Vertebral Body Bone Ablation with and without a Saline-Infused System in a Porcine Model.

The purpose of this study was to evaluate the effect of bone radiofrequency (RF) ablation in the spine with and without controlled saline infusion. RF ablation with and without controlled saline infusion was performed in the vertebral bodies of 2 swine with real-time temperature and impedance recordings. Histology and magnetic resonance (MR) imaging results were reviewed to evaluate the ablation zone size, breach of spinal canal, and damage to the spinal cord and nerves. There was no difference in maximum and mean temperatures between controlled saline and noninfusion groups. The impedance and power output were not significantly different between the groups. MR imaging and histopathology demonstrated ablation zones confined within the vertebral bodies. Ablation zone size correlated on MR imaging and histopathology by groups. No ablation effect, breach of posterior cortex, spinal cord injury, or nerve or ganglion injury was observed at any level using MR imaging or histology. Controlled saline infusion does not appear to impact bone RF ablation and, specifically, does not increase the ablation zone size.

Cone-Beam CT With Enhanced Needle Guidance and Augmented Fluoroscopy Overlay: Applications in Interventional Radiology.

Digital flat-panel detector cone-beam CT (CBCT), introduced in the early 2000s, was historically used in interventional radiology primarily for liver-directed therapies. However, contemporary advanced imaging applications, including enhanced needle guidance and augmented fluoroscopy overlay, have evolved substantially over the prior decade and now work synergistically with CBCT guidance to overcome limitations encountered with other imaging modalities. CBCT with advanced imaging applications has become increasingly used to facilitate a broad range of minimally invasive procedures, particularly relating to pain and musculoskeletal interventions. Potential advantages of CBCT with advanced imaging applications include greater accuracy for complex needle paths, improved targeting in the presence of metal artifact, enhanced visualization during injection of contrast medium or cement, increased ease when space in the gantry is limited, and reduced radiation doses versus conventional CT guidance. Nonetheless, CBCT guidance remains underutilized, partly relating to lack of familiarity with the technique. This article describes the practical implementation of CBCT with enhanced needle guidance and augmented fluoroscopy overlay and depicts the technique's application for an array of interventional radiology procedures, including epidural steroid injections, celiac plexus block and neurolysis, pudendal block, spine ablation, percutaneous osseous ablation fixation and osteoplasty, biliary recanalization, and transcaval type II endoleak repair.

Comprehensive Palliative Musculoskeletal Interventional Radiology Care for Patients with Cancer.

Substantial advances in percutaneous image-guided minimally invasive musculoskeletal oncologic interventions offer a robust armamentarium for interventional radiologists for management of cancer. The authors outline the most recent advances in such interventions and the role of interventional radiologists in managing cancer in modern-era practice. Percutaneous minimally invasive musculoskeletal interventions including thermal ablation, cementation with or without osseous reinforcement by implants, osteosynthesis, neurolysis, and embolization, as well as palliative injections, have been successfully used by interventional radiologists to achieve durable, timely, safe, effective palliation in a multidisciplinary setting and have been progressively incorporated into the management paradigm for patients with cancer with musculoskeletal involvement. Familiarity with the described interventions and implementation of procedural safety measures, combined with integration of these procedures into clinical practice with the support of the National Comprehensive Cancer Network and the American College of Radiology, as well as continued technologic advances in procedural equipment design, will further enhance the role of interventional radiologists in cancer management. ©RSNA, 2022.

Local Control of Cancers With Various Ablation Techniques.

Metastatic disease to the bone and soft tissue creates significant morbidity because of pain resulting in decreased functional status. Palliative chemotherapy and radiation therapy were historically the mainstays of pain reduction. Minimally invasive technologies such as image-guided ablation and cementoplasty have become common in interventional radiology. Advances in image guidance and ablation technologies have improved the multidisciplinary approach in the management of bone and soft-tissue disease. The minimally invasive nature of the interventions allows prompt initiation or continuation of chemotherapy and radiation therapy. These safe and efficacious procedures have improved patient quality of life by decreasing pain and improving function.

Musculoskeletal Oncologic Interventions: Proceedings from the Society of Interventional Radiology and Society of Interventional Oncology Research Consensus Panel.

Musculoskeletal interventions are increasingly used with palliative and curative intent in the multidisciplinary treatment of oncology patients with bone and soft-tissue tumors. There is an unmet need for high-quality evidence to guide broader application and adoption of minimally invasive interventional technologies to treat these patients. Therefore, the Society of Interventional Radiology Foundation and the Society of Interventional Oncology collaborated to convene a research consensus panel to prioritize a research agenda addressing the gaps in the current evidence. This article summarizes the panel's proceedings and recommendations for future basic science and clinical investigation to chart the course for interventional oncology within the musculoskeletal system. Key questions that emerged addressed the effectiveness of ablation within specific patient populations, the effect of combination of ablation with radiotherapy and/or immunotherapy, and the potential of standardization of techniques, including modeling and monitoring, to improve the consistency and predictability of treatment outcomes.

Vertebroplasty, Kyphoplasty, and Implant-Based Mechanical Vertebral Augmentation.

Vertebral compression fractures are a global public health issue with a quantifiable negative impact on patient morbidity and mortality. The contemporary approach to the treatment of osteoporotic fragility fractures has moved beyond first-line nonsurgical management. An improved understanding of biomechanical forces, consequential morbidity and mortality, and the drive to reduce opioid use has resulted in multidisciplinary treatment algorithms and significant advances in augmentation techniques. This review will inform musculoskeletal radiologists, interventionalists, and minimally invasive spine surgeons on the proper work-up of patients, imaging features differentiating benign and malignant pathologic fractures, high-risk fracture morphologies, and new mechanical augmentation device options, and it describes the appropriate selection of devices, complications, outcomes, and future trends.

Minimally Invasive Stabilization of Periacetabular Metastasis.

Metastatic bone disease to the pelvis can lead to lower quality of life and function secondary to pain. Historically, treatment was palliative with radiation therapy and chemotherapy used to reduce pain. The Harrington procedure and subsequent modifications improved pain and function. In the subset of patients with complications, this would delay potential life-prolonging interventions such as chemotherapy and radiation therapy. Percutaneous palliative pain procedures including ablation and cementoplasty have been developed by interventional radiology for pelvic lesions and have been shown to be safe and efficacious. Additionally, percutaneous methods of pelvic fracture fixation have been developed. Modern image guidance technologies have allowed an expanded multidisciplinary approach to pelvic metastatic disease in a minimally invasive fashion with combinations of ablation, internal fixation, and cementation to improve patient quality of life and outcomes with decreased morbidity and rapid return to radiation and systemic therapies.

Ultrasound-guided diagnostic deep peroneal nerve blocks prior to potential neurectomy: a retrospective review.

OBJECTIVE: To describe our technical and preliminary clinical experience with ultrasound-guided diagnostic deep peroneal nerve (DPN) blocks for patients considering deep peroneal neurectomy. MATERIALS AND METHODS: Retrospective analysis of ultrasound-guided diagnostic DPN blocks performed in the anterior lower leg in patients pursuing deep peroneal neurectomy for foot pain not directly attributable to the DPN. Patient age, sex, foot laterality, diagnosis, nerve block complications, location of the DPN with respect to vascular landmarks in the lower leg, pain relief from nerve block, and pain relief from neurectomy (if performed) were recorded. RESULTS: Twenty-six DPN blocks were performed for 25 feet, of which a majority had pain attributable to midfoot osteoarthritis (22/25). Variable DPN locations with respect to vascular landmarks in the lower leg were observed, including lateral to the anterior tibial artery (12/25), anterior to the artery (5/25), medial to the artery (3/25), lateral to the lateral paired vein (4/25), and 1-cm lateral to the artery (1/25). After DPN blocks, patients reported pain relief in 22/25 feet. Of the eleven patients who proceeded to have a deep peroneal neurectomy, ten reported improved foot pain. CONCLUSION: Diagnostic deep peroneal nerve blocks for patients considering deep peroneal neurectomy for denervation therapy should be performed in the anterior lower leg where the anterior tibial vessels serve as anatomic landmarks. Those who perform DPN blocks with ultrasound guidance should be aware of variable DPN position with respect to the vascular landmarks.

Management of Acute Cholecystitis during Neoadjuvant Therapy in Patients with Pancreatic Adenocarcinoma.

BACKGROUND: Patients with localized pancreatic cancer (PC) can develop acute cholecystitis during neoadjuvant therapy; optimal management remains undefined. METHODS: Consecutive patients with localized PC who had indwelling biliary stents and received neoadjuvant therapy were reviewed. Time from stent placement to the development of acute cholecystitis was calculated. Patients were categorized as having surgical versus nonoperative management of cholecystitis. Time to PC resection was defined as the time from the start of treatment to pancreatic resection. RESULTS: Of the 283 patients with indwelling biliary stents, acute cholecystitis occurred in 17 (6%) patients. The median time from the date of stent placement to the development of cholecystitis was 2.3 months [interquartile range (IQR) 4.6 months]. Acute cholecystitis was managed with cholecystostomy tube placement in 15 (88%) patients and cholecystectomy in 2 (12%). In total, 189 (67%) of the 283 patients completed all intended neoadjuvant therapy and surgery; 10 (59%) of the 17 patients with cholecystitis (10 of 15 managed with a cholecystostomy tube and 0 of 2 managed with cholecystectomy) and 179 (67%) of the 266 patients without cholecystitis (p = 0.47). The median time to PC resection was 3.2 months for the 179 patients without cholecystitis and 3.6 months for the 10 patients with cholecystitis (p = 1.00). CONCLUSIONS: Acute cholecystitis occurred in 6% of patients with indwelling biliary stents during neoadjuvant therapy. Management with a cholecystostomy tube did not delay the completion of neoadjuvant therapy and surgery and should be considered the optimal management of this complication.

Percutaneous cryoablation for the treatment of extra-abdominal desmoid tumors.

BACKGROUND: Desmoid tumors are rare locally invasive, benign neoplasms that develop along aponeurotic structures. Current treatment is complicated by associated morbidity and high recurrence rates. METHODS: A retrospective, single-institution review identified 23 patients (age: 16-77) with extra-abdominal desmoid tumors who received CT-guided percutaneous cryoablation as either a first-line (61%) or salvage (39%) treatment in 30 sessions between 2014 and 2018. Median maximal lesion diameter was 69 mm (range: 11-209). Intent was curative in 52% and palliative in 48%. Contrast-enhanced cross-sectional imaging was obtained before and after treatment in addition to routine clinical follow-up. RESULTS: Technical success was achieved in all patients. The median follow-up was 15.4 months (3.5-43.4). Symptomatic improvement was demonstrated in 89% of patients. At 12 months, the average change in viable volume was -80% (range -100% to + 10%) and response by modified response evaluation criteria in solid tumors (mRECIST) was CR 36%, PR 36%, and SD 28% No rapid postablation growth or track seeding was observed. Four patients underwent repeat cryoablation for either residual or recurrent disease. Two patients sustained a major procedural complication consisting of significant neuropraxia. CONCLUSION: Cryoablation for desmoid tumors demonstrates a high degree of symptom improvement and local tumor control on early follow-up imaging with relatively low morbidity.

The Role of Ablation in Cancer Pain Relief.

PURPOSE OF REVIEW: The purpose of this article is to describe the concepts of ablation techniques for pain relief in symptomatic oncologic patients. Controversies concerning techniques and products will be addressed. RECENT FINDINGS: Despite conventional pain palliative techniques, cancer patients often endorse unresolved somatic and neuropathic pain that can present as a great burden to quality of life. In non-operative patients, several techniques have been applied to minimize opioid dependence. While radiotherapy is often considered as a non-invasive option, percutaneous ablation has been advanced as a minimally-invasive alternative with clear procedural and outcome advantages. Similar to radiation therapy, percutaneous ablation techniques can act either upon nerve structures responsible for pain mediation signals (neurolysis) or directly upon the tumor to relieve tumor-mediated inflammation and decompress tumor compression of adjacent structures. Percutaneous ablation provides valuable neurolysis and tumor-directed pain palliative effects to be incorporated into clinical guidelines for pain reduction in oncologic patients. Selection among different ablation techniques should be based upon an individually tailored approach, to include consideration of all treatment modalities.

A Cross-Sectional Survey of Interventional Radiologists and Vascular Surgeons Regarding the Cost and Reimbursement of Common Devices and Procedures.

PURPOSE: To evaluate knowledge of interventional radiologists (IRs) and vascular surgeons (VSs) on the cost of common devices and procedures and to determine factors associated with differences in understanding. MATERIALS AND METHODS: An online survey was administered to US faculty IRs and VSs. Demographic information and physicians' opinions on hospital costs were elicited. Respondents were asked to estimate the average price of 15 commonly used devices and to estimate the work relative value units (wRVUs) and average Medicare reimbursements for 10 procedures. Answer estimates were deemed correct if values were ± 25% of the actual costs. Multivariate logistical regression was used to calculate odds ratios and 95% confidence intervals. RESULTS: Of the 4,926 participants contacted, 1,090 (22.1%) completed the questionnaire. Overall, 19.8%, 22.8%, and 31.9% were accurate in price estimations of devices, Medicare reimbursement, and wRVUs for procedures. Physicians who thought themselves adequately educated about wRVUs were more accurate in predicting procedural costs in wRVUs than physicians who responded otherwise (odds ratio = 1.40, 95% confidence interval, 1.29-1.52; P < .0001). Estimation accuracies for procedures showed a positive trend in more experienced physicians (≥ 16 y), private practice physicians, and physicians who practice in rural areas. CONCLUSIONS: This study suggests that IRs and VSs have limited knowledge regarding device costs. Given the current health care environment, more attention should be placed on cost education and awareness so that physicians can provide the most cost-effective care.

Safety and Efficacy of Minimally Invasive Acetabular Stabilization for Periacetabular Metastatic Disease with Thermal Ablation and Augmented Screw Fixation.

PURPOSE: To evaluate minimally invasive acetabular stabilization (MIAS) with thermal ablation and augmented screw fixation for impending or minimally displaced fractures of the acetabulum secondary to metastatic disease. MATERIALS AND METHODS: Between February 2011 and July 2014, 13 consecutive patients underwent thermal ablation, percutaneous screw fixation, and polymethyl methacrylate augmentation for impending or nondisplaced fractures of the acetabulum secondary to metastatic disease. Functional outcomes were evaluated before and after the procedure using the Musculoskeletal Tumor Society (MSTS) scoring system. Complications, hospital length of stay, and eligibility for chemotherapy and radiation therapy were assessed. RESULTS: All procedures were technically successful with no major periprocedural complications. The mean total MSTS score improved from 23% ± 11 before MIAS to 51% ± 21 after MIAS (P < .05). The mean MSTS pain scores improved from 0% (all) to 32% ± 22 after MIAS (P < .05). The mean MSTS walking ability score improved from 22% ± 19 to 55% ± 26 after MIAS (P < .05). Two complications occurred; a patient had a minimally displaced fracture of the superior pubic ramus at the site of repair but remained ambulatory, and septic arthritis was diagnosed in another patient 12 months after repair. The average length of hospital stay was 2 days ± 3.6; six patients were discharged within 24 hours of the procedure. All patients were eligible for chemotherapy and radiation therapy immediately after the procedure. CONCLUSIONS: MIAS is feasible, improves pain and mobility, and offers a minimally invasive alternative to open surgical reconstruction.

Safeguards to prevent neurologic complications after epidural steroid injections: consensus opinions from a multidisciplinary working group and national organizations.

BACKGROUND: Epidural corticosteroid injections are a common treatment for radicular pain caused by intervertebral disc herniations, spinal stenosis, and other disorders. Although rare, catastrophic neurologic injuries, including stroke and spinal cord injury, have occurred with these injections. METHODS: A collaboration was undertaken between the U.S. Food and Drug Administration Safe Use Initiative, an expert multidisciplinary working group, and 13 specialty stakeholder societies. The goal of this collaboration was to review the existing evidence regarding neurologic complications associated with epidural corticosteroid injections and produce consensus procedural clinical considerations aimed at enhancing the safety of these injections. U.S. Food and Drug Administration Safe Use Initiative representatives helped convene and facilitate meetings without actively participating in the deliberations or decision-making process. RESULTS: Seventeen clinical considerations aimed at improving safety were produced by the stakeholder societies. Specific clinical considerations for performing transforaminal and interlaminar injections, including the use of nonparticulate steroid, anatomic considerations, and use of radiographic guidance are given along with the existing scientific evidence for each clinical consideration. CONCLUSION: Adherence to specific recommended practices when performing epidural corticosteroid injections should lead to a reduction in the incidence of neurologic injuries.

A single-center experience in capturing inpatient evaluation and management for an IR practice.

PURPOSE: To demonstrate that interventional radiologists can capture work relative value units (wRVUs) for the work that is already being performed providing evaluation and management (E&M) clinical services. MATERIALS AND METHODS: A team approach was implemented to optimize revenue capture for inpatient E&M. Structured templates were created for inpatient documentation to ensure that maximum wRVUs were captured. Inpatient billing was audited from fiscal year 2011 (1 year before meeting and structured template creation) through fiscal year 2014. Specifically, data were collected on total charges, collections, wRVUs and total number of inpatient E&M encounters, and the level of the billed encounter. RESULTS: Retrospective annual audits revealed that overall inpatient E&M billing charges increased by 722%, whereas collections increased by 831% from 2011 to 2014. The wRVUs increased in 2011 from 181.74 to 1,396.9 (669% increase) in 2014, and the number of inpatient E&M encounters billed increased from 130 to 693 (433% increase) over that same time period. Lower level billing (level I) declined from 30% to 19%, and complex billing levels (level II or higher) increased from 70% to 81%. CONCLUSIONS: By implementing a systems approach to revenue management, which includes physician and billing staff meetings and the use of structured templates, billing capture from inpatient E&M services can be improved.

Safety and efficacy of transarterial chemoembolization in patients with transjugular intrahepatic portosystemic shunts.

BACKGROUND: Transarterial chemoembolization (TACE) for the treatment of hepatocellular carcinoma (HCC) is an important option as the majority of patients present with advanced disease. Data regarding treatment outcomes in patients who have undergone transjugular intrahepatic portosystemic shunts (TIPS) are limited. The present study seeks to evaluate the safety and efficacy of TACE in HCC patients with a TIPS. METHODS: A retrospective review identifying patients with HCC and concomitant TIPS who were treated with TACE was performed. RESULTS: From 1999 to 2014, 16 patients with HCC underwent a total of 27 TACE procedures; eight patients required multiple treatments. The median patient age at the time of the initial TACE was 60.5 years [interquartile range (IQR) : 52.5-67.5] with the majority being male (n = 12, 75%) and Childs-Pugh Class B (n = 12, 75%). At 6 weeks after TACE, 56.3% of patients achieved an objective response rate (complete and partial response) by mRECIST criteria. Clavien Grade 3 or higher complications occurred in 11.1% of TACE procedures. There were no peri-procedural deaths. The median progression-free (PFS) and overall survival (OS) were 9 and 22 months, respectively, when censored for liver transplantation (median follow-up: 11.5 months). CONCLUSION: TACE is an effective treatment strategy for HCC in TIPS patients; albeit may be associated with higher complication rates.

Percutaneous in utero thoracoamniotic shunt creation for fetal thoracic abnormalities leading to nonimmune hydrops.

PURPOSE: To describe a transabdominal, transuterine Seldinger-based percutaneous approach to create a shunt for treatment of fetal thoracic abnormalities. MATERIALS AND METHODS: Five fetuses presented with nonimmune fetal hydrops secondary to fetal thoracic abnormalities causing severe mass effect. Under direct ultrasound guidance, an 18-gauge needle was used to access the malformation. Through a peel-away sheath, a customized pediatric transplant 4.5-F double J ureteral stent was advanced; the leading loop was placed in the fetal thorax, and the trailing end was left outside the fetal thorax within the amniotic cavity. RESULTS: Seven thoracoamniotic shunts were successfully placed in five fetuses; one shunt was immediately replaced because of displacement during the procedure, and another shunt was not functioning at follow-up requiring insertion of a second shunt. All fetuses had successful decompression of the thoracic malformation, allowing lung reexpansion and resolution of hydrops. Three of five mothers had meaningful (> 7 d) prolongation of their pregnancies. All pregnancies were maintained to > 30 weeks (range, 30 weeks 1 d-37 weeks 2 d). There were no maternal complications. CONCLUSIONS: A Seldinger-based percutaneous approach to draining fetal thoracic abnormalities is feasible and can allow for prolongation of pregnancy and antenatal lung development and ultimately result in fetal survival.

Percutaneous bone lesion ablation.

Benign tumors and metastatic bone lesions can be treated by ablation techniques performed either alone or in combination with other percutaneous techniques. Ablation techniques include ethanol or acetic acid injection and thermal ablation by means of energy deposition [including laser, radiofrequency, microwave, cryoablation, radiofrequency ionization and magnetic resonance (MR)-guided high-intensity focused ultrasound (HIFU)]. Goal definition of the therapy is crucial: ablation techniques can be proposed as curative treatments in benign bone tumors or oligometastatic disease (<3 lesions). Alternatively, these techniques can be proposed as palliative treatments aiming at reduction of pain, local control of the disease and tumor decompression. Depending on the lesion's location ablation can be combined with cementation with or without further metallic augmentation; local tumor control can be enhanced by combining ablation with transarterial bland embolization or chemoembolization. Thermal ablation of bone and soft tissues is characterized by high success and relatively low rates of potential complications, mainly iatrogenic thermal damage of surrounding sensitive structures. Successful thermal ablation requires a sufficient ablation volume and thermal protection of the surrounding vulnerable structures. This article will describe the general principles governing ablation and the mechanism of action for each technique and in addition will review the literature about safety and effectiveness of percutaneous imaging-guided ablation for benign and malignant (primary and metastatic) lesions.

Recurrence after microwave ablation of liver malignancies: a single institution experience.

BACKGROUND: Microwave ablation (MWA) is increasingly used to achieve local control for liver tumours. This study sought to examine a monocentric experience with MWA, with a primary hypothesis that primary tumour histology was a significant predictor of early recurrence. METHODS: Retrospective single-institution review identified consecutive patients with liver tumours treated by MWA. Cox proportional hazards models assessed significance of prognostic variables. RESULTS: Seventy-two patients (43 female, 60%) underwent 83 MWA procedures for 157 tumours. Tumour histologies included hepatocellular cancer (10 operations), colorectal metastases (39), metastatic carcinoid (20) and other (14). The median tumour size was 2.0 cm. A concomitant liver resection was performed in 50 cases (60%). Crude peri-operative morbidity and mortality rates were 16% and 1%, respectively. The median follow-up was 16 months. Ablations were complete for 149 out of 157 tumours (95%). The median overall and recurrence-free survivals were 36 and 18 months, respectively. There was no difference in time to recurrence between the primary tumour types. In multivariable models, recurrence-free survival was independently associated with the use of neoadjuvant [hazard ratio (HR): 2.90, 95% confidence interval (CI): 1.09-7.76, P = 0.034] and adjuvant chemotherapy (HR: 0.36, 95% CI: 0.15-0.82, P = 0.016). CONCLUSIONS: MWA is a safe and feasible approach for local control of liver tumours. While chemotherapy administration was associated with time to recurrence after MWA, larger studies are needed to corroborate these findings.