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Background: Portomesenteric and portosystemic venous occlusive disease may lead to portomesenteric hypertension, variceal bleeding, ascites and hypersplenism. Data regarding endovascular reconstructive strategies in children, however, are limited., Objective: To report technical success, outcome and patency of portomesenteric and portosystemic venous reconstruction using VIABAHN VBX balloon-expandable endoprostheses in pediatric patients., Materials and Methods: Five pediatric patients (median age: 15 years, range: 4-18 years), including 3 (60%) boys and 2 (40%) girls, with portomesenteric or portosystemic venous occlusion or recurrent stenosis, underwent balloon-expandable stent graft reconstruction. Presenting symptoms included acute variceal bleeding, without (n = 2, 40%) or with (n = 1, 20%) splenomegaly, and transfusion-dependent chronic melena (n = 1, 20%). One patient was asymptomatic (n = 1, 20%). Preprocedural imaging included Doppler ultrasound and contrast-enhanced computed tomography (CT) in all patients. Initial imaging showed 4 (80%) occlusions and 1 (20%) recurrent stenosis greater than 50%. Technical aspects of the reconstructions, technical successes, clinical outcomes and adverse events were recorded. Technical success was defined as completion of stent graft reconstruction. Adverse events were categorized according to Society of Interventional Radiology criteria. Clinical success was defined as resolution of the presenting symptoms and/or prevention of portal hypertensive sequela., Results: Venous reconstruction was technically successful in all five patients. Stent graft locations included the main portal vein in 2 (40%), the superior mesenteric vein in 1 (20%), autologous Meso-Rex shunt in 1 (20%) and splenocaval shunt in 1 (20%). Six stent grafts were placed (two stent grafts placed in a single patient). Stent grafts had a median diameter of 7 mm (range: 6-10 mm) and a median length of 59 mm (range: 19-79 mm). Median fluoroscopy time was 36.6 min (range: 13.4-95.8 min) and median air kerma was 301.0 mGy (range: 218.0-1,148.2 mGy). No adverse events occurred. Median clinical follow-up was 18 months (range: 6-29 months). Median imaging follow-up was 17 months (range: 2-29 months). Clinical success was achieved in all patients and maintained during the follow-up period. One patient required follow-up intervention with superior mesenteric vein side extension with a self-expanding bare metal stent due to perigraft stenosis detected on CT 3 months after stent placement. There were no stent graft occlusions., Conclusion: Portomesenteric and portosystemic venous reconstruction using balloon-expandable stent grafts in pediatric patients was feasible and clinically successful in this preliminary experience. Additional studies are warranted., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In pediatric liver transplantation, bile duct complications occur with a greater incidence than vascular anastomotic dysfunction and represent a major source of morbidity and mortality. While surgical re-anastomosis can reduce the need for retransplantation, interventional radiology offers minimally invasive and graft-saving therapies. The combination of small patient size and prevailing Roux-en-Y biliary enteric anastomotic techniques makes endoscopic retrograde cholangiopancreatography difficult if not impossible. Expertise in percutaneous management is therefore imperative. This article describes post-surgical anatomy, pathophysiology and noninvasive imaging of biliary complications. We review percutaneous techniques, focusing heavily on biliary access and interventions for reduced liver grafts. Subsequently we review the results and adverse events of these procedures and describe conditions that masquerade as biliary obstruction., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Retrospective studies have demonstrated the efficacy and safety of pediatric and adolescent transjugular intrahepatic portosystemic shunt (TIPS), but long-term outcomes warrant further investigation., Objective: To report on the development of hyperplastic hepatic nodular lesion development in children and young adults (<21 years) with TIPS patency >3 years., Materials and Methods: Eighteen children and young adults, including 10 (55.6%) females and 8 (44.4%) males, underwent TIPS creation with >3 years' patency and follow-up evaluation at a tertiary children's hospital. The mean age at the time of TIPS creation was 12.5±5.1 years (range: 1.5-20.0 years). The mean model for end-stage liver disease (MELD) at the time of TIPS creation was 8.1±1.6 (range: 6-11). Indications for TIPS creation included acute variceal bleeding (8/18, 44.4%), primary (1/18, 5.6%) or secondary (7/18, 38.9%) prevention of varices, portal vein thrombosis (1/18, 5.6%), and splenic sequestration (1/18, 5.6%). Technical successes, intra-procedural parameters, hemodynamic and clinical successes, TIPS patencies, adverse events, imaging evaluations, and follow-ups were recorded., Results: All (100%) TIPS placements were successful; however, a direct intrahepatic portosystemic shunt was created in one (5.6%) patient. Mean reduction of the portosystemic shunt gradient was 9.1±3.3 mmHg (range: 4-16 mmHg). Seventeen (94.4%) patients demonstrated clinical success with resolution of their initial clinical indication for TIPS placement. The 3-year TIPS primary, primary-assisted, and secondary patencies were 83.3% (15/18), 94.4% (17/18), and 100% (18/18), respectively. Two (11.1%) patients developed mild, medically controlled hepatic encephalopathy. One (5.6%) patient developed hepatopulmonary syndrome. Nine (50%) patients developed single or multiple hepatic nodules at a mean imaging surveillance time after TIPS of 4.4±3.0 years (range: 1.5-10.2 years). Six (33.3%) patients developed nodules >1 cm with imaging features most consistent with focal nodular hyperplasia or focal nodular hyperplasia-like nodules. The mean follow-up duration was 5.7±2.9 years (range: 3.0-13.1 years)., Conclusion: Long-term (>3 years) portosystemic shunting via TIPS is associated with the development of hepatic nodular lesions in children. Consequently, children with TIPS may need gray-scale assessment of hepatic parenchyma as part of routine ultrasound exams and extended imaging surveillance until more is understood regarding the natural history of induced nodularity.

Background: Ultrasound (US)-guided tunneled femoral peripherally inserted central catheters (PICCs) are a safe central venous access option in infants and neonates. Studies have shown, however, that femoral central venous access has the potential for high central line-associated bloodstream infection (CLABSI) rates with a significant increase in risk around line day 30, though no studies have evaluated these risks exclusively for tunneled femoral PICCs., Objective: The primary purpose of this study was to evaluate the relationship between line duration and the risk of CLABSI in tunneled femoral PICCs in children., Materials and Methods: Four hundred forty-five patients (196 females, 249 males; median age: 49.4 days; median weight: 3.7 kg) who underwent 573 tunneled femoral PICC placements or exchanges from Jan. 1, 2017, to Jan. 31, 2020, were included in the study. All tunneled femoral PICCs were placed using US technique and catheter specifications, including catheter size (French) and length (cm), were retrieved from the electronic medical record. The location of the PICC placement, the number of lumens, the laterality of placement, and the patient's age and weight were also recorded. Only non-mucosal barrier injury CLABSIs, according to the Centers for Disease Control and Prevention (CDC) definitions, were counted as CLABSI for this study. The number of central line days until a CLABSI event was analyzed with an accelerated failure time model using the exponential, Weibull, and log-normal distributions to determine the probability of a CLABSI over time, taking into consideration the recorded covariates., Results: Tunneled femoral PICC placements accounted for 14,855 line days, during which 20 non-mucosal barrier injury CLABSIs (CLABSI rate of 1.35 per 1,000 line days) occurred during the study period. The highest CLABSI rate occurred in PICCs placed in the neonatal intensive care unit (NICU) at 2.01 per 1,000 line days and the lowest occurred in PICCs placed in interventional radiology at 0.26 per 1,000 line days. Overall, PICCs placed outside of interventional radiology had a CLABSI rate of 1.72 per 1,000 line days. The CLABSI rate during the first 30 days a line was in situ was lower than the rate after 30 days (0.51 per 1,000 line days vs. 3.06 per 1,000 line days, respectively). Statistical modeling and hazard estimation using the Akaike information criterion corrected for small sample size (AICc)-average of log-normal, Weibull and exponential distributions demonstrate the daily risk of CLABSI rapidly increases from day 1 to day 30, with the risk remaining high for the duration of line days., Conclusion: While tunneled femoral PICCs are a relatively safe and effective central venous access alternative, the rate of CLABSI appears to rapidly increase with increasing line days until around day 30 and then remains high thereafter.

Background: Ultrasonography may reliably visualize both appropriately positioned and malpositioned femoral-approach catheter tips. Radiography may be used to confirm catheter tip position after placement, but its utility following intraprocedural ultrasound (US) catheter tip verification is unclear., Objectives: To report the utility of confirmatory radiographs after US-guided tunneled femoral central venous catheter (CVC) placements by interventional radiology in pediatric patients., Materials and Methods: A total of 484 pediatric patients underwent bedside US-guided tunneled femoral CVC placements in an intensive care setting at a single tertiary children's hospital between Jan. 1, 2016, and April 20, 2020. Technical success, adverse events, post-procedure radiographic practices and inter-modality catheter tip concordance were recorded. All radiographs were performed within 12 h of catheter placement., Results: The mean patient age was 175±508 days (range: 1 day to 19 years), including 257 (53.1%) males and 227 (46.9%) females. Of the 484 attempted placements, 472 (97.5%) were primary placements. Four hundred eighty-one (99.4%) placements were technically successful. There were three (0.6%) technical failures due to previously undiagnosed iliofemoral venous occlusive disease. Five (1.0%) adverse events occurred. Radiographs were obtained within 12 h of CVC placement in 171 (35.3%) patients, in 120 (70.2%) of whom the indication was recent catheter placement. All 171 (100%) post-placement radiographs showed catheter tip location concordance with the intra-procedural US. In one (0.2%) patient, in whom there was nonvisualization of a guidewire and clinical concern for malposition during US-guided placement, post-procedure radiographs, coupled with multiplanar venography, demonstrated inadvertent paravertebral venous plexus catheter placement., Conclusion: The concordance between intra-procedural US and confirmatory post-procedure radiographs of CVC placements by interventional radiology obviates the need for routine radiographs. Radiographs may be obtained in instances of proceduralist uncertainty or clinical concern.

Background: The safety and efficacy of US-guided lumbar puncture in children has been described. In the pediatric setting, children are frequently referred to interventional radiology only after a failed landmark-based attempt. Routine pre-procedure US in these children is useful to determine a safe level for subarachnoid access and to optimize success., Objective: To determine whether pre-procedure US improves technical success and safety of US-guided lumbar puncture., Materials and Methods: We included 47 children. Inclusion criteria were urgent US-guided lumbar puncture in pediatric patients <18 years old. Exclusion criteria were non-urgent lumbar punctures, children referred without an antecedent landmark-based attempt, lumbar punctures performed with fluoroscopic guidance, and procedures performed prior to introducing the diagnostic approach in 2017. We did not evaluate data pertaining to successful landmark-based lumbar punctures performed without subsequent need for additional attempts. We recorded technical successes, adverse events and relevant abnormalities identified on pre-procedural US., Results: Thirty-six US-guided lumbar punctures were performed with 100% technical success. Eleven children referred to interventional radiology did not undergo lumbar puncture because of unfavorable US findings or interval clinical improvement obviating the need for lumbar puncture. Thirty-six children underwent US evaluation of the thecal sac prior to potential intervention. Of these 36 with pre-procedural US studies, 12 demonstrated paucity of cerebrospinal fluid and 14 demonstrated an epidural hematoma. Fifteen children who underwent lumbar puncture had a "traumatic tap," classified as a mild adverse event. No moderate or severe adverse events were recorded., Conclusion: Limited spinal US following failed landmark-based lumbar punctures frequently identifies procedure-related complications and can augment patient selection for future image-guided lumbar punctures.

Background: Accurate and reproducible means of measuring the portosystemic gradient are essential for risk stratification and treatment of portal hypertension., Objective: To report the reliability of hepatic venous pressure gradients in children with intrahepatic veno-venous collateralization., Materials and Methods: Between January 2012 and December 2019 (96 months), 39 patients with native livers underwent wedge hepatic venography and hepatic venous pressure gradient measurements at a tertiary pediatric center. All archived images were reviewed for balloon isolation of the hepatic vein and hepatic vein-to-hepatic vein (HV-HV) collaterals. HV-HV collaterals were categorized as present on the basis of non-catheterized segmental venous opacification despite appropriate balloon isolation. Hepatic venous pressure gradient was defined as the difference of wedge and free hepatic venous pressures. Wedge portosystemic gradient was defined as the difference between wedge hepatic venous pressure and right atrial (RA) pressures. For patients subsequently undergoing portal venous catheterization, portosystemic gradient was defined as the difference between main portal vein and RA pressures., Results: Thirteen of 39 (33.3%) patients demonstrated HV-HV collaterals on wedge hepatic venography. The mean hepatic venous pressure gradient was 5.2±3.8 mmHg (range: 0-15 mmHg). The mean hepatic venous pressure gradient was 3.6±2.6 mmHg (range: 0-9 mmHg) in the presence of HV-HV collaterals and 5.9±4.2 mmHg (range: 1-15 mmHg) in the absence of HV-HV collaterals (P=0.043). Twelve (30.8%) patients were found to have varices: 10 gastroesophageal, 1 rectal and 1 stomal. The mean hepatic venous pressure gradient in patients with varices was 5.4±47 mmHg (range: 0-15 mmHg). For patients with varices, mean hepatic venous pressure gradient was 3.0±2.7 mmHg (range: 0-9 mmHg) in the presence of HV-HV collaterals and 10.3±4.1 mmHg (range: 5-15 mmHg) in the absence of HV-HV collaterals (P=0.004). Four (10.3%) patients had extrahepatic portal vein occlusion: 3 with cavernous transformation and 1 with type Ib Abernethy malformation. All patients with extrahepatic portal vein occlusion demonstrated HV-HV collaterals compared with 8 of 35 (22.9%) patients without extrahepatic portal vein occlusion (P=0.002). Four of 39 (10.3%) patients underwent direct portal pressure measurements: 3 via transhepatic and 1 via trans-splenic portal access. All had demonstrated HV-HV collaterals on wedged imaging. One had extrahepatic portal vein occlusion. The mean time between wedge portosystemic gradient and portosystemic gradient measurement was 3.75 days (range: 0-8 days). The mean wedge portosystemic gradient was 4.5±3.1 mmHg (range: 2-9 mmHg) and the mean portosystemic gradient was 14.5±3.7 mmHg (range: 12-20 mmHg) (P=0.006)., Conclusion: HV-HV collateralization is frequently observed in children undergoing wedged portal venography and leads to misrepresentative hepatic venous pressure gradients. All patients undergoing hepatic venous pressure gradient measurement should have wedged venography to identify HV-HV collaterals and to qualify measured pressures. Additional techniques to obtain representative pressures in the presence of HV-HV collaterals warrant further investigation.

Background: Published data describing the endovascular treatment of dysfunctional mesoportal and portosystemic shunts in the pediatric population are limited., Objective: We sought to describe the treatment and follow-up of such shunts managed by interventional radiology at a single pediatric hospital. We hypothesized that stenotic and occluded pediatric portosystemic and mesoportal shunts can be maintained patent by interventional radiology in the moderate term., Materials and Methods: We conducted a single-center retrospective study at a tertiary pediatric hospital. We included children with surgical mesoportal (meso-Rex) or portosystemic (mesocaval, splenorenal or splenocaval) shunts treated with attempted angioplasty or stenting from 2010 to 2018. Technical success was defined as catheterization and intervention upon the shunt with venographic evidence of flow improvement. The primary outcome variables were shunt patency at 1 month, 6 months, 12 months and 24 months post-procedure and freedom from reintervention., Results: Twenty pediatric patients (11 boys, 9 girls; mean age 8.25 years, range 1.3-17 years) met inclusion criteria. Fifty-two interventions (primary and reintervention) on 13 splenorenal, 3 meso-Rex, 2 mesocaval and 2 splenocaval shunts were performed because of evidence of shunt failure, including gastrointestinal bleeding, hypersplenism, or radiographic evidence of a flow defect. The 11 stenotic shunts were treated with 100% technical success, while the remaining 9 occluded shunts were treated with 66.7% technical success. The mean number of reinterventions was 1.9 (standard deviation [SD] = 3.1) per child, which did not differ between stenotic and occluded shunts (P=0.24). Primary patency at 1-month, 6-month, 12-month and 24-months follow-up visits was 17/17 (100%), 10/16 (62.5%), 7/15 (46.7%) and 4/10 (40%), respectively. However, 100% of shunts were either primary patent or primary-assisted patent by endovascular reintervention. There were no cases of shunt occlusion following initial technical success. Finally, the median freedom from reintervention duration was 387 days (SD=821 days)., Conclusion: Dysfunctional portosystemic surgical shunts are effectively managed by endovascular methods. While many shunts require reintervention, combined primary patency and assisted primary patency rates are excellent.

Background: The use of arterial closure devices in achieving femoral hemostasis has been well documented in adults but insufficiently studied in the pediatric population. An earlier study from our institution of 40 Angio-Seal devices in 38 patients concluded that the arterial closure device is safe in children with only a single minor complication. Ongoing experience with this device at our institution, however, suggests a higher rate of complication., Objective: To retrospectively evaluate the safety and efficacy of the Angio-Seal in a pediatric population., Materials and Methods: A retrospective analysis reviewed all cases in which the Angio-Seal was deployed from June 2011 to September 2017. Peri-procedural documentation was reviewed for pre-procedure labs, clinical effectiveness in achieving hemostasis and complications related to the use of this device. Logistic regression analysis was also used to evaluate the relationship between patient demographic, vessel size and indication for angiography, and the presence or absence of complications., Results: During the study period, 48 additional Angio-Seal devices were deployed in 41 consecutive patients. Five patients were excluded for being older than 18 years. The mean age of the patients was 13.3 years (range: 4-18 years) with 18 patients female. The mean common femoral artery diameter was 5.98 mm in short axis diameter (range: 4-9 mm). Complications were present in 6/43 cases (14%) including 3 minor and 3 major complications that included additional procedures. No significant relationship was identified between vessel size, age and the indication for angiography, and the rate of complication on logistic regression analysis., Conclusion: While percutaneous arterial closure devices can be efficacious for achieving hemostasis, our experience demonstrates a higher rate of complications in children, contrary to a previous report. The deployment of such devices should be performed with prejudice in this population.

Background: Image-guided percutaneous microwave ablation has been used to treat adult osteoid osteomas but has not been thoroughly evaluated in the pediatric population., Objective: To evaluate the technical feasibility and clinical efficacy of microwave ablation to treat osteoid osteomas in pediatric patients., Materials and Methods: The electronic medical record and imaging archive were reviewed for 24 consecutive patients who had undergone microwave ablation of osteoid osteomas between January 1, 2015, and May 31, 2018, at a single tertiary care pediatric hospital. All patients were diagnosed by clinical and imaging criteria, and referred by a pediatric orthopedic surgeon after failing conservative management with pain medication. The average age of the patients was 13.3 years (range: 3-18 years), and the average size of the osteoid osteoma nidus was 8.8 mm (range: 5-22 mm). Technical success was defined as placement of the microwave antenna at the distal margin of the lesion nidus and achievement of the target ablation temperature. Clinical findings were assessed pre- and post-ablation and clinical success was defined as complete relief of pain without pain medication at 1-month follow-up. The number and severity of complications were also documented., Results: Clinical success was achieved in 100% of patients (24/24), with all reporting complete cessation of pain medication use 1 week after treatment and 0/10 pain at 1 month. There were 4 minor complications (17%) including access site numbness and a minor soft-tissue infection. There were no major complications., Conclusion: Microwave ablation is a technically feasible and clinically effective treatment for pediatric osteoid osteomas.

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 × 10 9 /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·cm 2 and 12,453 Gy·cm 2 , 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.

Background: Data regarding transsplenic portal venous access for diagnostic imaging and endovascular intervention in children are limited, possibly due to concerns regarding high bleeding risks and resultant underutilization., Objective: To investigate the safety and utility of transsplenic splenoportography and portal venous interventions in children., Materials and Methods: A retrospective review was performed of all pediatric patients undergoing percutaneous transsplenic portal venous access and intervention at two large tertiary pediatric institutions between January 2012 and April 2017 was performed. Parameters assessed included procedural indications, procedural and relevant prior imaging, technical details of the procedures, laboratory values and clinical follow-up., Results: Transsplenic portal venous access was achieved in all patients. Diagnostic transsplenic splenoportography was performed in 22 patients and was 100% successful at providing the desired anatomical and functional information. Four transsplenic portal venous interventions were performed with 100% success: meso-Rex shunt angioplasty, snare targeted transjugular intrahepatic portosystemic shunt (TIPS) creation through cavernous transformation, pharmacomechanical thrombectomy for acute thrombosis, and transplant portal vein angioplasty. Intraperitoneal bleeding occurred in 2/26 (7.7%) and one case required transfusion (3.8%). No cases of hemorrhage were observed when transsplenic access size was 4 Fr or smaller., Conclusion: Transsplenic splenoportography in children is safe and effective when noninvasive imaging methods have yielded incomplete information. Additionally, a transsplenic approach has advantages for complex portal interventions. Bleeding risks are proportional to tract access size and may be mitigated by tract embolization.

Background: Disadvantages of fluoroscopically guided lumbar puncture include delivery of ionizing radiation and limited resolution of incompletely ossified posterior elements. Ultrasound (US) allows visualization of critical soft tissues and the cerebrospinal fluid (CSF) space without ionizing radiation., Objective: To determine the technical success and safety of US-guided lumbar puncture in pediatric patients., Materials and Methods: A retrospective review identified all patients referred to interventional radiology for lumbar puncture between June 2010 and June 2017. Patients who underwent lumbar puncture with fluoroscopic guidance alone were excluded. For the remaining procedures, technical success and procedural complications were assessed. Two hundred and one image-guided lumbar punctures in 161 patients were included. Eighty patients (43%) had previously failed landmark-based attempts., Results: One hundred ninety-six (97.5%) patients underwent lumbar puncture. Five procedures (2.5%) were not attempted after US assessment, either due to a paucity of CSF or unsafe window for needle placement. Technical success was achieved in 187 (95.4%) of lumbar punctures attempted with US guidance. One hundred seventy-seven (90.3%) were technically successful with US alone (age range: 2 days-15 years, weight range: 1.9-53.1 kg) and an additional 10 (5.1%) were successful with US-guided thecal access and subsequent fluoroscopic confirmation. Three (1.5%) cases were unsuccessful with US guidance but were subsequently successful with fluoroscopic guidance. Of the 80 previously failed landmark-based lumbar punctures, 77 (96.3%) were successful with US guidance alone. There were no reported complications., Conclusion: US guidance is safe and effective for lumbar punctures and has specific advantages over fluoroscopy in pediatric patients.

The purpose of the article is to evaluate the effects of mechanical complications, such as clogging or coiling, of gastrojejunostomy tubes on radiation exposure during exchange in the pediatric population. In this HIPAA-compliant and IRB-approved study, we retrospectively reviewed procedural records for patients undergoing gastrojejunostomy (GJ) tube exchange during a 4-month period in 2014. Success of the procedure, specifications of the tube, age, and sex of the patient as well as radiation exposure during the procedure were included. Radiation exposure was measured in fluoroscopy time and cumulative air kerma. Complications encountered during exchange were also recorded, if available. Patients presenting for gastrostomy to GJ conversions or combined procedures were excluded from the study. Ordinary and mixed effect linear regression models were used to test associations between GJ tube parameters, presence of mechanical complications, and fluoroscopy time and radiation dose. 146 patients undergoing 285 GJ exchanges met inclusion criteria over the 4-month study period (M:F 82:64). All exchanges were successful with 85 demonstrating a form of mechanical complication (44 coiled, 41 clogged). Of the reported GJ tube specifications, only tube length was significantly associated with mechanical complications (p < 0.001). The presence of mechanical complication was significantly associated with increased radiation exposure and fluoroscopy time (p < 0.0001). Mechanical complications of gastrojejunostomy tubes, such as clogging or coiling, are associated with increased radiation exposure during exchange. Strategies to decrease these complications, including re-siting the gastrostomy tract or placement of a surgical jejunostomy in the event of repeated coiling of a tube should be strongly considered.

Background: Nusinersen, the only treatment approved by the United States Food and Drug Administration for spinal muscular atrophy (SMA), is delivered intrathecally. Many children with SMA have extensive spinal instrumentation and deformities, often precluding the use of standard approaches for gaining intrathecal access. Furthermore the anatomical distortion that often occurs with rotoscoliosis can complicate the use of fluoroscopic guidance. Compared to fluoroscopy, CT affords superior guidance for complex needle placements. This opens up alternatives to the posterior (interlaminar) technique, including transforaminal and caudal approaches., Objective: This study describes the early results of technical success, complications and radiation dose of intrathecal delivery of nusinersen using cone-beam CT guidance with two-axis fluoroscopic navigational overlay., Materials and Methods: We conducted a retrospective review of 15 consecutive nusinersen injections performed in four children with SMA and extensive spinal hardware precluding standard posterior lumbar puncture techniques. These children were treated using transforaminal thecal access employing cone-beam CT with navigational overlay. We analyzed results including technical success, complications and total fluoroscopy time., Results: All procedures were technically successful. No major complications and one minor complication were reported; the minor complication was a post-procedural neuropathic headache that was attributed to procedural positioning and was treated successfully with gabapentin. The average procedural fluoroscopy time and air kerma were 1.9 min and 55.8 mGy, respectively., Conclusion: Cone-beam CT guidance with two-axis navigational overlay is a safe, effective method for gaining transforaminal intrathecal access in children with spinal abnormalities and hardware precluding the use of standard techniques.