Percutaneous cryoablation of 100 anterior renal tumors: safety and technical success.

PURPOSE: To assess the safety, technical success, and clinical outcomes of percutaneous cryoablation (PCA) in patients with anterior renal tumors. METHODS: A retrospective analysis of patients with anterior renal tumors, defined as tumors at or anterior to the level of the renal pelvis, treated with CT-guided PCA from 2008 to 2022. Summary statistics included demographics and baseline tumor attributes. Treatment and follow-up metrics included primary and secondary technical success, adverse events (AEs) according to the SIR classification, local recurrence, overall survival (OS), and cancer-specific survival (CSS)). 100 patients (60 males; mean age: 63, mean BMI: 33, mean Charlson comorbidity index:6) with 100 anterior renal tumors were included. RESULTS: 78% of tumors were T1a and 22% T1b with mean maximal tumoral dimension of 29 mm (range: 6-62 mm) and mean distance to nearest critical structure 9 mm (range: 0-40 mm). Mean follow-up was 20.9 months (range: 3-103). 28% of PCAs required hydrodissection. Technical success was achieved in 92% of patients; with six remaining patients undergoing successful repeat PCA (secondary technical success: 98%). The remaining two patients without primary technical success were either surveilled or had a benign pathology on resulted concomitant biopsy. Four patients (4%) had major AEs (hemorrhage requiring prolonged admission, transfusion, or embolization (n = 3), perinephric abscess requiring drainage (n = 1)) and 27% had minor AEs. Eight patients (8%) had recurrence with a one-year OS of 94% and CSS of 100%. All recurrences underwent repeat ablation without additional recurrence and 3/8 (38%) were T1b and 5/8 (63%) were T1a tumors. CONCLUSION: PCA of anterior renal tumors can be performed safely with high rates of technical and oncologic success.

Eye Motion Tracking for Medical Image Interpretation Training.

INTRODUCTION: The significance of Eye Motion Tracking in aiding learners in training search patterns, pattern recognition, and efficiently using their gaze in terms of time and scanning distribution has been highlighted in the USAF Pilot Training Next initiative. METHODS: The innovation described further builds on this concept in the realm of medical imaging and the provision of real-time feedback of eye direction and gaze duration. RESULTS: This real-time indicator enables the trainer to adapt verbal queueing of the trainee in a personalized manner to improve knowledge transfer, and to increase the confidence of the trainer and trainee in the competency of the trainee. The initial experiment data set included bone radiographs, digital subtraction angiograms, and computed tomography images. DISCUSSION: Preliminary results and formative feedback from participants was encouraging with expert viewers able to use Eye Motion Tracking to successfully guide novice readers through search and gaze protocol patterns of the medical images.

Uterine Vascular Anomalies: Management and Treatment Overview.

Uterine vascular anomalies (UVAs), while rare, can result in severe, life-threatening hemorrhage. An understanding of the presentation and management options for UVAs is important for interventional radiologists to appropriately evaluate and care for these patients. The authors propose a standardized terminology for UVAs to avoid confusion and conflating congenital from acquired vascular lesions, which have a different pathophysiology. Limited high-level evidence and no definitive guidelines for UVA management exist, although endovascular treatment with uterine artery embolization has generally become the first-line approach for symptomatic or persistent UVAs with high technical and clinical success rates. There is also no consensus on the optimal embolization technique; the authors propose an initial approach to first embolize the dominant uterine artery supplying the UVA with gelatin sponge, with the option to embolize the contralateral side at the time of initial embolization if there is persistent supply (avoiding bilateral empiric embolization). Repeat embolization is feasible and recommended in the setting of recurrence, and both clinical and imaging follow-up is important. Ultimately, a multidisciplinary approach with individualized patient management is needed, particularly in the face of a lack of consensus guidelines for the management of symptomatic UVAs.

Short-term outcomes of uterine artery embolization for urgent or emergent abnormal uterine bleeding.

PURPOSE: To evaluate the outcomes of uterine artery embolization (UAE) for patients with urgent or emergent abnormal uterine bleeding (AUB). MATERIALS AND METHODS: Retrospective review of all patients from 1/2009-12/2020 who were treated urgently or emergently with UAE for AUB. Urgent and emergent cases were defined as those requiring inpatient admissions. Demographic data were collected for each patient including hospitalizations related to bleeding and length of stay (LOS) for each hospitalization. Hemostatic interventions other than UAE were collected. Hematologic data were collected before and after UAE including hemoglobin, hematocrit, and transfusion products. Data specific to the UAE procedure included complication rates, 30-day readmission, 30-day mortality, embolic agent, site of embolization, radiation dose, and procedure time. RESULTS: 52 patients (median age: 39) underwent 54 urgent or emergent UAE procedures. The most common indications for UAE were malignancy (28.8%), post-partum hemorrhage (21.2%), fibroids (15.4%), vascular anomalies (15.4%), and post-operative bleeding (9.6%). There were no procedure-related complications. Following UAE, 44 patients (84.6%) achieved clinical success and required no additional intervention. Packed red blood cell transfusion decreased from a mean of 5.7 to 1.7 units (p < 0.0001). Fresh frozen plasma transfusion decreased from a mean of 1.8 to 0.48 units (p = 0.012). 50% of patients received a transfusion prior to UAE, while only 15.4% were transfused post-procedure (p = 0.0001). CONCLUSIONS: Emergent or urgent UAE is a safe and effective procedure to control AUB hemorrhage secondary to a variety of etiologies.

Diagnosis and Management of Pelvic Venous Disorders: AJR Expert Panel Narrative Review.

Pelvic venous disorders (PeVD), previously known by various imprecise terms including pelvic congestion syndrome, have historically been underdiagnosed as a cause of chronic pelvic pain (CPP), a significant health problem associated with reduced quality of life. However, progress in the field has helped to provide heightened clarity with respect to definitions relating to PeVD, and evolution in algorithms for PeVD workup and treatment has been accompanied by new insights into the causes of a pelvic venous reservoir and associated symptoms. Ovarian and pelvic vein embolization, as well as endovascular stenting of common iliac vein compression, should be considered as management options for PeVD. Both treatments have been shown to be safe and effective for patients with CPP of venous origin, regardless of age. Current therapeutic protocols for PeVD exhibit significant heterogeneity owing to limited prospective randomized data and evolving understanding of the factors driving successful outcomes; forthcoming clinical trials are anticipated to improve understanding of CPP of venous origin as well as algorithms for PeVD management. This Expert Panel Narrative Review provides a contemporary update relating to PeVD, summarizing the entity's current classification, diagnostic workup, endovascular treatments, management of persistent or recurrent symptoms, and future research directions.

Interventional Radiology in Obstetrics and Gynecology: Updates in Women's Health.

Interventional radiology has had an expanding role in women's health over the past few decades, with recent accelerated growth and development. Interventional radiology is fundamental in the treatment of multiple conditions that affect women, including pelvic venous disease, uterine fibroids, and adenomyosis, and in postpartum management. Patient workup, classification, and treatment techniques have continued to evolve as interventional radiology has become more prevalent in the treatment of patients affected by these conditions. The authors provide a review of the pathophysiology of, patient workup for, and treatment of pelvic venous disease and uterine artery embolization for various disease processes. The authors also highlight updates from the past 5-10 years in diagnosis, classification, and treatment strategies. © RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Transarterial embolization of T1b and T2a renal cell carcinoma prior to percutaneous cryoablation: a retrospective comparative study.

PURPOSE: To compare outcomes in patients with T1b and T2a renal cell carcinoma (RCC) treated with percutaneous cryoablation (PCA) who underwent transarterial embolization (TAE) of the RCC prior to PCA (TAE + PCA) to patients who were treated with PCA alone. METHODS: Retrospective review of all adult patients with T1b (4.1-7 cm) and T2a (7.1-10 cm) RCC treated with PCA from 2008 to 2021. Data collected included age, sex, tumor diameter, RENAL nephrometry score, technical success, adverse events (AEs), changes in serum creatinine, local control, and recurrence rates. A p value of 0.05 was considered the threshold for statistical significance. RESULTS: 13 patients with 13 RCCs (mean age: 72.7 ± 10.4; 54% male) and 35 patients with 37 RCCs (mean age: 66.7 ± 10.6; 60% male) were included in the TAE + PCA and PCA groups, respectively. The TAE + PCA group had larger mean tumor diameter (5.7 ± 1.1 cm vs. 4.7 ± 0.6 cm; p < 0.0001) and higher mean RENAL nephrometry score (8.9 ± 1.1 vs. 7.8 ± 1.5; p = 0.02). There were no differences between the groups with respect to technical success of PCA (p = 0.46), local tumor control (p = 0.3), or mean number of procedures to achieve local tumor control (p = 0.85). Mean increase in serum creatinine was not significantly different between the two groups (p = .63). Major AEs were similar between the groups (p = 1); however, the TAE + PCA group had no major hemorrhagic AEs while the PCA alone group had three (8.3%). CONCLUSION: TAE + PCA in patients with T1b or T2 RCC is technically feasible without significant added detriment to renal function. This combined approach may help to reduce hemorrhagic AEs but larger patient cohorts are needed.

Nononcologic Embolization.

The scope of conditions managed by embolization, which was initially used for the treatment of hemorrhage and vascular malformations, is constantly expanding. Apart from oncologic indications, embolization is used to treat a wide range of benign pathology, including uterine fibroids and benign prostatic hyperplasia. While various particulate embolic agents are successfully used for benign embolization, there is growing evidence that unique properties of these may result in different outcomes. This article reviews available evidence comparing various particles used for uterine fibroid embolization and prostate artery embolization. In addition, we provide an overview of periprocedural pharmacology and protocols facilitating same-day discharge for these interventions.

External Validation of the Percutaneous Renal Ablation Complexity Scoring System in Patients Undergoing Percutaneous Cryoablation or Microwave Ablation of Renal Tumors.

PURPOSE: To assess the ability of the Percutaneous Renal Ablation Complexity (P-RAC) scoring system to predict procedural complexity or adverse events (AEs) in adult patients undergoing percutaneous thermal ablation of renal tumors. MATERIALS AND METHODS: A retrospective review of 240 consecutive adult patients who underwent percutaneous thermal renal ablation from 2004 to 2018 was conducted. The P-RAC score was calculated for each renal tumor and procedural complexity recorded. A correlation coefficient was calculated for the P-RAC score and both the number of probes used and procedural duration. Receiver operating characteristic curves assessed the score's ability to predict the use of adjunctive techniques and/or major AEs, classified according to the Society of Interventional Radiology guidelines. RESULTS: For the entire cohort, there was a weak correlation between P-RAC scores and both the number of probes used (r = 0.31; P < .001) and procedural duration (r = 0.18; P = .03). When evaluating only patients treated with microwave ablation (MWA), no correlation between P-RAC scores and either the number of probes (P = .7) used or procedural duration (P = .4) was found. The area under the curve (AUC) for the P-RAC score to predict the use of adjunctive techniques was 0.55 and 0.53 for the entire cohort and MWA group, respectively. The AUC for the P-RAC score to predict major AEs was 0.70, 0.71, and 0.73 for the entire cohort, MWA group, and cryoablation group, respectively. CONCLUSIONS: The P-RAC scoring system is limited in its ability to predict percutaneous thermal renal tumor ablation procedural complexity, especially in patients treated with MWA. The scoring system may have a role in identifying patients at risk of major AEs.

Radiological correlation of mechanism of intravascular migration of the ventriculoperitoneal shunt and technical considerations for endovascular retrieval.

Migration of ventriculoperitoneal shunt into the pulmonary artery is a rare complication that can lead to shunt malfunction and cardiopulmonary complications. This case illustrates the significance of accidental transvenous placement of the shunt. Identification of the transvenous course of the catheter on cross sectional imaging can predict future catheter migration and also aid at surgical extraction. Formation of knot within the distal portion of the shunt catheter during migration or endovascular retrieval can occur, therefore measures to retrieve with knot and adhesions should be factored in before.

Uterine Artery Embolization for Symptomatic Adenomyosis: Proceedings from a Society of Interventional Radiology Foundation Research Consensus Panel.

Adenomyosis poses an important diagnostic and therapeutic challenge in women's health because of a variety of clinical/imaging presentations and frequent coexistence with other benign gynecologic conditions. In recent years, uterine artery embolization (UAE) for the treatment of adenomyosis has shown encouraging and favorable outcomes and long-term symptom improvement. To expand the current understanding of adenomyosis pathophysiology, imaging diagnostic criteria, and treatment outcomes, the Society of Interventional Radiology Foundation gathered a multidisciplinary Research Consensus Panel with experts from diverse backgrounds. The topics addressed were centered around the following: (i) the clinical presentation and imaging findings to diagnose adenomyosis; (ii) the currently available medical, interventional, and surgical treatment options; and (iii) existing literature for and experiences with UAE in symptomatic disease. The panel acknowledged that before the pursuit of a clinical trial, it would be necessary to first evaluate the imaging criteria for adenomyosis and correlate them with pathology and symptoms to establish a noninvasive imaging classification system. Second priority was given to the development of a quality of life questionnaire to assess patient outcomes following treatment. The third priority was the performance of a prospective clinical trial comparing UAE with medical therapy, which would help establish UAE in the treatment algorithm and societal guidelines for symptomatic adenomyosis.

Uterine Artery Embolization for Adenomyosis.

Adenomyosis is a benign gynecologic condition of the uterus similar to uterine leiomyoma (fibroids), but with different pathophysiology and prevalence. The treatment algorithms for symptomatic adenomyosis are not as established as for uterine fibroids and other gynecologic conditions. Uterine artery embolization (UAE) is a well-recognized treatment for symptomatic uterine fibroids. This minimally invasive therapy has been likewise effective for symptomatic adenomyosis but with nuances in UAE protocol and outcomes. There is also less quality evidence to garner support for generalized use of the procedure for symptomatic adenomyosis. Many factors contribute to this lack of data, and efforts to clarify the utility of UAE in adenomyosis will need to address a classification system and standardization of technique.

Development of Research Agenda in Prostate Artery Embolization: Summary of Society of Interventional Radiology Consensus Panel.

PURPOSE: To summarize the Society of Interventional Radiology Foundation's Research Consensus Panel development of a research agenda on prostate artery embolization (PAE). MATERIALS AND METHODS: PAE for the treatment of lower urinary tract symptoms has been shown to be safe and effective in decreasing symptoms and prostate size. Lack of randomized controlled trials (RCTs) on PAE in the United States has prevented inclusion in American Urologic Association guideline recommendations for treatment of lower urinary tract symptoms resulting from benign prostatic hyperplasia. Recognizing the need for well-designed trials, the SIR Foundation funded a Research Consensus Panel to prioritize a research agenda. The panel included interventional radiologists, urologists, SIR Foundation leadership, and industry representatives. The goal of the meeting was to discuss weaknesses with current data and study design for development of US trials to report long-term outcomes data. RESULTS: Final consensus on a research design could not be made because the group was split on 3 research designs: (i) RCT of PAE versus sham with crossover of the sham group. (ii) RCT of PAE versus simple prostatectomy. (iii) RCT of PAE versus holmium laser enucleation of the prostate/thulium laser enucleation of the prostate. The panel recommended a nonindustry-funded registry to obtain real-world data. CONCLUSIONS: Level 1 data are required to be included in the American Urologic Association guidelines for treatment of benign prostatic hyperplasia. Because of concerns with all 3 study designs, the panel did not reach a consensus. Further meetings are planned with the panel to select among these research designs.

Bridging Hepatocellular Carcinoma to Transplant: Transarterial Chemoembolization Response, Tumor Biology, and Recurrence after Transplantation in a 12-Year Transplant Cohort.

PURPOSE: To evaluate tumor response to transarterial chemoembolization as well as biologic characteristics of the tumor as predictors of recurrence after transplantation in patients with hepatocellular carcinoma (HCC) who were bridged or down-staged to liver transplantation. MATERIALS AND METHODS: An institutional review board-approved, Health Insurance Portability and Accountability Act-compliant, single-institution retrospective analysis was performed on all patients with HCC who were treated with the use of conventional transarterial chemoembolization or transarterial chemoembolization with drug-eluting embolics (DEE) over a 12-year period and who subsequently underwent liver transplantation (n = 142). Treatment response was based on modified Response Evaluation Criteria in Solid Tumors (mRECIST) imaging criteria and then correlated with tumor characteristics and recurrence. Of the 142 patients followed after transplantation, 127 had imaging after transarterial chemoembolization but before transplantation. Imaging response and post-transplantation recurrence were correlated with patient demographics, liver function, and tumor morphology. HCC recurred in 9 patients (mean time from transplantation, 526 days). Recurrence was analyzed with the use of univariate and multivariate statistics. Kaplan-Meier recurrence-free survival curves were calculated based on immediate imaging response before transplantation with the use of the log-rank test. RESULTS: Before transplantation, 57% of patients (72/127) demonstrated complete response (CR) and 24% (31/127) showed partial response (PR). Complete pathologic necrosis occurred in 54% (39/72) of CR patients and 20% (6/31) of PR patients. Poor treatment response, defined as stable disease (SD) or progressive disease (PD), occurred in 18% of patients (24/127) before transplantation and was present in 67% of cases of recurrence (6/9; P < .001). Post-transplantation recurrence was present in 1.4% of patients (1/71) with CR and in 6.5% of patients (2/31) with PR. In patients with SD after transarterial chemoembolization, HCC recurred in 18.8% of transplant patients (3/16) and in 43% of patients (3/7) with PD. Larger pretreatment tumor size (P = .05), higher Child-Pugh score (P = .002), higher tumor grade at explantation (P = .04), and lymphovascular invasion at explantation (P = .008) also were associated with increased incidence of post-transplantation recurrence. CONCLUSIONS: Poor tumor response to transarterial chemoembolization before transplantation identifies patients at increased risk for post-transplantation recurrence.

Comparison of Cone-Beam Tomography and Cross-Sectional Imaging for Volumetric and Dosimetric Calculations in Resin Yttrium-90 Radioembolization.

PURPOSE: To compare the use of cone-beam computed tomography versus contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) in the calculation of liver volume and planned dose for yttrium-90 radioembolization. MATERIALS AND METHODS: The study retrospectively assessed 47 consecutive patients who underwent resin Y-90 radioembolization consecutively over a 2-year period at a single center. Volume calculation software was used to determine perfused lobar liver volumes from cone-beam CT (CBCT) images obtained during mapping angiography. CBCT-derived volumes were compared with perfused lobar volume derived from contrast-enhanced CT and MRI. Nominal activities as determined by the SIR-Spheres Microspheres Activity Calculator were similarly calculated and compared using both CBCT and conventionally acquired volumes. RESULTS: A total of 82 hepatic lobes were assessed in 47 patients. The mean percentage difference between combined CT-MRI- and CBCT-derived calculated lobar volumes was 25.3% (p = 0.994). The mean percentage difference in calculated dose between the two methods was 21.8 ± 24.6% (p = 0.42). Combined left and right lobar CT-derived dose difference was less than 10% in 22 lobes, between 10 and 25% in 20 lobes, between 25 and 50% in 13 lobes and greater than 50% in 5 lobes. Combined left and right lobar MRI-derived dose difference was less than 10% in 11 lobes, between 10 and 25% in 7 lobes, between 25 and 50% in 2 lobes and greater than 50% in 1 lobe. CONCLUSIONS: Although volume measurements derived from CT/MRI did not differ significantly from those derived from CBCT, variability between the two methods led to large and unexpected differences in calculated dose.

Uterine artery embolization: A review of current concepts.

Uterine artery embolization (UAE) has gained traction as a safe and effective treatment modality for symptomatic uterine leiomyomata since its introduction nearly two decades ago. This review includes an overview of current concepts with regard to patient selection, technique, and outcomes following UAE. Specific topics also include the impact of this procedure on fertility and pregnancy, the emerging role of UAE in the treatment of adenomyosis, and how UAE compares with surgical intervention for the treatment of symptomatic leiomyomata.