Fostering research in pediatric interventional radiology: needs assessment and suggestions for support.

BACKGROUND: Due to the rarity of pediatric diseases, collaborative research is the key to maximizing the impact of research studies. A research needs assessment survey was created to support initiatives to foster pediatric interventional radiology research. OBJECTIVE: To assess the status of pediatric interventional radiology research, identify perceived barriers, obtain community input on areas of research/education/support, and create metrics for evaluating changes/responses to programmatic initiatives. MATERIALS AND METHODS: A survey link was sent to approximately 275 members of the Society for Pediatric Interventional Radiology (SPIR) between May and October 2020. Data was collected using a web-based interface. Data collected included practice setting, clinical role, research experience, research barriers, and suggestions for future initiatives. RESULTS: Fifty-nine surveys were analyzed with a staff physician survey response rate of 28% (56/198). A wide range of practice sizes from 15 countries were represented. Respondents were predominantly staff physicians (95%; 56/59) with an average of 11 years (range: 1-25 years) of clinical experience working at academic or freestanding children's hospitals. A total of 100% (59/59) had research experience, and 70% (41/58) had published research with a mean of 30 peer-reviewed publications (range: 1-200). For job security, 56% (33/59) of respondents were expected or required to publish, but only 19% (11/58) had research support staff, and 42% (25/59) had protected research time, but of those, 36% (9/25) got the time "sometimes or never." Lack of support staff, established collaborative processes, and education were identified as top barriers to performing research. CONCLUSIONS: The needs assessment survey demonstrated active research output despite several identified barriers. There is a widespread interest within the pediatric interventional radiology community for collaborative research.

Appendix to the Society of Interventional Radiology Consensus Guidelines for the Periprocedural Management of Thrombotic and Bleeding Risk in Patients Undergoing Percutaneous Image-Guided Interventions: Pediatric Considerations.

PURPOSE: To provide guidance on the use of anticoagulant and antithrombotic agents in pediatric patients undergoing interventional radiology procedures. MATERIALS AND METHODS: A multidisciplinary writing group conducted a comprehensive literature search to identify studies on the topic of interest. Recommendations were developed for procedural risk and medication dosage and withholding. A modified Delphi technique was used to achieve consensus agreement on the recommendations. RESULTS: A total of 24 studies, including systematic reviews and meta-analyses, randomized controlled trials, and prospective and retrospective cohort studies, were identified as relevant. The expert writing group agreed on procedural risk categorization, laboratory testing thresholds, and medication dosage and withholding recommendations specific to pediatric practice. They additionally described the nuances of anticoagulation in clinical conditions specific to pediatrics. CONCLUSIONS: The Society of Interventional Radiology recommends following the guidance provided in the document when developing multidisciplinary management protocols for anticoagulation and antithrombotic treatment in pediatric patients undergoing interventional radiology procedures.

Diagnosis and Follow-up of Incidental Liver Lesions in Children.

ABSTRACT: Incidental liver lesions are identified in children without underlying liver disease or increased risk of hepatic malignancy in childhood. Clinical and imaging evaluation of incidental liver lesions can be complex and may require a multidisciplinary approach. This review aims to summarize the diagnostic process and follow-up of incidental liver lesions based on review of the literature, use of state-of-the-art imaging, and our institutional experience. Age at presentation, gender, alpha fetoprotein levels, tumor size, and imaging characteristics should all be taken into consideration to optimize diagnosis process. Some lesions, such as simple liver cyst, infantile hemangioma, focal nodular hyperplasia (FNH), and focal fatty lesions, have specific imaging characteristics. Recently, contrast-enhanced ultrasound (CEUS) was Food and Drug Administration (FDA)-approved for the evaluation of pediatric liver lesions. CEUS is most specific in lesions smaller than 3 cm and is most useful in the diagnosis of infantile hemangioma, FNH, and focal fatty lesions. The use of hepatobiliary contrast in MRI increases specificity in the diagnosis of FNH. Recently, lesion characteristics in MRI were found to correlate with subtypes of hepatocellular adenomas and associated risk for hemorrhage and malignant transformation. Biopsy should be considered when there are no specific imaging characteristics of a benign lesion. Surveillance with imaging and alpha fetoprotein (AFP) should be performed to confirm the stability of lesions when the diagnosis cannot be determined, and whenever biopsy is not feasible.

Challenges and Opportunities for Continued Success and Growth of Pediatric Interventional Radiology: A Communiqué From the Society for Pediatric Interventional Radiology.

OBJECTIVE: Pediatric interventional radiology (PIR) is a dynamic and growing subspecialty. We will detail our need to evolve like the emerging therapies and innovative imaging options that we provide to children. CONCLUSION: New interventional radiology training pathways, maintaining competency with small volumes of complex procedures, limited availability of pediatric-specific equipment, questions about the safety of sedation in the developing brain, and the dearth of PIR opportunities outside of North America provide challenges and opportunities for the vibrant community of PIR practitioners.

Pediatric Percutaneous Nephrostomy: A Multicenter Experience.

PURPOSE: To analyze technique, outcomes, and complications of a large series of pediatric percutaneous nephrostomy (PCN) procedures performed at 4 tertiary pediatric centers. MATERIALS AND METHODS: Retrospective multicenter study of PCNs performed during an 11-year period. Six hundred seventy-five PCNs were performed on 441 patients (median age: 4 y, range: 1 d-18 y, median weight: 17 kg, range: 0.7-112 kg); 31% were younger than 1 year. The most frequent indications for PCN procedures included hydronephrosis (57%), calculus (14%), and infection (12%). Forty-five percent of patients had severe and 32% had moderate hydronephrosis. RESULTS: Technical success was 99% (n = 668); 7 failures occurred from lost access, during tract dilatation (n = 5) and during staghorn calculi without dilatation (n = 2). General anesthesia was used in 73% of procedures. Combined ultrasound and fluoroscopy was used in 98% of procedures. Of the 668 procedures, 561 (84%) were primary nephrostomy insertions, and 107 (16%) were a variety of exchanges (secondary catheter insertions). Twenty-four of 675 (4%) were transplanted kidneys. Access sites included lower (47%), mid (28%), and upper (12%) poles and pelvis (11%). Catheters were predominantly 7-8 French (n = 352). The mean catheter dwell time was 25 days (0-220 d). Total primary catheter days were 14,482, with an additional 2,241 days after secondary procedures. Follow-up in 653/668 (98%) procedures documented elective removal (79%) and salvage procedures (21%), which included wire exchange (8.7%), nephroureteral stent/catheter conversion (8.8%), and tube upsizing (3.5%). Periprocedural complications occurred in 30/668 (4.5%) procedures: 1 major (0.1%) self-limiting hematuria requiring transfusion and 29 (4.4%) minor complications. CONCLUSIONS: PCN is safe and successful in children of all ages, with few major complications. PCN in children is associated with specific technical challenges and requires ongoing management tailored to the very young to achieve good outcomes.

Diagnosis and management of the venous malformations of Klippel-Trénaunay syndrome.

OBJECTIVE: A dearth of information exists in the literature regarding current practice in the management of Klippel-Trénaunay syndrome (KTS), a rare condition. We review and describe the etiology, diagnosis, and treatment of KTS. METHODS: Relevant data were synthesized from a Medline review using a combination of the keyterms "Klippel" and "Trénaunay." The majority of hits described singular case reports and were subsequently excluded. The remaining papers were then reviewed and included on the basis of the quality of evidence and the authors' discretion. CONCLUSIONS: KTS is characterized by a clinical triad of extremity varicosities, cutaneous vascular malformations, and hypertrophy of soft tissues and long bones. The diagnosis is clinically supplemented with magnetic resonance imaging and computed tomography. Although this syndrome is associated with significant comorbidities, such as pain, edema, ulcerations, and pruritus, it is rarely the cause of death. The backbone of treatment is nonoperative in nature but should be supplemented with minimally invasive, endovascular, and rarely open surgical procedures for refractory cases.

ACR Appropriateness Criteria Radiologic Management of Hepatic Malignancy.

Management of primary and secondary hepatic malignancy is a complex problem. Achieving optimal care for this challenging population often requires the involvement of multiple medical and surgical disciplines. Because of the wide variety of potential therapies, treatment protocols for various malignancies continue to evolve. Consequently, development of appropriate therapeutic algorithms necessitates consideration of medical options, such as systemic chemotherapy; surgical options, such as resection or transplantation; and loco-regional therapies, such as thermal ablation and transarterial embolization techniques. This article provides a review of treatment strategies for the three most common subtypes of hepatic malignancy treated with loco-regional therapies: hepatocellular carcinoma, neuroendocrine metastases, and colorectal metastases. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR appropriateness criteria radiologic management of infected fluid collections.

The best management of infected fluid collections depends on a careful assessment of clinical and anatomic factors as well as an up-to-date review of the published literature, to be able to select from a host of multidisciplinary treatment options. This article reviews conservative, radiologic, endoscopic, and surgical options and their best application to infected fluid collections as determined by the ACR Appropriateness Criteria Expert Panel on Interventional Radiology. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals, and the application, by the panel, of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Quality improvement guidelines for pediatric abscess and fluid drainage.

Image-guided drainage of abscesses and fluid collections is a valuable tool in the treatment of pediatric patients. It may obviate surgery or optimize the child's clinical condition for subsequent surgery. Compared with adults, several differences exist in terms of etiology, risks (especially radiation exposure), preprocedural imaging and planning, technical considerations, support issues such as sedation, and complications. Knowledge of these differences is important in the planning and treatment of these patients. In addition, a quality improvement plan can be used to assess practice performance.

Pediatric arterial interventions.

The spectrum of pediatric vascular pathology differs from the adult population and it varies greatly to include congenital and acquired disorders. Although catheter-directed angiography remains the gold standard, most vascular conditions in the child can be adequately diagnosed with magnetic resonance angiography, computed tomographic angiography, or duplex/Doppler ultrasonography with only a few exceptions, such as intrarenal arterial stenosis, small vessel vasculitides, and visceral vascular malformations. The advancement of catheter and wire technology has made it increasingly possible for complex arterial interventions to be performed in children, including embolization, angioplasty with stent insertion, thrombolysis, and endovascular neurological procedures. More angiographic procedures are being performed with the aim of also being therapeutic. Special considerations in children include the use of appropriate equipment and adequate dosing of contrast and of the various medications used during angiography, particularly in patients less than 15 kg in weight. This article will focus on the management of renovascular hypertension, liver transplant hepatic arterial intervention, and the use of carbon dioxide gas as a contrast agent in the child.

The congenital porto-caval fistula: a unique presentation and novel intervention.

Congenital porto-caval fistulas are uncommon vascular malformations with a varied clinical presentation beginning in infancy and spanning late adulthood. We report a 14-year-old male who presented with dyspnea and cough. His past medical history was significant for a chronic non-immune hemolytic anemia, thrombocytopenia, coagulopathy and a learning disability. He was found to have severe pulmonary hypertension and hyperammonemia associated with a large congenital porto-caval fistula. The abnormal vessel was occluded via endovascular covered stent placement in the vena cava. His pulmonary hypertension has improved remarkably while his chronic anemia, thrombocytopenia and ammonia have normalized to allow improved cognitive performance.

Epstein-Barr-associated leiomyomatosis and T-cell chimerism after haploidentical bone marrow transplantation for severe combined immunodeficiency disease.

BACKGROUND: The clinical course of Epstein-Barr virus (EBV)-associated smooth muscle tumors is variable and there are no reports in patients with mixed T-cell chimerism after bone marrow transplantation (BMT). OBSERVATIONS: A child with X-linked severe combined immunodeficiency disease developed multiple renal and pulmonary leiomyomata 8 years after haploidentical BMT. Epstein-Barr viral DNA was detectable in the blood and in situ hybridization for EBV-encoded RNAs was positive in the tumor. The tumors have been radiographically stable, chimerism remains mixed, and plasma EBV DNA has been repeatedly negative for over 2 years after donor lymphocyte infusion. CONCLUSIONS: EBV-associated smooth muscle tumors may occur in patients who are partially reconstituted after BMT for severe combined immunodeficiency and may not require surgery or chemotherapy.