Research Consensus Panel Follow-Up: A Systematic Review and Update on Cost Research in IR.

PURPOSE: To systematically review cost research in interventional radiology (IR) published since the Society of Interventional Radiology Research Consensus Panel on Cost in December 2016. MATERIALS AND METHODS: A retrospective assessment of cost research in adult and pediatric IR since December 2016 to July 2022 was conducted. All cost methodologies, service lines, and IR modalities were screened. Analyses were reported in a standardized fashion to include service lines, comparators, cost variables, analytical processes, and databases used. RESULTS: There were 62 studies published, with most from the United States (58%). Incremental cost-effectiveness ratio, quality-adjusted life-years, and time-driven activity-based costing (TDABC) analyses were performed in 50%, 48%, and 10%, respectively. The most frequently reported service line was interventional oncology (21%). No studies on venous thromboembolism, biliary, or IR endocrine therapies were found. Cost reporting was heterogeneous owing to varying cost variables, databases, time horizons, and willingness-to-pay (WTP) thresholds. IR therapies were more cost-effective than their non-IR counterparts for treating hepatocellular carcinoma ($55,925 vs $211,286), renal tumors ($12,435 vs $19,399), benign prostatic hyperplasia ($6,464 vs $9,221), uterine fibroids ($3,772 vs $6,318), subarachnoid hemorrhage ($1,923 vs $4,343), and stroke ($551,159 vs $577,181). TDABC identified disposable costs contributing most to total IR costs: thoracic duct embolization (68%), ablation (42%), chemoembolization (30%), radioembolization (80%), and venous malformations (75%). CONCLUSIONS: Although much of the contemporary cost-based research in IR aligned with the recommendations by the Research Consensus Panel, gaps remained in service lines, standardization of methodology, and addressing high disposable costs. Future steps include tailoring WTP thresholds to nation and health systems, cost-effective pricing for disposables, and standardizing cost sourcing methodology.

Introduction to interventional oncology: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

Interventional radiology (IR) is a valuable resource when caring for pediatric solid tumor patients. As minimally invasive, image-guided procedures become more relied upon to answer challenging diagnostic questions and provide alternative therapeutic options, IR is poised to become a contributing member of the multidisciplinary oncology team. Improved imaging techniques allow for better visualization during biopsy procedures, transarterial locoregional treatments have the potential to deliver targeted cytotoxic therapy while limiting systemic side effects, and percutaneous thermal ablation can be used to treat chemo-resistant tumors of various solid organs. Additionally, interventional radiologists are able to perform routine, supportive procedures for oncology patients that include central venous access placement, lumbar punctures, and enteric feeding tube placements with high levels of technical success and excellent safety profiles.

Introduction to interventional radiology's role in palliative care for children with cancer: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

As palliative care continues to be an area of increasing emphasis in pediatric oncology programs, it is important to raise awareness about minimally invasive, image-guided procedures that can supplement more conventional palliative interventions, such as systemic analgesics, external beam radiation, and locoregional anesthesia. These procedures, when performed for appropriately selected patients, can often facilitate discharge from an inpatient facility, and help patients meet their end-of-life goals. This article specifically discusses three palliative procedures performed by interventional radiologists that can assist pediatric palliative care teams in: (a) percutaneous thermal ablation of painful bone metastases, (b) cryoneurolysis, and (c) tunneled drainage catheter placement for malignant pleural effusions and ascites.

Current State of Private Practice and Academic Interventional Radiology: Differences in Practice Structure, Case Mix, and Productivity.

PURPOSE: To investigate whether private practice interventional radiology (IR) groups self-report higher overall productivity given differing case mix and more diagnostic radiology interpretation. MATERIALS AND METHODS: A 60-question survey was distributed to 3,159 self-identified US IR physicians via the Society of Interventional Radiologists member search engine, with 357 responses (11.3% response rate). Of these responses, there were 258 unique practices from 34 US states. RESULTS: Out of 84 IR group responses, private practice IR (PPIR) physicians reported a minimal trend for higher annual work relative value units (wRVUs) per clinical full-time equivalent compared with academic IR physicians (8,000 versus 7,140, P = .202), but this did not reach statistical significance. PPIR groups reported fewer median weekly hours (50 versus 52), more frequent call (every 6 versus every 5 days), and significantly higher median tenured compensation ($573,000 versus $451,000, P = .000). Out of 179 responses, academic practices reported significantly higher case percentages of interventional oncology and complex hepatobiliary intervention (P <.001), and private practices reported significantly higher percentages of musculoskeletal intervention (P < .001) with a nonsignificant trend for stroke or neurologic intervention (P = .010). Private practices reported more wRVUs from the interpretation of diagnostic imaging, at 26% of total wRVU production compared with 7% of total wRVU production for academic practices (P < .001; n = 131). CONCLUSIONS: Self-reported data from private and academic IR groups suggest minimally higher wRVUs per clinical full-time equivalent among PPIRs with lower weekly work hours, more frequent call, differing case mix, and significantly higher tenured compensation among PPIR groups.

How we established a multidisciplinary program for vascular anomalies.

The care of patients with vascular anomalies is quickly becoming a complex field requiring high-quality, coordinated multidisciplinary care. In this article, we review the history of multidisciplinary care in this field, discuss the benefits of this model of care, and outline some of the essential components and structure of a successful vascular anomalies team. We provide an overview of two example programs and a roadmap for other centers to develop their own multidisciplinary vascular anomalies teams.

Coagulopathy and related complications following sclerotherapy of congenital venous malformations.

BACKGROUND: Congenital venous malformations (VMs) are low-flow vascular anomalies that can cause coagulation abnormalities. This phenomenon, referred to as localized intravascular coagulopathy (LIC), is characterized by elevated D-dimer, hypofibrinogenemia, and/or thrombocytopenia. Increased risk for LIC includes patients with an extensive VM, multifocal VM, and Klippel-Trenaunay and CLOVES syndromes. Peri-procedural anticoagulation has been given to prevent complications from LIC in patients undergoing surgical/interventional procedures; however, the rate of clinically relevant complications from sclerotherapy is largely unknown. The purpose of this study is to describe a single-institution's incidence of LIC in patients with VMs and coagulopathy-related complications following sclerotherapy. DESIGN/METHODS: Retrospective chart review of patients, 0-21 years of age, with VM who underwent sclerotherapy without peri-procedural anticoagulation and had coagulation profiles evaluated within 1 month prior to sclerotherapy. DATA COLLECTED: diagnosis type (high vs. low risk for LIC), coagulation profile (including PT/PTT, D-dimer, fibrinogen, and platelet count), sclerosant used, and post-procedure outcomes. Coagulopathy-related complications included clinically relevant bleeding, deep vein thrombosis (DVT), and pulmonary embolism (PE). RESULTS: N = 138 patients; 59.4% were female. The most common location of VM was the lower extremity (47.8%; 66/138). Of patients with high-risk VMs (29/138 [21%]), 11/29 (37.9%) had laboratory values consistent with LIC, whereas 5% (5/109) of low-risk VMs had LIC. In sum, 492 sclerotherapy procedures were performed with no complications of bleeding, DVT, or PE. CONCLUSION: Patients undergoing sclerotherapy for VM with abnormal coagulation profiles may not require peri-procedural low molecular weight heparin (LMWH). Further studies are needed to precisely define which patients would benefit from anticoagulation.

Percutaneous image-guided treatment of aneurysmal bone cysts: is there a superior treatment option?

BACKGROUND: Aneurysmal bone cysts (ABCs) are often treated with intralesional surgery (curettage) with or without adjuvant treatments. Side effects and conflicting results regarding recurrence rates do not suggest one clearly superior therapy. Percutaneous therapeutic options including sclerotherapy and thermal ablation have gained popularity as potential alternatives. OBJECTIVE: The purpose of this retrospective review is to report this institution's experience and results of various image-guided minimally invasive treatments in a single institution series of cases referred to interventional radiology by orthopedic surgery after surgical failure or in patients with anatomically challenging ABCs. MATERIALS AND METHODS: This study identified all patients ≤18 years old who received percutaneous therapy for an ABC, including cryoablation, doxycycline sclerotherapy, microwave ablation or a combination of these modalities. Procedural details, complications, imaging follow-up and clinical follow-up were analyzed. RESULTS: A total of 21 patients received 41 procedures, with major complications seen in 7.7% (3/39) of procedures involving cryoablation or doxycycline sclerotherapy. Patients receiving cryoablation required an average of 1.7 procedures (median: 1 procedure, range: 1-4 procedures) while patients receiving doxycycline sclerotherapy required an average of 3 procedures (median: 2 procedures, range: 1-6 procedures). Patients were followed clinically and with computed tomography or magnetic resonance imaging (average: 23.9 months, range: 3.9-68.3 months). Follow-up imaging demonstrated improvement in 17 (85%) patients. Clinically, 93.8% (15/16) of patients who presented with fracture or pain had markedly reduced or absent pain as well as no fractures. CONCLUSION: Percutaneous image-guided treatment of ABCs demonstrates a favorable efficacy and safety profile. Adding cryoablation may lead to fewer total procedures than using doxycycline sclerotherapy alone.

Percutaneous cryoablation of chondroblastoma and osteoblastoma in pediatric patients.

BACKGROUND: To review the safety and efficacy of percutaneous cryoablation for the treatment of chondroblastoma and osteoblastoma in the pediatric and adolescent population. MATERIALS AND METHODS: A retrospective review from 2016 to 2020 was performed to evaluate clinical and imaging response to percutaneous cryoablation in 11 symptomatic patients with diagnosis of chondroblastoma and osteoblastoma treated from two pediatric hospitals with at least 12-month follow-up. Technical success (correct needle placement and potential full coverage of the tumor with the planned ablation zone) and clinical success (relief of the symptoms) were evaluated. The primary objective was to alleviate pain related to the lesion(s). Immediate and late complications were recorded. Patients were followed in clinic and with imaging studies such as MRI or CT for a minimum of 6 months. RESULTS: A total of 11 patients were included (mean 14 years, age range 9-17; male n = 8). Diagnoses were osteoblastoma (n = 4) and chondroblastoma (n = 7). Locations were proximal humerus (n = 1), femur condyle (n = 1), and proximal femur (n = 1) tibia (n = 3), acetabulum (n = 3), thoracic vertebra (n = 1) and lumbar vertebra (n = 1). Cryoablation was technically successful in all patients. Clinical success (cessation of pain) was achieved in all patients. No signs of recurrence were observed on imaging follow-up in any of the patients. One of the patients developed periprocedural right L2-L3 transient radiculopathy as major immediate complication. CONCLUSIONS: Percutaneous image-guided cryoablation can be considered potentially safe and effective treatment for chondroblastoma and osteoblastoma in children and adolescents.

Vascular anomalies of the head and neck: diagnosis and treatment.

Vascular malformations and vascular tumors comprise the two specific subsets of vascular anomalies that arise as a result of disorganized angiogenesis and neoplasm, respectively. Malformations are separate entities from vascular tumors (e.g., hemangiomas) and are recognized by the International Society for the Study of Vascular Anomalies (ISSVA) as such. Vascular malformations are classified into four main groups: simple, combined, anomalies of major vessels, and those associated with other vascular anomalies. Vascular tumors are neoplastic growths of blood vessels and are morphologically and molecularly distinct from malformations but can arise in the head and neck and have syndromic association. Head and neck vascular anomalies are not uncommon in the pediatric population and require special care in the workup, diagnostic imaging and clinical care. The purpose of this manuscript is to discuss the diagnosis and management of the most common intracranial and extracranial vascular malformations and tumors in the head and neck in children and adolescents.

Natural History of Mixed and Motor Nerve Cryoablation in Humans-A Cohort Analysis.

Eight patients who underwent percutaneous cryoablation of mixed and/or motor nerves over a period of 5 years were identified. Distances from the ablation sites to origins of distal musculature were measured, and times to initial clinical recovery were collected. Strength progression over time following muscle activation was also collected and analyzed. All patients demonstrated activation of all muscles distal to the ablation, and the calculated mean rate of nerve regeneration based on distance to the origin of the assessed musculature and time to muscle activation for the group was 1.5 mm/day ± 1.1.

Percutaneous thermal ablation for treatment of osteoid osteoma: a systematic review and analysis.

OBJECTIVE: Although radiofrequency ablation is well validated for treatment of osteoid osteoma, newer technologies, namely cryoablation, have been less thoroughly studied. The purpose is to perform a systematic review and pooled analysis of percutaneous ablation technologies for treatment of osteoid osteoma with subset analysis of intra-articular and spinal tumors. MATERIAL AND METHODS: A total of 36 of 79 identified manuscripts met inclusion criteria, comprising 1863 ablations in 1798 patients. Inclusion criteria were (1) retrospective or prospective analysis of thermal ablation of osteoid osteomas in any location, (2) at least 6 months of clinical follow-up, (3) 10 or more patients, (4) patients not included in a second study included in this review, and (5) English language or English translation available. Success rate was defined as all ablations minus technical failures, clinical failures, and recurrences. Subset analysis of intra-articular and spinal tumors was performed. RESULTS: Overall success rate was 91.9% (95% CI 91-93%). Technical failure, clinical failure, and recurrence rates were 0.3%, 2.1%, and 5.6% respectively. Complications were seen in 2.5% (95% CI 1.9-3.3%) patients. There was no significant difference when comparing radiofrequency ablation and cryoablation (p = 0.92). Success rates for intra-articular (radiofrequency ablation) and spinal tumors (radiofrequency and cryoablation) were 97% and 91.6% respectively. CONCLUSION: Percutaneous ablation of osteoid osteomas was highly successful with low complication rates. Efficacy of radiofrequency ablation and cryoablation is similar, which is consequential because cryoablation is associated with decreased pain, predictable nerve regeneration, and theoretical immunotherapy benefits. Treatment of more challenging intra-articular and spinal lesions demonstrated similarly high success and low complication rates.

The Role of Generative Adversarial Networks in Radiation Reduction and Artifact Correction in Medical Imaging.

Adversarial networks were developed to complete powerful image-processing tasks on the basis of example images provided to train the networks. These networks are relatively new in the field of deep learning and have proved to have unique strengths that can potentially benefit radiology. Specifically, adversarial networks have the potential to decrease radiation exposure to patients through minimizing repeat imaging due to artifact, decreasing acquisition time, and generating higher quality images from low-dose or no-dose studies. The authors provide an overview of a specific type of adversarial network called a "generalized adversarial network" and review its uses in current medical imaging research.

Congenital Limb Overgrowth Syndromes Associated with Vascular Anomalies.

Congenital limb length discrepancy disorders are frequently associated with a variety of vascular anomalies and have unique genetic and phenotypic features. Many of these syndromes have been linked to sporadic somatic mosaicism involving mutations of the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway, which has an important role in tissue growth and angiogenesis. Radiologists who are aware of congenital limb length discrepancies can make specific diagnoses based on imaging findings. Although genetic confirmation is necessary for a definitive diagnosis, the radiologist serves as a central figure in the identification and treatment of these disorders. The clinical presentations, diagnostic and imaging workups, and treatment options available for patients with Klippel-Trenaunay syndrome, CLOVES (congenital lipomatous overgrowth, vascular anomalies, epidermal nevi, and scoliosis/spinal deformities) syndrome, fibroadipose vascular anomaly, phosphatase and tensin homolog mutation spectrum, Parkes-Weber syndrome, and Proteus syndrome are reviewed. ©RSNA, 2019.

Technical Feasibility and Clinical Effectiveness of Transjugular Intrahepatic Portosystemic Shunt Creation in Pediatric and Adolescent Patients.

PURPOSE: To examine the technical feasibility and clinical efficacy of transjugular intrahepatic portosystemic shunt (TIPS) creation in children and adolescents. MATERIALS AND METHODS: Retrospective review was performed of 59 patients (mean age 12.6 y [range, 1.5-20 y], mean weight 47.5 kg [range, 11.4-112.2 kg], mean Model for End-stage Liver Disease/Pediatric End-stage Liver Disease score 12.5 [range, 6-33]) who underwent 61 TIPS attempts at 3 tertiary children's hospitals from 2001 to 2017 for acute esophageal or gastroesophageal variceal bleeding, primary and secondary prevention of variceal bleeding, and refractory ascites. Pediatric liver disease etiologies included biliary atresia, cystic fibrosis, and ductal plate anomalies. Technical, hemodynamic, and clinical success and patency rates were reported at 1, 6, 12, and 24 months. Statistical analysis evaluated reasons for clinical failure. Kaplan-Meier analysis measured clinical success, patency, and transplant-free survival. RESULTS: Technical success was 93.4% (57/61) in 59 consecutive patients. Most common TIPS indications were treating and preventing esophageal and gastroesophageal variceal bleeding (57/59; 96.6%). Hemodynamic success was 94% (47/50). Clinical success was 80.7% (45/56). Two-year clinical success for acute variceal bleeding and ascites was 94.1% and 100%, respectively. Overall patency at 1, 6, 12, and 24 months was 98.0%, 97.8%, 94.3%, and 91.3%. Two-year transplant-free survival was 88.8%. Overall and major complication rates were 21.2% (13/61) and 8.2% (5/61), with 3 mortalities. Gradient reduction < 12 mm Hg correlated with clinical success (P < .01). CONCLUSIONS: TIPS creation in pediatric patients is technically feasible and clinically efficacious for treatment and prevention of esophageal and gastroesophageal variceal hemorrhage. High 2-year clinical success, patency, and survival rates should encourage providers to consider portosystemic shunts as a bridge to liver transplantation.

Use of percutaneous bleomycin sclerotherapy for orbital lymphatic malformations.

PURPOSE: Bleomycin sclerotherapy has been shown to be a viable treatment for lymphatic malformations. However, its use for these lesions confined to the orbit is becoming increasingly documented in the literature. In this study, we summarize the clinical manifestations and outcomes observed following percutaneous bleomycin sclerotherapy for orbital lymphatic malformation. METHODS: A 5-year retrospective chart review of patients with clinical, radiographic, and/or biopsy-confirmed diagnoses of orbital lymphatic malformation that received bleomycin sclerotherapy was conducted at the Emory Hospital and Clinics. Data examined included patient demographics, patient history and symptoms, clinical findings, radiographic findings, route of bleomycin delivery, and outcome. RESULTS: Of the 10 patients who met inclusion criteria, the median age of treatment was 7 years. The most common presenting symptoms included vision change and proptosis. Nine of 10 patients demonstrated macrocysts (>1 cm) on imaging. Seven of 10 patients had histories of prior interventions including resections, cyst drainage, and debulking. Because 2 of these 10 patients were lost to follow-up, 8 patients remained for post-procedural evaluation. Four of these eight showed improvement of visual acuity after post-bleomycin sclerotherapy. In seven of eight patients, extraocular motility either improved or remained stable. Pretreatment and posttreatment exophthalmometer measurements obtained in four patients revealed an average improvement in proptosis of 65% from their average pretreatment measurements. CONCLUSIONS: Our findings suggest that percutaneous bleomycin sclerotherapy is a viable option for treatment of orbital lymphatic malformations, with potentially greater benefit to those with macrocystic features.

Cone-beam computed tomography guidance with navigational overlay for percutaneous lung nodule biopsy.

BACKGROUND: Cone-beam CT is increasingly used in pediatric interventional radiology procedures. However, the feasibility or safety of using this mode of imaging guidance for percutaneous lung nodule biopsy in children has not been assessed. OBJECTIVE: To retrospectively evaluate safety and diagnostic accuracy of percutaneous lung nodule biopsy in people treated at a pediatric hospital using cone-beam CT with navigational overlay. MATERIALS AND METHODS: Thirty-six consecutive patients from two large tertiary-care children's hospitals with lung nodules of 48 mm or smaller underwent percutaneous lung nodule biopsy using cone-beam CT with navigational overlay. We evaluated patient demographics, pre- and post-biopsy diagnoses, number of biopsy passes, complications, radiation exposure and technical success. RESULTS: Percutaneous lung nodule biopsy was performed for 37 nodules in 36 patients (23 males, 13 females, median age 15.5 years, range 8 months to 23 years). One patient underwent biopsy of two nodules at a single procedure. Median patient weight was 55 kg (range 8-97 kg). Pre-biopsy diagnoses included metastatic sarcoma or other solid tumor (n=11), leukemia/lymphoma (n=13), infection (n=10), chronic granulomatous disease (n=2) and post-transplant lymphoproliferative disorder (PTLD; n=1). Mean number of passes was 5 (range 2-15). Mean pre-procedure international normalized ratio (INR) was 1.1 and platelet count 193 × 109/L. Diagnostic specimens were obtained in 32 of 36 patients (89%). Thirteen complications were encountered in 12 patients (33% of cohort), including 9 pneumothoraces (4 requiring chest tubes); 1 hemothorax, which required a chest tube; and 3 self-limited pulmonary hemorrhages. Mean and median radiation doses were as follows: fluoroscopy time 3 min and 2.4 min, dose-area product (DAP) (recorded in 31 patients) 23,402 Gy·cm2 and 12,453 Gy·cm2, and air kerma 88 mGy and 58 mGy. CONCLUSION: Percutaneous lung nodule needle biopsy can be performed accurately using cone-beam CT with navigational overlay.

Clinical Efficacy of Percutaneous Transhepatic Portal Vein Angioplasty for Late-onset Portal Vein Stenosis in Pediatric Liver Transplant Patients.

BACKGROUND: Stenosis of the portal vein (PV) is a rare complication after liver transplantation (LT) in pediatric patients, and it adversely affects outcomes. We reviewed the safety and efficacy of percutaneous transhepatic balloon angioplasty (PTBA) as a treatment for post-LT late-onset PV stenosis (PVS). METHODS: Three hundred eighteen patients between the ages of 0 and 21 years received an LT from 2001 to 2016 at this tertiary center. Twenty-one children were evaluated for PVS using percutaneous portal venography. RESULTS: Of the 21, 19 patients (7 female, 12 male) with a median age of 12 years (7-15 years) were diagnosed with PVS and received PTBA. Two patients were excluded: one did not have PVS, and one received shunt surgery. Median time between LT and PTBA was 83 months (interquartile range, 49-138). For patients in whom pressure could be accurately measured (n = 9), mean PV pressure gradient was 6.3 mm Hg (SD, 5.0) preprocedure and 0.9 mm Hg (SD, 1.2) postprocedure. Mean percentage improvement in gradient across the stenotic region was 86.2% (SD, 15.9%; P < 0.01). At 12-month postprocedure, there was a mean improvement (pre-PTBA vs post-PTBA means) in bilirubin by 28.2% (0.6 mg/dL vs 0.4 mg/dL, P = 0.07), aspartate aminotransferase by 31.2% (116.3 IU/L vs 28.1 IU/L, P = 0.04), alanine aminotransferase by 40.7% (140.3 IU/L vs 28.6 IU/L, P = 0.07), γ-glutamyltransferase by 29.0% (337.2 IU/L vs 38.0 IU/L, P = 0.06) and platelets by 62.1% (128.3 vs 191.1 × 10/L, P = 0.03). The PV patency was successfully maintained in 18 of 19 patients for a median of 16 months (interquartile range, 5-35). One patient received a successful repeat procedure for restenosis at 6 weeks. CONCLUSION: Angioplasty for PVS after pediatric LT is a safe and effective treatment with good patency and improved clinical outcomes. Longer follow-up studies are required.

Percutaneous Image-Guided Treatment of Benign Musculoskeletal Tumors in Children.

Percutaneous ablation of benign musculoskeletal tumors in children has become an area of significant clinical growth over the last decade. With growing research interest, the technologies available and techniques used are becoming increasingly safe and effective. We review some of the more common ablation technologies and their utility in several common benign bone and soft tissue tumors that occur in children and young adults.