Percutaneous biopsy for the diagnosis, risk stratification, and molecular profiling of neuroblastoma: A single-center retrospective study.

PURPOSE: To determine whether percutaneous core needle biopsy (PCNB) is adequate for the diagnosis and full molecular characterization of newly diagnosed neuroblastoma. MATERIALS AND METHODS: Patients with newly diagnosed neuroblastoma who underwent PCNB in interventional radiology at a single center over a 5-year period were included. Pre-procedure imaging and procedure details were reviewed. Rates of diagnostic success and sufficiency for International Neuroblastoma Pathology Classification (INPC), risk stratification, and evaluation of genomic markers utilized in the Children's Oncology Group risk stratification, and status of the anaplastic lymphoma kinase (ALK) gene were assessed. RESULTS: Thirty-five patients (13 females, median age 2.4 years [interquartile range, IQR: 0.9-4.4] and median weight 12.4 kg [IQR: 9.6-18]) were included. Most had International Neuroblastoma Risk Group Stage M disease (n = 22, 63%). Median longest axis of tumor target was 8.8 cm [IQR: 6.1-12]. A 16-gauge biopsy instrument was most often used (n = 20, 57%), with a median of 20 cores [IQR: 13-23] obtained. Twenty-five specimens were assessed for adequacy, and 14 procedures utilized contrast-enhanced ultrasound guidance. There were two post-procedure bleeds (5.7%). Thirty-four of 35 procedures (97%) were sufficient for histopathologic diagnosis and risk stratification, 94% (n = 32) were sufficient for INPC, and 85% (n = 29) were sufficient for complete molecular characterization, including ALK testing. Biologic information was otherwise obtained from bone marrow (4/34, 12%) or surgery (1/34, 2.9%). The number of cores did not differ between patients with sufficient versus insufficient biopsies. CONCLUSION: In this study, obtaining multiple cores with PCNB resulted in a high rate of diagnosis and successful molecular profiling for neuroblastoma.

Embolization for pediatric trauma.

BACKGROUND: The management of pediatric trauma with trans-arterial embolization is uncommon, even in level 1 trauma centers; hence, there is a dearth of literature on this subject compared to the adult experience. OBJECTIVE: To describe a single-center, level 1 trauma center experience with arterial embolization for pediatric trauma. MATERIALS AND METHODS: A retrospective review was performed to identify demographics, transfusion requirements, pre-procedure imaging, procedural details, adverse events, and arterial embolization outcomes over a 19-year period. Twenty children (age 4.5 months to 17 years, median 13.5 years; weight 3.6 to 108 kg, median 53 kg) were included. Technical success was defined as angiographic resolution of the bleeding-related abnormality on post-embolization angiography or successful empiric embolization in the absence of an angiographic finding. Clinical success was defined as not requiring additional intervention after embolization. RESULTS: Seventy-five percent (n=15/20) of patients required red blood cell transfusions prior to embolization with a mean volume replacement 64 ml/kg (range 12-166 ml/kg) and the median time from injury to intervention was 3 days (range 0-16 days). Technical success was achieved in 100% (20/20) of children while clinical success was achieved in 80% (n=16/20). For the 4 children (20%) with continued bleeding following initial embolization, 2 underwent repeat embolization, 1 underwent surgery, and 1 underwent repeat embolization and surgery. Mortality prior to discharge was 15% (n=3). A post-embolization mild adverse event included one groin hematoma, while a severe adverse event included one common iliac artery pseudoaneurysm requiring open surgical ligation. CONCLUSIONS: In this single-center experience, arterial embolization for hemorrhage control in children after trauma is feasible but can be challenging and the clinical failure rate of 20% in this series reflects this complexity. Standardization of pre-embolization trauma assessment parameters and embolic techniques may improve outcomes.

Endovascular closure of a congenital extrahepatic portosystemic shunt for the treatment of hepatopulmonary syndrome in an infant.

Congenital portosystemic shunts may result in the development of hepatopulmonary syndrome, typically presenting with progressive hypoxemia in later childhood. We describe a case of a 5-month-old male with heterotaxy with polysplenia presenting with new onset hypoxemia. Subsequent evaluation identified an extrahepatic portosystemic shunt arising from the confluence of the main portal and superior mesenteric veins draining into the left renal vein. To treat his hypoxemia and prevent future complications of shunting, the patient underwent a successful single-stage endovascular closure.

Middle meningeal artery embolization in the management of chronic subdural hematoma in medically complex pediatric neurosurgical patients: technical note.

Middle meningeal artery (MMA) embolization has gained acceptance as a treatment for chronic subdural hematoma (cSDH) in adult patients but has not been well described in pediatric patients. Standard cSDH treatment has historically consisted of burr hole drainage with or without subdural drain placement. However, due to the high rate of recurrence and frequency of comorbidities within this population, as both pediatric and adult patients with cSDH frequently have concurrent cardiac disease and a need for anticoagulant therapies, MMA embolization has increasingly demonstrated its value as both an adjunctive and primary treatment. In this report, the authors present 3 cases of successful MMA embolization in medically complex children at a single institution. MMA embolization was used as a primary treatment modality and as an adjunctive therapy in the acute setting following surgical hematoma evacuation. Two patients were receiving anticoagulation treatment requiring reversal. Technical considerations specific to the pediatric population as well as those common to both the pediatric and adult populations are addressed. Further work is needed to define the optimal indications and outcomes for MMA embolization in children with cSDH.

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.

Percutaneous Nephrostomy in Neonates and Young Infants.

PURPOSE: To describe a single-center experience of placing percutaneous nephrostomy (PCN) tubes in neonates and young infants aged ≤3 months. MATERIALS AND METHODS: This retrospective study evaluated PCN placement during a 19-year period. Medical records were reviewed for patient demographics, indications, procedure details, catheter-related adverse events, and outcomes. A total of 45 primary PCN insertions were attempted in 29 children (median age, 11 days [range, first day of life to 3 months]; median weight, 3.5 kg [range, 1.4-7.0 kg]). Salvage procedures resulted in 13 secondary catheters in 6 children. The most common indication was ureteropelvic junction obstruction (40.0%), and the most common urinary tract dilation classification was P3 (88.9%). RESULTS: Technical success for primary placements was 95.6%; both technical failures were due to loss of access in the same patient. Of primary placements, 76.7% were electively removed, 6.9% were dislodged but not replaced, and the remaining 16.3% required salvage procedures. Mechanical adverse events occurred in 20.9% of primary and 53.8% of secondary catheters, including partial retraction, complete dislodgement, and occlusion. Urinary tract infections (UTIs) occurred in 18.6% of primary and 15.4% of secondary catheters. Urosepsis occurred in 2.3% of primary and 7.7% of secondary catheters. Median primary catheter dwell time was 41 days (range, 1-182 days) and median secondary catheter dwell time was 31 days (range, 10-107 days). CONCLUSION: PCN placement in neonates and young infants has a high technical success rate, although not without particular procedural and management challenges of catheter malfunction and UTI.

Genomic profiling informs diagnoses and treatment in vascular anomalies.

Vascular anomalies are malformations or tumors of the blood or lymphatic vasculature and can be life-threatening. Although molecularly targeted therapies can be life-saving, identification of the molecular etiology is often impeded by lack of accessibility to affected tissue samples, mosaicism or insufficient sequencing depth. In a cohort of 356 participants with vascular anomalies, including 104 with primary complex lymphatic anomalies (pCLAs), DNA from CD31+ cells isolated from lymphatic fluid or cell-free DNA from lymphatic fluid or plasma underwent ultra-deep sequencing thereby uncovering pathogenic somatic variants down to a variant allele fraction of 0.15%. A molecular diagnosis, including previously undescribed genetic causes, was obtained in 41% of participants with pCLAs and 72% of participants with other vascular malformations, leading to a new medical therapy for 63% (43/69) of participants and resulting in improvement in 63% (35/55) of participants on therapy. Taken together, these data support the development of liquid biopsy-based diagnostic techniques to identify previously undescribed genotype-phenotype associations and guide medical therapy in individuals with vascular anomalies.

Novel method to biopsy aneurysmal bone cysts in children.

PURPOSE: The thin and friable septations composing aneurysmal bone cysts (ABC) may be challenging to target for percutaneous biopsy. The purpose of this study was to describe and evaluate a novel method of ABC biopsy using endomyocardial biopsy forceps as an attempt to capture larger fragments of tissue for diagnosis. METHODS AND MATERIALS: This was a retrospective study performed over a 17-year period. Patients <18 years old who underwent percutaneous biopsy for a presumed ABC, based on pre-procedure imaging, were included. Medical records were reviewed to identify age, sex, lesion location, biopsy procedure details, complications, and pathology results. A diagnostic biopsy was defined as conclusive histologic confirmation. Inconclusive findings or findings suggestive of but not diagnostic of an ABC were treated as non-diagnostic, even if imaging and clinical findings were characteristic. Biopsy device selection and quantity of tissue obtained was at the discretion of the pediatric interventional radiologist. Fisher's exact test was used to compare the diagnostic yield of standard biopsies to those employing biopsy forceps. RESULTS: Twenty-three biopsies were performed in 18 patients (11 female) with a median age of 14.7 years (IQR 10.6-15.6). Lesions were located in the extremities (7, 30.4%), chest (6, 26.1%), pelvis (5, 21.7%), spine (4, 17.4%), and mandible (1, 4.3%). Specimens were obtained using a 13- or 15-gauge bone coring needle (11, 47.8%); 14-, 16-, or 18-gauge soft tissue needle (6, 26.1%); or a combination of bone and soft tissue (4, 17.4%) needles. Endomyocardial biopsy forceps were utilized in 7 cases (30.4%), 2 in which it was the only device used. Overall, a conclusive pathologic diagnosis was made in 13/23 (56.5%) biopsies. Of the diagnostic biopsies, 1 was a unicameral bone cyst and all others were ABCs. No malignancy was identified. Compared to the standard approach, the use of forceps was more likely to result in a diagnostic biopsy (40.0% vs 100.0%, p = 0.008). There were no complications. CONCLUSIONS: Endomyocardial biopsy forceps offer an additional, novel technique to biopsy presumed ABCs and may improve diagnostic yield.

Central venous access in children: Placement trends over the last decade.

PURPOSE: To evaluate central venous access placement trends for radiology and non-radiology services over the last decade. MATERIALS AND METHODS: Children who had central venous access procedures included in a large administrative database of 49 pediatric institutions in the United States between 2010 and 2020 were included. Patient demographics and patient specific factors were compared between groups. The percentage of procedures performed by interventional radiology (IR) and non-radiology services were compared over time and by region. RESULTS: A total of 483,181 vascular access encounters were recorded (45.3% female; median age 2 years (IQR 0-11 years)). Approximately one quarter of vascular access encounters were IR-led, with a slight increase of 3.8% between 2010 and 2020. Children who underwent IR-placed vascular access were older (median age of 4 years compared to 1 year in non-radiology encounters). Interventional radiology-placed access was greatest in the Midwest (33.5%) with a decrease of 5.9% over the study period; in the other three regions, IR-performed encounters increased. Patient comorbidities more prevalent in the IR encounters were technology dependence (42.4% of all radiology encounters), gastrointestinal (34.9%), respiratory (20.8%), and transplant (8.1%), while those which were more prevalent in the non-radiology encounters were nephrology/urology (21.4% of all non-radiology encounters), prematurity/neonatal (17.3%), and malignancy (17.3%). CONCLUSIONS: Interventional radiology-provided vascular access services have slightly increased over the last decade without significant service-line transfer to other specialties. Underlying comorbidities in IR-led vascular access encounters vary across institutions based on referral patterns, possibly reflecting the adoption of ultrasound guidance by other pediatric subspecialties.

Length of Bowel Rest Does Not Predict Gastrojejunostomy Tube-Associated Intussusception Recurrence.

OBJECTIVES: One potential treatment for gastrojejunostomy (GJ) tube-related intussusception is bowel rest, whereby the GJ tube is replaced with a gastrostomy tube. The aim of this study was to determine whether bowel rest length was associated with decreased risk of re-intussusception. METHODS: Pediatric patients with GJ tube-related intussusceptions were identified during the study period of January 1, 2010 and August 1, 2021. Records were reviewed for demographics, symptoms, need for central access to initiate parenteral nutrition, and length of stay. Comparison was made between patients with intussusception recurrence within 30 days and those without. Those undergoing earlier replacement, defined as the first quartile of rest time, or 72 hours, were then compared to longer periods of bowel rest. RESULTS: Forty-six intussusceptions were included, with a median age of 2.8 years (interquartile range, IQR: 1.4-4.1) and weight of 12 kg (IQR: 8.9-15.4). All patients diagnosed as outpatient (54.3%) required hospital admission and 9 of 46 (19.6%) required central access. There were 7 recurrences (15.2%). There was no difference in recurrence based on time of bowel rest (5 days in those without vs 6 days in those with, P = 0.30) nor a difference in recurrence with <72 hours of bowel rest compared to >72 hours (1/15, 6.7% vs 6/31, 19.3%). Patients undergoing earlier exchange had a shorter median length of hospital stay (3 vs 8.5 days, P = 0.003). CONCLUSION: Length of bowel rest was not associated with recurrent GJ tube-related intussusceptions. If bowel rest is utilized, <72 hours may be sufficient to decrease length of hospital stay.

Large scalp venous malformation in a pediatric patient managed with sclerotherapy and surgery: a case report and review of literature.

BACKGROUND: Venous malformations (VMs) are slow-flow vascular anomalies present at birth that enlarge during adolescence, subsequently causing thrombosis, hemorrhage, and pain. CASE PRESENTATION: We describe a case of an adolescent male presenting with a large scalp venous malformation. Given the size and location of the lesion, a hybrid approach employing both sclerotherapy and surgical resection was utilized. The VM was successfully removed without complication. CONCLUSION: A hybrid approach is a safe and effective treatment consideration for immediate management of large venous malformation in higher-risk locations.

Adjunctive techniques for percutaneous enteral access in children: a pictorial review.

Primary percutaneous gastrostomy and gastrojejunostomy tube placements are fundamental procedures performed in pediatric interventional radiology, with both antegrade and retrograde techniques described. In pediatric patients, however, challenges may arise due to smaller patient size and anatomical variations. Several adjunctive techniques may facilitate safe percutaneous access in the setting of a limited percutaneous gastric access window. These include the intra-procedural use of cone beam computed tomography (CT), percutaneous needle decompression in the setting of distended air-filled bowel interposed between the stomach and abdominal wall, post-pyloric balloon occlusion to facilitate gastric distension, ultrasound-guided gastric puncture, and intra-gastric contrast-enhanced ultrasound (ceUS) to define the relationship of the gastric wall and the anterior abdominal wall. Adjunctive techniques may increase successful primary percutaneous gastroenteric tube placement and may improve operator confidence in safe placement.

Indeterminate Thyroid Fine-Needle Aspirations in Pediatrics: Exploring Clinicopathologic Features and Utility of Molecular Profiling.

INTRODUCTION: The diagnostic utility of molecular profiling for the evaluation of indeterminate pediatric thyroid nodules is unclear. We aimed to assess pediatric cases with indeterminate thyroid fine-needle aspiration (FNA) alongside clinicopathologic features and mutational analysis. METHODS: A retrospective review of 126 patients with indeterminate cytology who underwent FNA between January 2010 and December 2021 at the Children's Hospital of Philadelphia was performed. Indeterminate cases defined by The Bethesda System for Reporting Thyroid Cytopathology (AUS/FLUS or TBSRTC III; FN/SFN or TBSRTC IV; SM or TBSRTC V) were correlated to clinicopathologic and genetic characteristics. RESULTS: Of the 114 surgical cases, 48% were malignant, with the majority of malignant cases diagnosed as follicular variant of papillary thyroid carcinoma (28/55). Risk of malignancy increased with TBSRTC category: 23% for AUS/FLUS, 51% for FN/SFN, and 100% for SM nodules. There were significant differences in surgical approach (p < 0.01), performance of lymph node dissection (p < 0.01), histological diagnosis (p < 0.01), primary tumor focality/laterality (p = 0.04), and lymphatic invasion (p = 0.02) based on TBSRTC classification, with resultant differences in post-surgical risk stratification per American Thyroid Association (ATA) Pediatric Guidelines (p = 0.01). Approximately 89% (49/55) of cases were classified as ATA low risk, and 5 of 6 patients with ATA intermediate- or high-risk disease had SM cytology. Somatic molecular testing was performed in 40% (51/126) of tumors; 77% (27/35) of malignant cases and 38% (6/16) of benign cases harbored driver alteration(s). Of the driver-positive malignant cases, 52% (14/27) were associated with low risk (DICER1, PTEN, RAS, and TSHR mutations), 33% (9/27) were associated with high risk (BRAF mutations and ALK, NTRK, and RET fusions), and 15% (4/27) had unreported risk for invasive disease (APC, BLM, and PPM1D mutations and TG-FGFR1 fusion). Incidence of high-risk drivers increased with TBSRTC category. Approximately 23% (8/35) of patients harboring thyroid malignancy did not have an identifiable driver alteration. CONCLUSIONS: Molecular analysis is useful to discriminate benign and malignant thyroid nodules with indeterminate cytology. Patients with driver genetic alteration(s) and indeterminate cytology should consider surgical management secondary to the high incidence (82%; 27/33) of thyroid malignancy in these patients.

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.

Pediatric trauma and the role of the interventional radiologist.

PURPOSE: While interventional radiologists occupy a critical role in adult trauma management, the role of interventionalist in pediatric trauma continues to evolve. The indications for transarterial embolization (TAE) are significantly different in pediatric patients in whom non-operative management (NOM) has a much more prominent role than in adults. Contrast extravasation on imaging may not require acute surgical or interventional management as it would in an adult. There are also areas in which pediatric interventional radiology is increasingly useful such as pelvic TAE in failed management, or splenic embolization to treat bleeding without the loss of splenic function inherent to surgical splenectomy. The rapid evolution of techniques and devices in pediatric patients is also changing what interventions are possible in pediatric trauma management which necessitates frequent reassessment of the guidelines and interventional radiology's role in caring for these patients. CONCLUSION: This review seeks to consolidate the recent literature to describe the evolving role of the interventional radiologist in pediatric trauma management.

Bowel perforation following percutaneous sclerotherapy of an intra-abdominal lymphatic malformation.

Mesenteric lymphatic malformations result from abnormal proliferation of disorganized mesenteric lymphatic channels. Sclerotherapy is often preferred over surgery as it is less invasive and has lower post-procedure morbidity. Sclerotherapy has been described as durable and effective with a low complication rate. We describe a serious complication from sclerotherapy of a lymphatic malformation extending from the mesentery through the bowel wall, highlighting the spectrum of this pathology and the need for multidisciplinary management of complex cases.