Diagnostic Imaging for Retinoblastoma Cancer Staging: Guide for Providing Essential Insights for Ophthalmologists and Oncologists.

Retinoblastoma is the most common cause of all intraocular pediatric malignancies. It is caused by the loss of RB1 tumor suppressor gene function, although some tumors occur due to MYCN oncogene amplification with normal RB1 genes. Nearly half of all retinoblastomas occur due to a hereditary germline RB1 pathogenic variant, most of which manifest with bilateral tumors. This germline RB1 mutation also predisposes to intracranial midline embryonal tumors. Accurate staging of retinoblastoma is crucial in providing optimal vision-, eye-, and life-saving treatment. The AJCC Cancer Staging Manual has undergone significant changes, resulting in a universally accepted system with a multidisciplinary approach for managing retinoblastoma. The authors discuss the role of MRI and other diagnostic imaging techniques in the pretreatment assessment and staging of retinoblastoma. A thorough overview of the prevailing imaging standards and evidence-based perspectives on the benefits and drawbacks of these techniques is provided. Published under a CC BY 4.0 license. Test Your Knowledge questions for this article are available in the supplemental material.

Assessment of MR blood-oxygen-level-dependent (BOLD) cerebrovascular reactivity under general anesthesia in children with moyamoya.

BACKGROUND: Moyamoya is a progressive, non-atherosclerotic cerebral arteriopathy that may present in childhood and currently has no cure. Early diagnosis is critical to prevent a lifelong risk of neurological morbidity. Blood-oxygen-level-dependent (BOLD) MRI cerebrovascular reactivity (CVR) imaging provides a non-invasive, in vivo measure of autoregulatory capacity and cerebrovascular reserve. However, non-compliant or younger children require general anesthesia to achieve BOLD-CVR imaging. OBJECTIVE: To determine the same-day repeatability of BOLD-CVR imaging under general anesthesia in children with moyamoya. MATERIALS AND METHODS: Twenty-eight examination pairs were included (mean patient age = 7.3 ± 4.0 years). Positive and negatively reacting voxels were averaged over signals and counted over brain tissue and vascular territory. The intraclass correlation coefficient (ICC), Wilcoxon signed-rank test, and Bland-Altman plots were used to assess the variability between the scans. RESULTS: There was excellent-to-good (≥ 0.59) within-day repeatability in 18 out of 28 paired studies (64.3%). Wilcoxon signed-rank tests demonstrated no significant difference in the grey and white matter CVR estimates, between repeat scans (all p-values > 0.05). Bland-Altman plots of differences in mean magnitude of positive and negative and fractional positive and negative CVR estimates illustrated a reasonable degree of agreement between repeat scans and no systematic bias. CONCLUSION: BOLD-CVR imaging provides repeatable assessment of cerebrovascular reserve in children with moyamoya imaged under general anesthesia.

Ancillary investigations for death determination in infants and children: a systematic review and meta-analysis.

PURPOSE: We performed a systematic review and meta-analysis to determine the diagnostic test accuracy of ancillary investigations for declaration of death by neurologic criteria (DNC) in infants and children. SOURCE: We searched MEDLINE, EMBASE, Web of Science, and Cochrane databases from their inception to June 2021 for relevant randomized controlled trials, observational studies, and abstracts published in the last three years. We identified relevant studies using Preferred Reporting Items for Systematic Reviews and Meta-Analysis methodology and a two-stage review. We assessed the risk of bias using the QUADAS-2 tool, and applied Grading of Recommendations Assessment, Development, and Evaluation methodology to determine the certainty of evidence. A fixed-effects model was used to meta-analyze pooled sensitivity and specificity data for each ancillary investigation with at least two studies. PRINCIPAL FINDINGS: Thirty-nine eligible manuscripts assessing 18 unique ancillary investigations (n = 866) were identified. The sensitivity and specificity ranged from 0.00 to 1.00 and 0.50 to 1.00, respectively. The quality of evidence was low to very low for all ancillary investigations, with the exception of radionuclide dynamic flow studies for which it was graded as moderate. Radionuclide scintigraphy using the lipophilic radiopharmaceutical 99mTc-hexamethylpropyleneamine oxime (HMPAO) with or without tomographic imaging were the most accurate ancillary investigations with a combined sensitivity of 0.99 (95% highest density interval [HDI], 0.89 to 1.00) and specificity of 0.97 (95% HDI, 0.65 to 1.00). CONCLUSION: The ancillary investigation for DNC in infants and children with the greatest accuracy appears to be radionuclide scintigraphy using HMPAO with or without tomographic imaging; however, the certainty of the evidence is low. Nonimaging modalities performed at the bedside require further investigation. STUDY REGISTRATION: PROSPERO (CRD42021278788); registered 16 October 2021.

RéSUMé: OBJECTIF: Nous avons réalisé une revue systématique et une méta-analyse pour déterminer la précision des tests diagnostiques des examens auxiliaires pour la déclaration du décès selon des critères neurologiques (DCN) chez les nourrissons et les enfants. SOURCES: Nous avons effectué des recherches dans les bases de données MEDLINE, EMBASE, Web of Science et Cochrane de leur création jusqu'en juin 2021 pour trouver des études randomisées contrôlées, des études observationnelles et des résumés pertinents publiés au cours des trois dernières années. Nous avons identifié les études pertinentes utilisant la méthodologie PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) et une revue en deux étapes. Nous avons évalué le risque de biais en utilisant l'outil QUADAS-2 et appliqué la méthodologie GRADE (Grading of Recommendations Assessment, Development and Evaluation) afin d'évaluer la certitude des données probantes. Un modèle à effets fixes a été utilisé pour méta-analyser les données de sensibilité et de spécificité regroupées pour chaque examen auxiliaire avec au moins deux études. CONSTATATIONS PRINCIPALES: Trente-neuf manuscrits admissibles évaluant 18 examens auxiliaires uniques (n = 866) ont été identifiés. La sensibilité et la spécificité variaient de 0,00 à 1,00 et de 0,50 à 1,00, respectivement. La qualité des données probantes était faible à très faible pour tous les examens auxiliaires, à l'exception des études de circulation nucléaire dynamique, pour lesquelles elle a été classée comme modérée. La scintigraphie nucléaire à l'aide du produit radiopharmaceutique lipophile 99mTc- hexa-méthyl-propylène amine oxime (HMPAO) avec ou sans imagerie tomographique était à la base des examens auxiliaires les plus précis, avec une sensibilité combinée de 0,99 (intervalle de densité le plus élevé [IDE] à 95 %, 0,89 à 1,00) et une spécificité de 0,97 (IDE à 95 %, 0,65 à 1,00). CONCLUSION: L'examen auxiliaire pour un DCN chez les nourrissons et les enfants offrant la plus grande précision semble être la scintigraphie nucléaire utilisant le HMPAO avec ou sans imagerie tomographique; cependant, la certitude des données probantes est faible. Les modalités sans imagerie réalisées au chevet du patient nécessitent un examen plus approfondi. Enregistrement de l'étude: PROSPERO (CRD42021278788); enregistrée le 16 octobre 2021.

Local reference and achievable dose levels for vascular and enterostomy access procedures in pediatric interventional radiology.

BACKGROUND: Knowledge of radiation quantities delivered in routine practice is an essential responsibility of a pediatric interventional radiology department. OBJECTIVE: To review radiation indices in frequently performed vascular and enterostomy access procedures at a quaternary pediatric hospital to formulate dosimetric reference levels and achievable levels. MATERIALS AND METHODS: A retrospective review of patient demographics, procedure information and quantitative dose metrics over a 2-year period was performed. Dosimetric details for common procedures (central line insertions, gastrostomy/gastrojejunostomy insertions and maintenance) were evaluated, correlated with demographic data and stratified across five weight groups (0-5 kg, 5-15 kg, 15-30 kg, 30-50 kg, 50-80 kg). Achievable (50th percentile) and reference (75th percentile) levels with confidence intervals were established for each procedure. RESULTS: Within the evaluation period, 3,165 studies satisfied the inclusion criteria. Five were classified as device insertions (peripherally inserted central catheter, n=1,145; port-a-catheter, n=321; central venous line, n=285; gastrostomy-tube [G-tube], n=262, and gastrojejunostomy-tube [GJ-tube], n=66), and two were classified as maintenance procedures (G-tube, n=358, and GJ-tube, n=728, checks, exchanges and reinsertions). Representative reference and achievable levels were calculated for each procedure category and weight group. CONCLUSION: This work highlights the creation of local reference and achievable levels for common pediatric interventional procedures. These data establish a dosimetric reference to understand the quantity of radiation routinely applied, allowing for improved relative radiation risk assessment and enriched communication to interventionalists, health care providers, parents and patients.

Use of radial access sheaths for transfemoral neuroendovascular procedures in children.

PURPOSE: Pediatric neuroendovascular procedures require special considerations. Given small vessel sizes, risk for arterial injury must be weighed against use of larger devices, with the diameter of the sheath being a known association with arterial complications. We recently transitioned to using thin-walled radial sheaths for transfemoral angiography in children, given their lower profile. Here, we report on these sheaths' technical success and complications, comparing against a historical cohort where regular vascular sheaths were employed. METHODS: We retrospectively recorded patient and procedural data from 168 consecutive procedures from September 2017 to January 2019 when radial-specific sheaths were exclusively used at our tertiary pediatric hospital. These results were compared to data from September 2015 to January 2017, when regular vascular sheaths were exclusively used in 152 consecutive procedures. Statistical analysis was performed using unpaired t test or chi-square test, with p < 0.05 considered statistically significant. RESULTS: Patient characteristics (age, sex, weight) were not statistically different between the case and control group. No significant differences were found in the procedural data with the exception of heparin use which was higher in the radial-sheath cohort. There was a decrease in the rate of complications in the case group (1.2%) versus control group (2.6%), though not statistically different. CONCLUSION: Radial-specific sheaths have numerous beneficial characteristics that make them well-suited to the pediatric population. In our study, we show that radial sheaths are equally effective and safe perioperatively. Follow-up research may show if radial sheaths used transfemorally decrease long-term complications such as limb-length discrepancy and mortality.

Radiation-induced intracranial aneurysm presenting with acute hemorrhage in a child treated for medulloblastoma.

Radiation-associated aneurysms are rare, difficult to treat, and associated with high morbidity and mortality when ruptured, compared with aneurysms unrelated to radiation treatment. We present a 16-year-old patient with a radiation-induced intracranial aneurysm arising from the left posterior inferior cerebellar artery (PICA), 10 years following radiotherapy for medulloblastoma. The patient successfully underwent endovascular coil embolization of the parent artery across the neck of the aneurysm. CT angiography and MRI in the days following the procedure demonstrated maintained flow in the anterior and lateral medullary PICA segments with no brainstem infarct.

Image-guided chest tube drainage in the management of chylothorax post cardiac surgery in children: a single-center case series.

BACKGROUND: In children, chylothorax post cardiac surgery can be difficult to treat, may run a protracted course, and remains a source of morbidity and mortality. OBJECTIVE: To analyze the experience with percutaneous image-guided chest-tube drainage in the management of post-cardiac-surgery chylothoraces in children. MATERIALS AND METHODS: We conducted a single-center retrospective case series of 37 post-cardiac-surgery chylothoraces in 34 children (20 boys; 59%), requiring 48 drainage procedures with placement of 53 image-guided chest tubes over the time period 2004 to 2015. We analyzed clinical and procedural details, adverse events and outcomes. Median age was 0.6 years, median weight 7.2 kg. RESULTS: Attempted treatments of chylothoraces prior to image-guided chest tubes included dietary restrictions (32/37, 86%), octreotide (12/37, 32%), steroids (7/37, 19%) and thoracic duct ligation (5/37, 14%). Image-guided chest tubes (n=43/53, 81%) were single unilateral in 29 children, bilateral in 4 (n=8/53, 15%), and there were two ipsilateral tubes in one (2/53, 4%). Effusions were isolated, walled-off, in 33/53 (62%). In 20/48 procedures (42%) effusions were septated/complex. The mean drainage through image-guided chest tubes was 17.3 mL/kg in the first 24 h, and 13.4 mL/kg/day from diagnosis to chest tube removal; total mean drainage from all chest tubes was 19.6 mL/kg/day. Nine major and 27 minor maintenance procedures were required during 1,207 tube-days (rate: 30 maintenance/1,000 tube-days). Median tube dwell time was 21 days (range 4-57 days). There were eight mild adverse events, three moderate adverse events and no severe adverse events related to image-guided chest tubes. Radiologic resolution was achieved in 26/37 (70%). Twenty-three children (68%) survived to discharge; 11 children (32%) died from underlying cardiac disease. CONCLUSION: Management of chylothorax post-cardiac-surgery in children is multidisciplinary, requiring concomitant multipronged approaches, often through a protracted course. Multiple image-guided chest tube drainages can help achieve resolution with few complications. Interventional radiology involvement in tube care and maintenance is required. Overall, mortality remains high.

Treatment Strategies and Related Outcomes for Brain Arteriovenous Malformations in Children: A Systematic Review and Meta-Analysis.

OBJECTIVE. The objective of this study was to assess the available evidence in the literature regarding treatment outcomes for pediatric patients with brain arteriovenous malformation (bAVM) with the aim of providing practice guidelines for treatment decisions and highlighting research areas that need attention. MATERIALS AND METHODS. Keyword searches for studies published from January 1, 1981, to April 16, 2018, were performed in MEDLINE, Embase, and Web of Science. Predefined inclusion criteria were used to identify studies. Poisson regression analysis for associations between patient and bAVM characteristics and treatment outcomes. RESULTS. We identified 34 articles comprising 2158 children with bAVM who underwent treatment or observation. The mean age of the study cohort was 12.0 ± 1.6 (SD) years, and 48.1% of the patients were female; 64.3% of bAVMs were hemorrhagic at presentation. The mean follow-up was 50.6 ± 32.3 months. Overall, the meta-analysis of pooled data showed an obliteration rate of 69.8% (95% CI, 62.9-75.9%), recurrence rate of 2.2% (95% CI, 1.1-4.3%), and mortality rate of 2.4%. The pooled complication rate was 22.5% (95% CI, 15.7-31.1%) after surgery, 26.4% (95% CI, 15.2-41.9%) after embolization, and 27.1% (95% CI, 18.1-38.4%) after radiosurgery. Mortality was not associated with age, sex, or hemorrhage; however, recurrence after treatment was inversely associated with age. Complication and mortality rates were reduced for multimodal treatments. For patients with bAVM treated with observation only, complication and mortality rates were 35.9% and 23.5%, respectively. CONCLUSION. Multimodality treatments for pediatric bAVM had lower mortality and complication rates than individual treatments. However, there is a lack of evidence for long-term outcomes. The mortality rate was highest in conservatively managed patients (i.e., observation only). Further research directly comparing different treatment modalities for recurrence and complications is warranted. Gathering data prospectively through multiinstitutional registries will be key to provide strong evidence.

Correction to: Venous pathologies in paediatric neuroradiology: from foetal to adolescent life.

The original version of this article unfortunately contained a referencing omission. Figure 11 is reused from the original publication of Figure 10 of Gunny and Lin [1].

Venous pathologies in paediatric neuroradiology: from foetal to adolescent life.

The interpretation of cerebral venous pathologies in paediatric practice is challenging as there are several normal anatomical variants, and the pathologies are diverse, involving the venous system through direct and indirect mechanisms. This paper aims to provide a comprehensive review of these entities, as their awareness can avoid potential diagnostic pitfalls. We also propose a practical classification system of paediatric cerebral venous pathologies, which will enable more accurate reporting of the neuroimaging findings, as relevant to the underlying pathogenesis of these conditions. The proposed classification system comprises of the following main groups: arterio-venous shunting-related disorders, primary venous malformations and veno-occlusive disorders. A multimodal imaging approach has been included in the relevant subsections, with a brief overview of the modality-specific pitfalls that can also limit interpretation of the neuroimaging. The article also summarises the current literature and international practices in terms of management options and outcomes in specific disease entities.

The role of MRA in pediatric sickle cell disease with normal transcranial Doppler imaging velocities.

PURPOSE: The purpose of this study was to determine the additional information provided by Magnetic Resonance Angiography (MRA) in pediatric sickle cell disease (SCD) patients with normal Transcranial Doppler imaging (TCDI) examinations. METHODS: This cohort study included all pediatric SCD patients over an 18-year period who had no history of stroke and had normal TCDI examinations and subsequently underwent MRA. Routine TCDI inclusive of time-averaged mean of maximum velocities (TAMMV) were assesses and compared with tortuosity on MRA and silent infarct on MRI. RESULTS: 86 children (52.3% female; mean age 8.7 ± 3.5years) were included. There were 77 patients (89.5%) with Hb-SS disease and 9(10.4%) with HB-S beta-thalassemia. All patients had normal TAMMV (<170 cm/s) on TCDI. 76/86 (88.3%) patients also had one or more velocity readings <70 cm/s, albeit none in the middle cerebral arteries. Posterior cerebral arteries had the lowest velocities, <70 cm/s in 51.7% (right) and 60.9% (left). Silent MRI infarcts were seen in 27/86 (31.4%) patients. No new lesions were identified on follow-up MRI. Although mild vascular tortuosity was appreciated in 31/86 (36.0%) of the patients, there were no steno-occlusive lesions in the circle of Willis. CONCLUSIONS: TCDI and MRA are routinely performed for non-invasively evaluating intracranial vascular abnormalities in children with SCD. In SCD children with no history of TIA or stroke, MRA following a normal TCDI examination is unlikely to show vascular abnormality. However, almost a third of these patients show silent infarcts on MRI, unassociated with MRA changes.

Anatomical Venous Variants in Children With Cerebral Sinovenous Thrombosis.

Background and Purpose- Literature is sparse on the frequency and significance of anatomical venous variants (AVVs) in pediatric cerebral sinovenous thrombosis (CSVT). Methods- We retrospectively reviewed children with CSVT and controls undergoing computed tomography/magnetic resonance venography from January 2008 to 2014. Clinical features examined included raised intracranial pressure, risk factors, and treatment. Radiological features examined included CSVT location, presence and type of AVVs, hemorrhagic venous infarction, and venous collateralization. Clinical outcome was measured by the pediatric stroke outcome measure and radiological outcome by thrombus recanalization. Results- Fifty-one children with CSVT were identified. Twenty-two (43%) had AVVs at presentation. Nineteen (86%) had hypoplasia/absence of major dural sinus, 5 (23%) had persistent fetal structures, 3 (14%) had duplications/fenestrations, and 1 (5%) had disconnected superficial and deep venous systems. Controls had a slightly higher but nonsignificant prevalence 26 (51%) of AVVs. No significant clinical and radiological differences were observed between children with CSVT and AVVs compared with those with typical venous anatomy. Conclusions- AVVs are seen in many children with and without CSVT and do not seem to alter the presentation or clinical course. The influence of these variations on the brain's ability to tolerate venous congestion because of thrombosis merits further study.

Quantitative color-coded digital subtraction neuroangiography for pediatric arteriovenous shunting lesions.

BACKGROUND: Several complex pediatric neurovascular conditions are amenable to endovascular treatment. Given the unique anatomical and physiological challenges in children, there is an ongoing need for tools and techniques that provide accurate information for treatment planning, while minimizing exposure to ionizing radiation and contrast. This is more so for neonates and infants with high-flow arteriovenous (AV) shunts that are challenging to assess using conventional techniques. OBJECTIVE: In this brief report, we describe, through representative cases, the potential role of quantitative color-coded digital subtraction angiography (qDSA) in neuroendovascular procedures in children with high-flow AV shunting lesions. METHODS: Images were obtained using an ArtisQ biplane system (Siemens Healthineers, Erlangen, Germany). Post-processing was performed at a dedicated workstation (Syngo, Siemens) using the iFlow module to generate color-coded maps of individual digital subtraction angiography runs. CONCLUSION: Color-coded qDSA provides real-time quantitative information in high-flow AV shunting neurovascular lesions. This can potentially help direct treatment choices, optimize endovascular treatment protocols, monitor outcomes, and determine treatment end points.

Evaluation of implanted venous port-a-caths in children with medical complexity and neurologic impairment.

BACKGROUND: Children with medical complexity and associated neurologic impairment frequently face difficulties with venous access. Intermittently they require urgent intravenous administration of fluids and medication. OBJECTIVE: To analyze the use of implanted port-a-caths in children with medical complexity who have neurologic impairment and difficult venous access. MATERIALS AND METHODS: We performed a single-center observational study of port-a-caths placed by interventional radiologists in children with medical complexity with neurologic impairment. We analyzed peripheral intravenous access attempts, peripheral intravenous starts, peripheral intravenous complications, alternative temporary central venous access devices, port-a-cath insertions, catheter days, access days, port-a-cath-related complications, hospital admissions and emergency department visits. We compared the year pre port-a-cath to the year post port-a-cath. RESULTS: Twenty-one children with medical complexity with neurologic impairment (10 boys, 11 girls; median age 4.1 years; median weight 13.7 kg) underwent 26 port-a-cath insertions (median catheter days 787). In the year post port-a-cath compared to pre port-a-cath there was a highly significant reduction (P<0.001) in numbers of peripheral intravenous attempts, peripheral intravenous starts and skin punctures; and a significant reduction (P<0.05) in need for other devices, number of emergency department visits, emergency department visits resulting in hospital admissions, and total admissions. Adverse events were graded as mild (n=18), moderate (n=6) and severe (n=0). CONCLUSION: Port-a-cath placement in children with medical complexity with neurologic impairment significantly reduced all peripheral intravenous attempts, peripheral intravenous starts, skin punctures, total number of emergency department visits, visits culminating in admission, and total number of inpatient admissions. Advantages must be considered against potential port-a-cath-related adverse events.

Management of a Large Congenital Hemangioma Obstructing Visual Axis: A Case Report and Review of Literature.

Congenital hemangiomas comprise a subset of vascular tumors with clinicopathologic features that are distinct from the more common infantile hemangioma. The authors present a patient with a large congenital hemangioma involving the forehead and brow which obstructed the visual axis and created significant risk for deprivational amblyopia. Management of the congenital hemangioma involved customized headgear to clear the visual axis and early vascular embolization of feeder vessels with the subsequent successful surgical resection at 23 days of life.A large amblyogenic congenital hemangioma required a multidisciplinary approach involving early vascular embolization of feeder vessels and subsequent surgical resection at 23 days of life.

Arterial Wall Imaging in Pediatric Stroke.

BACKGROUND AND PURPOSE: Arteriopathy is common in childhood arterial ischemic stroke (AIS) and predicts stroke recurrence. Currently available vascular imaging techniques mainly image the arterial lumen rather than the vessel wall and have a limited ability to differentiate among common arteriopathies. We aimed to investigate the value of a magnetic resonance imaging-based technique, namely noninvasive arterial wall imaging (AWI), for distinguishing among arteriopathy subtypes in a consecutive cohort of children presenting with AIS. METHODS: Children with confirmed AIS and magnetic resonance angiography underwent 3-Tesla AWI including T1-weighted 2-dimensional fluid-attenuated inversion recovery fast spin echo sequences pre- and post-gadolinium contrast. AWI characteristics, including wall enhancement, wall thickening, and luminal stenosis, were documented for all. RESULTS: Twenty-six children with AIS had AWI. Of these, 9 (35%) had AWI enhancement. AWI enhancement was associated with anterior circulation magnetic resonance angiography abnormality and cortical infarction in 8 of 9 (89%) children and normal magnetic resonance angiography with posterior circulation subcortical infarction in 1 (1 of 9; 11%) child. AWI enhancement was not seen in 17 (65%), 10 (59%) of whom had an abnormal magnetic resonance angiography. Distinct patterns of pre- and postcontrast signal abnormality were demonstrated in the vessel wall in the region of interest in children with transient cerebral arteriopathy, arterial dissection, primary central nervous system angiitis, dissecting aneurysm, and cardioembolic stroke. CONCLUSIONS: AWI is a noninvasive, high-resolution magnetic resonance AWI technique, which can be successfully used in children presenting with AIS. Patterns of AWI enhancement are recognizable and associated with specific AIS pathogeneses. Further studies are required to assess the additional diagnostic utility of AWI over routine vascular imaging techniques, in childhood AIS.

Splanchnic, Thoracoabdominal, and Cerebral Blood Flow Volumes in Healthy Children and Young Adults in Fasting and Postprandial States: Determining Reference Ranges by Using Phase-Contrast MR Imaging.

Purpose To estimate reference ranges for blood flow volume (BFV) in major splanchnic, thoracoabdominal, and neck vessels by using phase-contrast magnetic resonance (MR) imaging in children and young adults in fasting and postprandial states. Materials and Methods In this institutional research ethics board-approved prospective study, healthy volunteers underwent phase-contrast MR imaging in a fasting state and again after a standardized meal. BFV values were reported as medians and ranges, and postmeal to premeal BFV ratios were calculated. BFVs in volunteers divided into two groups according to age (≤18 years old and >18 years old) were compared by using the Mann-Whitney test adjusted for multiple comparisons. Linear regression for internal validation of BFV and Pearson correlation and Bland-Altman analysis for interobserver agreement were used. Results Reference ranges for BFVs were estimated in 39 volunteers (23 male and 16 female; mean age, 21.2 years ± 8.5; range, 9-40 years) and were indexed according to body surface area, with internal validation (R2 = 0.84-0.92) and excellent interobserver agreement (R2 = 0.9928). There was an almost 30% increase in total abdominal BFV (P < .0001) in response to a meal, which was the result of a threefold increase in superior mesenteric artery BFV (P < .0001). BFV after the meal remained unaffected in the celiac artery and cerebral circulation. Significantly higher normalized BFVs in the cerebral circulation were measured in children with both preprandial (P = .039) and postprandial (P = .008) status than those in adults. Conclusion Reference ranges for BFVs and changes in BFVs in response to a meal in major splanchnic, thoracoabdominal, and neck vessels were estimated by using phase-contrast MR imaging in healthy volunteers to allow hemodynamic assessment of children and young adults with various diseases. © RSNA, 2017 Online supplemental material is available for this article.

CT reconstruction and MRI fusion of 3D rotational angiography in the evaluation of pediatric cerebrovascular lesions.

PURPOSE: Complex neurovascular lesions in children require precise anatomic understanding for treatment planning. Although 3DRA is commonly employed for volumetric reformation in neurointerventional procedures, the ability to reconstruct this data into CT-like images (3DRA-CT) is not widely utilized. This study demonstrates the feasibility and usefulness of 3DRA-CT and subsequent MRI fusion for problem solving in pediatric neuroangiography. METHODS: This retrospective study includes 18 3DRA-CT studies in 16 children (age 9.6 ± 3.8 years, range 2-16 years) over 1 year. After biplane 2D-digital subtraction angiography (DSA), 5-second 3DRA was performed with selective vessel injection either with or without subtraction. Images were reconstructed into CT sections which were post-processed to generate multiplanar reformation (MPR) and maximum intensity projection (MIP) images. Fusion was performed with 3D T1 MRI images to precisely demonstrate neurovascular relationships. Quantitative radiation metrics were extracted and compared against those for the entire examination and for corresponding biplane 2D-DSA acquisitions. RESULTS: In all 18 cases, the 3DRA procedure and MRI fusion were technically successful and provided clinically useful information relevant to management. The unsubtracted and subtracted 3DRA acquisitions were measured to deliver 5.9 and 132.2%, respectively, of the mean radiation dose of corresponding biplane 2D-DSA acquisitions and contributed 1.2 and 12.5%, respectively, to the total procedure dose. CONCLUSION: Lower radiation doses, high spatial resolution, and multiplanar reformatting capability make 3DRA-CT a useful adjunct to evaluate neurovascular lesions in children. Fusing 3DRA-CT data with MRI is an additional capability that can further enhance diagnostic information.

Measuring hemoglobin prior to early discharge without routine surveillance ultrasound after percutaneous native renal biopsy in children.

BACKGROUND: We aimed to evaluate the role of post-procedural hemoglobin (hb), without pre-discharge ultrasound (US), after US-guided renal biopsy in children. METHODS: A retrospective review was conducted of consecutive outpatient native kidney biopsies over an 8-year period. Procedures were performed under real-time US guidance. Data collected included number of passes, presence and size of perinephric hematoma, age, body mass index (BMI), blood pressure (BP), fasting status, hb and platelets. Continuous variables were expressed as mean ± standard deviation, group differences were tested with Student's unpaired t test and analysis of variance and correlations were assessed using Pearson's r. Significance was defined as p < 0.05. Hb changes (g/L), percentage hb (%hb) change, hematoma size and positive and negative predictive values (PPV, NPV, respectively) were analyzed. RESULTS: A total of 330 procedures in 300 children (141 females, mean age 11.2 ± 4.30 years) were analyzed. Post-procedural hematoma occurred in 63%. There was a significant (p = 0.0001) post-procedural hb decrease of 6.3 ± 5.5 g/L and %hb decrease of 4.56 ± 4.01%. Fasting during pre-procedural hb estimation and procedural hematoma was associated with a greater hb drop. A ≥10% hb drop had 73% PPV for repeat blood work and US and a 17% PPV for admission, whereas a <10% hb drop had a NPV of 84% and 98%, respectively. Hb change showed a weak correlation with age, and hematoma size showed a weak inverse correlation with platelet count, but no correlation with BMI, number of passes or BP. CONCLUSIONS: Bleeding complications from US-guided native kidney biopsies in pediatric outpatients can be safely followed by a complete blood count at 6 h post procedure. A 10% hb decrease is strongly associated with requirement for further testing and/or admission.