 1 episode of variceal bleeding and comprised the study cohort. The median follow-up time was 2.61 years. A TIPS was created in 4,201 (9.8%) of these patients. There were significantly greater incidences of coagulopathy (83.9% vs 72.8%; P < .001), diabetes (45.5% vs 38.8%; P < .001), and hepatorenal syndrome (15.3% vs 12.5%; P < .001) in TIPS recipients vs those without a TIPS. Following propensity-score matching, TIPS recipients were found to have improved overall survival (82% vs 77% at 12 mo; P < .001) and a lower rate of recurrent variceal bleeding (88% vs 83% recurrent bleeding-free survival at 12 months,; P < .001) than patients without a TIPS. Patients with a TIPS had a significant increase in encounters for hepatic encephalopathy vs those without (1.01 vs 0.49 per year; P < .001). CONCLUSIONS: TIPS improves recurrent variceal bleeding rates and survival in patients with cirrhosis complicated by variceal bleeding. However, TIPS creation is also associated with a significant increase in hepatic encephalopathy.

Association of Inferior Vena Cava Filter Placement With Rates of Pulmonary Embolism in Patients With Cancer and Acute Lower Extremity Deep Venous Thrombosis.

Importance: Venous thromboembolism is the second overall leading cause of death for patients with cancer, and there is an approximately 2-fold increase in fatal pulmonary embolism (PE) in patients with cancer. Inferior vena cava (IVC) filters are designed to prevent PE, but defining the appropriate use of IVC filters in patients with cancer remains a substantial unmet clinical need. Objective: To evaluate the association of IVC filters with the development of PE in patients with cancer and deep venous thrombosis (DVT). Design, Setting, and Participants: A population-based cohort study was conducted using administrative data on 88 585 patients from the state inpatient databases for California (2005-2011) and Florida (2005-2014). Based on diagnostic and procedure codes, patients with cancer and acute lower extremity DVT were identified. All subsequent hospital visits for these patients were evaluated for the placement of an IVC filter, the development of new PE, the development of new DVT, and in-hospital mortality. Data analysis was performed from September 1 to December 1, 2019. Exposures: Placement of an IVC filter. Main Outcomes and Measures: The association of IVC filter placement with rates of new PE and DVT was estimated using a propensity score matching algorithm and competing risk analysis. Results: The study cohort comprised 88 585 patients (45 074 male; median age, 71.0 years [range, 1.0-104.0 years]) with malignant neoplasms who presented to a health care institution with a diagnosis of acute lower extremity DVT. Of these patients, 33 740 (38.1%) underwent IVC filter placement; patients with risk factors such as upper gastrointestinal bleeding (odds ratio, 1.32; 95% CI, 1.29-1.37), intracranial hemorrhage (odds ratio, 1.21; 95% CI, 1.19-1.24), and coagulopathy (odds ratio, 1.09; 95% CI, 1.08-1.10) were more likely to receive an IVC filter. A total of 4492 patients (5.1%) developed a new PE after their initial DVT diagnosis. There was a significant improvement in PE-free survival for these patients compared with those who did not receive IVC filters across the full, unbalanced study cohort as well as after propensity score matching and competing risk analysis (hazard ratio, 0.69; 95% CI, 0.64-0.75; P < .001). Furthermore, IVC filter placement reduced the development of PE in patients with very high-risk malignant neoplasms (eg, pancreaticobiliary cancer), high-risk malignant neoplasms (eg, lung cancer), and low-risk malignant neoplasms (eg, prostate cancer). After accounting for anticoagulation use and imbalanced risk factors, IVC filter placement did not increase the risk of new DVT development. Conclusions and Relevance: This study suggests that, for patients with cancer and DVT and bleeding risk factors, IVC filter placement is associated with an increased rate of PE-free survival.

Magnetic resonance imaging/transrectal ultrasonography fusion guided seed placement in a phantom: Accuracy between 2-seed versus 1-seed strategies.

PURPOSE: To investigate whether the 2-seed placement per Magnetic Resonance Imaging (MRI) suspicious lesion yields a higher seed placement accuracy than a 1-seed strategy on a phantom. METHODS: Eight olives embedded in gelatin, each simulating a prostate, underwent MRI. Three virtual spherical lesions (3, 5, and 8 mm diameters) were marked in each olive on the MRI images and co-registered to the MRI/Transrectal Ultrasonography (TRUS) fusion biopsy system. Two radiologists placed 0.5 mm fiducials, targeting the center of each virtual lesion under fusion image guidance. Half of the 8 olives in each phantom were assigned either to the 1-seed or 2-seeds per lesion strategy. Post-procedure Computed Tomography (CT) images identified each seed and were fused with MR to localize each virtual lesion and collected the seed placement error - distance between the virtual target and the corresponding seed (using the closer seed for the 2-seed strategy). Seed placement success is defined as fiducial placement within a lesion boundary. RESULTS: Each operator repeated the procedure on three different phantoms, and data from 209 seeds placed for 137 lesions were analyzed, with an overall error of 3.03 ±â€¯1.52 mm. The operator skill, operator phantom procedural experience, lesion size, and number of seeds, were independently associated with the seed placement error. Seed placement success rate was higher for the 2-seed group compared to 1-seed, although the difference was not statistically significant. CONCLUSIONS: Placing 2 seeds per MRI lesion yielded a significantly lower error compared to 1-seed strategy, although seed placement success rate was not significantly different.

Changes in inferior vena cava filter placement and retrieval practice patterns from a population health perspective.

PURPOSE: Inferior vena cava (IVC) filters are placed to reduce venous thromboembolism (VTE)-related morbidity and mortality, though the evidence supporting this practice is limited. In 2010, the Food and Drug Administration (FDA) released a device safety advisory due to the risk of filter migration, fracture, and thrombosis with long-term use. The purpose of this study was to evaluate trends and predictors for IVCF placement and retrieval over a 10-year time period from a population health perspective. MATERIALS AND METHODS: De-identified patient information from the State Inpatient Databases (SID) and the States Ambulatory Surgery and Services Databases (SASD) for Florida and California were used to identify all patients who underwent IVC filter placement from 2005 to 2014 and 2005 to 2011, respectively. Hospital practice patterns were assessed as a function of time as well as IVC filter placement and retrieval volume. Temporal trends were evaluated for statistical significance using the Cochran-Armitage test. RESULTS: A total of 181,260 IVC filters were placed in 178,327 patients over the study period. IVC filter placements peaked in 2010; following the FDA advisory in 2010, however, IVC filter placements monotonically decreased each subsequent year. The proportion of IVCF placement patients with both acute DVT and PE (17.6% vs 11.8%, P < 0.001) at the time of hospitalization increased; likewise, the proportion of IVCF patients with acute DVT or PE with a concomitant acute contraindication to anticoagulation at the time of hospitalization increased as well following 2010 (17.0% vs 11.9%, P < 0.001). From 2005 to 2014, there was a continual increase in both filter retrieval procedures as well overall percentage of filters retrieved. However, estimated retrieval rates remained low, with a retrieval rate of less than 6% in 2014. CONCLUSION: Following the FDA warning in 2010, there was a significant decrease in IVC filter placements, with filter placements more frequently performed in patients with poorer health. While retrieval rates increased over time, they remained low.

Implementing Virtual and Augmented Reality Tools for Radiology Education and Training, Communication, and Clinical Care.

Advances in virtual immersive and augmented reality technology, commercially available for the entertainment and gaming industry, hold potential for education and clinical use in medicine and the field of medical imaging. Radiology departments have begun exploring the use of these technologies to help with radiology education and clinical care. The purpose of this review article is to summarize how three institutions have explored using virtual and augmented reality for radiology.

A Low-Cost Highly Configurable Phantom for Simulation of Imaging-Guided Endocavitary Procedures.

We developed a method to create customizable phantoms suitable for endocavitary imaging and interventional research, based on the fabrication of an acrylic phantom mold, and development of a phantom matrix composed of gelatin, agar, graphite particles, and propanol. Our phantom was mechanically stable, easily fabricated, and highly adjustable, and its ultrasound (US) and magnetic resonance imaging (MRI) scans showed the qualification for the procedure guidance compared with the human prostate image using the same US system. To test the feasibility of the phantom for the research, the seeds placement guided by MRI/US fusion was performed, and the overall test error (distance from the seed center to the virtual lesion center in olives) was 2.59 ± 0.59 mm. We have created a simple, low-cost, configurable, gelatin-based phantom and tested its feasibility for simulating endorectal interventional US procedures. The design of the phantom mold and matrix is likely to be useful to the broader medical training community, and the preliminary data from the experiment of MRI/US-guided seeds placement showed its potential to test the clinical hypothesis in US research.

Radiation Dose and Risk Estimates of CT-Guided Percutaneous Liver Ablations and Factors Associated with Dose Reduction.

PURPOSE: To determine the radiation dose associated with CT-guided percutaneous liver ablations and identify potential risk factors that result in higher radiation doses. MATERIALS AND METHODS: Between June 2011 and June 2015, 245 consecutive patients underwent 304 CT-guided liver ablation treatments. Patient demographics, tumor characteristics and procedural parameters were identified and analyzed. The peak skin dose and effective dose were assessed for each procedure. Excess relative risk related to radiation effects was calculated. A logistic regression model was prepared by means of stepwise logistic regression to identify variables predictive of increased radiation exposure. RESULTS: Tumor ablations were performed with microwave (n = 220), radiofrequency (n = 74) or irreversible electroporation (IRE) (n = 10). The mean peak skin dose for ablations was 239.2 ± 136.4 mGy, and the mean effective dose was 36.6 ± 22.3 mSv. Of the patient and procedural parameters that were analyzed, increasing weight, use of intravenous contrast and/or hydrodissection during the procedure, together with treatment of multiple lesions in the same sitting were all associated with higher radiation exposure. The mean increase in the absolute risk of fatal malignancy from a single procedure was 0.18% (range 0.02-0.9%). No deterministic skin changes were identified in the patient cohort. CONCLUSION: The overall risk of stochastic and deterministic effects from radiation associated with CT-guided ablations is low compared with other inherent procedural complications. This study identifies several factors that are associated with higher radiation dose in percutaneous liver ablation procedures.

Decision Making: Thermal Ablation Options for Small Renal Masses.

Renal cell carcinoma is a relatively common tumor, with an estimated 63,000 new cases being diagnosed in the United States in 2016. Surgery, be it with partial or total nephrectomy, is considered the mainstay of treatment for many patients. However, those patients with small renal masses, typically less than 3 to 4 cm in size who are deemed unsuitable for surgery, may be suitable for percutaneous thermal ablation. We review the various treatment modalities, including radiofrequency ablation, microwave ablation, and cryoablation; discuss the advantages and disadvantages of each method; and review the latest data concerning the performance of the various ablative modalities compared with each other, and compared with surgery.

Long-Term Outcomes Following Percutaneous Cholecystostomy Tube Placement for Treatment of Acute Calculous Cholecystitis.

INTRODUCTION: Percutaneous cholecystostomy tube (PCT) placement is considered a safe alternative to cholecystectomy for the treatment of acute calculous cholecystitis (ACC), but data regarding long-term outcomes following PCT are limited. METHODS: We retrospectively reviewed our institutional experience of patients undergoing PCT for ACC between 1997 and 2015. Recurrent biliary events were defined as cholecystitis, cholangitis, or gallstone pancreatitis. RESULTS: PCT was placed for 288 patients with ACC. Mean age and age-adjusted Charlson comorbidity index were 72 ± 15 years and 5.3 ± 2.4, respectively. Following PCT placement, 91% of patients successfully resolved their episode of ACC. PCT dysfunction occurred in 132 patients (46%), with 80 patients (28%) requiring re-intervention, while 7% developed procedure-related complications. Interval cholecystectomy reduced the risk of recurrent biliary events to 7% from 21% (p = 0.002). Cholecystectomy was completed laparoscopically in 45% of patients receiving an interval operation vs. 22% of those undergoing urgent surgery for PCT failure or recurrent biliary event (p = 0.03). CONCLUSIONS: PCT placement is a highly successful treatment for acute calculous cholecystitis and is associated with low complication rate, but high rate of tube dysfunction requiring frequent re-intervention. Interval cholecystectomy is associated with a decreased likelihood of recurrent biliary events and increased likelihood of successful laparoscopic completion.

Air Embolism: Diagnosis, Clinical Management and Outcomes.

Air embolism is a rare but potentially fatal complication of surgical procedures. Rapid recognition and intervention is critical for reducing morbidity and mortality. We retrospectively characterized our experience with air embolism during medical procedures at a tertiary medical center. Electronic medical records were searched for all cases of air embolism over a 25-year period; relevant medical and imaging records were reviewed. Sixty-seven air embolism cases were identified; the mean age was 59 years (range, 3-89 years). Ninety-four percent occurred in-hospital, of which 77.8% were during an operation/invasive procedure. Vascular access-related procedures (33%) were the most commonly associated with air embolism. Clinical signs and symptoms were related to the location the air embolus; 36 cases to the right heart/pulmonary artery, 21 to the cerebrum, and 10 were attributed to patent foramen ovale (PFO). Twenty-one percent of patients underwent hyperbaric oxygen therapy (HBOT), 7.5% aspiration of the air, and 63% had no sequelae. Mortality rate was 21%; 69% died within 48 hours. Thirteen patients had immediate cardiac arrest where mortality rate was 53.8%, compared to 13.5% (p = 0.0035) in those without. Air emboli were mainly iatrogenic, primarily associated with endovascular procedures. High clinical suspicion and early treatment are critical for survival.