The comparison of magnetic resonance and fluoroscopic imaging options in the preoperative assessment of boys with anorectal malformations and a colostomy.

BACKGROUND: In recent decades, magnetic resonance imaging (MRI) has gained prominence as a standard diagnostic method for preoperative assessment in patients with anorectal malformations and a colostomy, with the potential to replace the classic fluoroscopic distal pressure colostogram (FDPC). Three MRI techniques are available: MRI-distal pressure colostogram with gadolinium (MRI-DPCG) or saline (MRI-DPCS) instillation into the colostomy and native MRI without colostomy instillation. OBJECTIVE: To evaluate and compare the diagnostic accuracy of MRI (native MRI, MRI-DPCG and MRI-DPCS) in the preoperative workup of boys with an anorectal malformation and a colostomy and to compare it to FDPC. MATERIALS AND METHODS: Sixty-two boys with preoperative MRI using one of the three approaches and 43 with FDPC met the inclusion criteria for this retrospective study. The presence and localization of rectal fistulas according to the Krickenbeck classification were evaluated and compared with intraoperative findings. RESULTS: The accuracy of fistula detection for MRI in general (regardless of the technique), MRI-DPCS, MRI-DPCG, native MRI and FDPC was 95% (59/62, P<0.001), 100% (12/12, P=0.03), 100% (30/30, P<0.001), 85% (17/20, P=0.41) and 72% (31/43, P=0.82), respectively. The accuracy of describing fistula type in patients with a correctly detected fistula using these methods was 96% (45/47, P<0.001), 100% (9/9, P<0.001), 100% (23/23, P<0.001), 87% (13/15, P<0.001) and 67% (13/21, P=0.002), respectively. CONCLUSION: MRI is a reliable method for detecting and classifying fistulas in boys with an anorectal malformation and a colostomy and can be considered the modality of first choice for preoperative workup.

Evaluation of the growth rates and related prognostic factors in radiation-induced meningiomas.

PURPOSE: Literature dedicated to growth patterns and growth rate influencing factors of radiation-induced meningiomas (RIMs) is limited. To deliver new insights into the topic, a volumetric growth analysis of RIMs was performed. METHODS: This single-center, retrospective cohort study included patients diagnosed with intracranial meningioma who received radiation treatment at least > 5 years before the RIM diagnosis. Volumetric analysis of individual RIMs was performed using 3D volumetry at the time of RIM diagnosis and during follow-up. RIM growth was determined by calculating absolute (AGR), and relative (RGR) growth rates. Prognostic factors associated with RIM growth were evaluated. RESULTS: A total of 26 patients with 33 meningiomas were enrolled in the study and radiologically/clinically followed up during a median duration of 5.6 years (IQR 3.9-8.8 years). Median AGR was 0.19 cm3 per year and the median RGR was 34.5% per year. Surgically managed RIMs were more likely fast-growing compared to observed ones based on the AGR (p < 0.002). The recurrence rate after total resection was 14.3%. Younger age at RIM diagnosis was associated with higher tumor growth (RGR ≥ 30%, p = 0.040). A significant correlation was found between the length of latency period and the RGR (p = 0.005). CONCLUSION: To diagnose RIM as early as possible comprehensive MRI surveillance is required. Younger patients with shorter latency periods may profit from shortened MRI intervals, with further management being dependent on the growth rate and eventual symptomatology.

Predictors of postoperative complications and functional outcomes in pediatric patients with surgically treated fourth ventricle tumors.

BACKGROUND: Tumors of the fourth ventricle are frequently treated pathologies in pediatric neurosurgery. Data regarding predictors for permanent neurological deficits, long-term functional outcomes, cerebellar mutism (CM), the extent of resection (EOR), and oncological outcomes are scarce. We attempt to contribute to this topic with an analysis of our institutional cohort. METHODS: A retrospective single-center study of patients aged ≤ 19 years who underwent primary surgical resection of a fourth ventricular tumor over a 15-year period (2006-2021). Predictors analyzed included age, gender, surgical approach, anatomical pattern, tumor grade, EOR, tumor volume, and others as appropriate. RESULTS: One hundred six patients were included (64 males, mean age 7.3 years). The rate of permanent neurological deficit was 24.2%; lateral tumor extension (p = 0.036) and tumor volume greater than 38 cm3 (p = 0.020) were significant predictors. The presence of a deficit was the only significant predictor of reduced (less than 90) Lansky score (p = 0.005). CM occurred in 20.8% of patients and was influenced by medulloblastoma histology (p = 0.011), lateral tumor extension (p = 0.017), and male gender (p = 0.021). No significant difference between the transvermian and telovelar approach in the development of CM was detected (p = 0.478). No significant predictor was found for the EOR. EOR was not found to be a significant predictor of overall survival for both low-grade and high-grade tumors; however, gross total resection (GTR) was protective against tumor recurrence compared to near-total or subtotal resection (p < 0.001). In addition, survival was found to be better in older patients (≥ 7.0 years, p = 0.019). CONCLUSION: The overall rate of postoperative complications remains high due to the eloquent localization. Older patients (> 7 years) have been found to have better outcomes and prognosis. Achieving GTR whenever feasible and safe has been shown to be critical for tumor recurrence. CM was more common in patients with medulloblastoma and in patients with tumors extending through the foramen of Luschka. The telovelar approach uses a safe and anatomically sparing corridor; however, it has not been associated with a lower incidence of CM and neurological sequelae in our series, showing that each case should be assessed on an individual basis.

Anastomotic stricture prediction in patients with esophageal atresia with distal fistula.

PURPOSE: To investigate potential early risk factors for anastomotic stricture formation and assess the predictive role of post-operative esophagrams. METHODS: A retrospective study of patients with esophageal atresia with distal fistula (EA/TEF) operated between 2011 and 2020. Fourteen predictive factors were tested for stricture development. Esophagrams were used to calculate early (SI1) and late (SI2) stricture index (SI = anastomosis diameter/upper pouch diameter). RESULTS: Of 185 patients operated for EA/TEF in the 10-year period, 169 patients met the inclusion criteria. Primary anastomosis was performed in 130 patients and delayed anastomosis in 39 patients. Stricture formed in 55 patients (33%) within 1 year from anastomosis. Four risk factors showed strong association with stricture formation in unadjusted models: long gap (p = 0.007), delayed anastomosis (p = 0.042), SI1 (p = 0.013) and SI2 (p < 0.001). A multivariate analysis showed SI1 as significantly predictive of stricture formation (p = 0.035). Cut-off values using a receiver operating characteristic (ROC) curve were 0.275 for SI1 and 0.390 for SI2. The area under the ROC curve demonstrated increasing predictiveness from SI1 (AUC 0.641) to SI2 (AUC 0.877). CONCLUSIONS: This study identified an association between long gap and delayed anastomosis with stricture formation. Early and late stricture indices were predictive of stricture formation.

MRI Characteristics of Pediatric Renal Tumors: A SIOP-RTSG Radiology Panel Delphi Study.

BACKGROUND: The SIOP-Renal Tumor Study Group (RTSG) does not advocate invasive procedures to determine histology before the start of therapy. This may induce misdiagnosis-based treatment initiation, but only for a relatively small percentage of approximately 10% of non-Wilms tumors (non-WTs). MRI could be useful for reducing misdiagnosis, but there is no global consensus on differentiating characteristics. PURPOSE: To identify MRI characteristics that may be used for discrimination of newly diagnosed pediatric renal tumors. STUDY TYPE: Consensus process using a Delphi method. POPULATION: Not applicable. FIELD STRENGTH/SEQUENCE: Abdominal MRI including T1- and T2-weighted imaging, contrast-enhanced MRI, and diffusion-weighted imaging at 1.5 or 3 T. ASSESSMENT: Twenty-three radiologists from the SIOP-RTSG radiology panel with ≥5 years of experience in MRI of pediatric renal tumors and/or who had assessed ≥50 MRI scans of pediatric renal tumors in the past 5 years identified potentially discriminatory characteristics in the first questionnaire. These characteristics were scored in the subsequent second round, consisting of 5-point Likert scales, ranking- and multiple choice questions. STATISTICAL TESTS: The cut-off value for consensus and agreement among the majority was ≥75% and ≥60%, respectively, with a median of ≥4 on the Likert scale. RESULTS: Consensus on specific characteristics mainly concerned the discrimination between WTs and non-WTs, and WTs and nephrogenic rest(s) (NR)/nephroblastomatosis. The presence of bilateral lesions (75.0%) and NR/nephroblastomatosis (65.0%) were MRI characteristics indicated as specific for the diagnosis of a WT, and 91.3% of the participants agreed that MRI is useful to distinguish NR/nephroblastomatosis from WT. Furthermore, all participants agreed that age influenced their prediction in the discrimination of pediatric renal tumors. DATA CONCLUSION: Although the discrimination of pediatric renal tumors based on MRI remains challenging, this study identified some specific characteristics for tumor subtypes, based on the shared opinion of experts. These results may guide future validation studies and innovative efforts. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage: 3.

Fetal magnetic resonance imaging at 3 Tesla - the European experience.

BACKGROUND: The Fetal Imaging Taskforce was established in 2018 by the European Society of Paediatric Radiology. The first survey on European practice of fetal imaging published in 2020 revealed that 30% of fetal magnetic resonance imaging (MRI) is performed at 3 tesla (T). The purpose of this second survey was to identify the impact of 3-T fetal MRI with an emphasis on image quality, diagnostic yield, and technical challenges and artifacts at higher field strengths. OBJECTIVE: To describe the prenatal imaging practice at 3-T MRI units in various centres in Europe and to prepare recommendations on behalf of the Fetal Imaging Taskforce. MATERIALS AND METHODS: A survey was sent to all members performing 3-T fetal MRI. Questions included practitioner experience, magnet brand, protocols, counselling, artifacts and benefits of imaging at higher field strengths. RESULTS: Twenty-seven centres replied and reported improved spatial resolution and improved signal-to-noise ratio when performing fetal MRI at 3 T. Shading and banding artifacts and susceptibility to motion artifacts were common problems identified by practitioners at the higher field strength. For all neurological indications, practitioners reported a benefit of imaging at 3 T, most marked for posterior fossa evaluation and parenchymal lesions. CONCLUSION: The use of 3-T magnets in fetal MRI has improved the availability and quality of advanced imaging sequences and allowed for better anatomical evaluation. There remain significant challenges to minimize the impact of artifacts on image quality. This paper includes guidelines for clinical practice and imaging at 3 T.

Survival and functional outcomes in paediatric thalamic and thalamopeduncular low grade gliomas.

BACKGROUND: Childhood thalamopeduncular gliomas arise at the interface of the thalamus and cerebral peduncle. The optimal treatment is total resection but not at the cost of neurological function. We present long-term clinical and oncological outcomes of maximal safe resection. METHODS: Retrospective review of prospectively collected data: demography, symptomatology, imaging, extent of resection, surgical complications, histology, functional and oncological outcome. RESULTS: During 16-year period (2005-2020), 21 patients were treated at our institution. These were 13 girls and 8 boys (mean age 7.6 years). Presentation included progressive hemiparesis in 9 patients, raised intracranial pressure in 9 patients and cerebellar symptomatology in 3 patients. The tumour was confined to the thalamus in 6 cases. Extent of resection was judged on postoperative imaging as total (6), near-total (6) and less extensive (9). Surgical complications included progression of baseline neurological status in 6 patients, and 5 of these gradually improved to preoperative status. All tumours were classified as low-grade gliomas. Disease progression was observed in 9 patients (median progression-free survival 7.3 years). At last follow-up (median 6.1 years), all patients were alive, median Lansky score of 90. Seven patients were without evidence of disease, 6 had stable disease, 7 stable following progression and 1 had progressive disease managed expectantly. CONCLUSION: Paediatric patients with low-grade thalamopeduncular gliomas have excellent long-term functional and oncological outcomes when gross total resection is not achievable. Surgery should aim at total resection; however, neurological function should not be endangered due to excellent chance for long-term survival.

An unusual fusion gene EML4-ALK in a patient with congenital mesoblastic nephroma.

Congenital mesoblastic nephroma (CMN), the most common renal tumor of infancy, is a mesenchymal neoplasm histologically classified into classic, cellular, or mixed types. Most cellular CMNs harbor a characteristic ETV6-NTRK3 fusion. Here, we report an unusual congenital mesoblastic nephroma presenting in a newborn boy with a novel EML4-ALK gene fusion revealed by Anchored Multiplex RNA Sequencing Assay. The EML4-ALK gene fusion expands the genetic spectrum implicated in the pathogenesis of congenital mesoblastic nephroma, with yet another example of kinase oncogenic activation through chromosomal rearrangement. The methylation profile of the tumor corresponds with infantile fibrosarcoma showing the biological similarity of these two entities.

Methylation pattern in the diagnosis and prognosis of brain cancer.

Examination of changes in the methylation profile of DNA in cancer is currently used to determine the diagnosis or prognostic and predictive biomarkers. It complements histological or molecular biological examinations. At the same time, it helps to identify new diagnostic groups and subgroups. Currently, this diagnosis is most common in brain tumors, where it has become a routine examination. The established methylation profile may help even where the diagnosis or subgroup classification of the disease cannot be determined in any other way, as is the case with medulloblastoma.

Whole-body magnetic resonance imaging in pediatric oncology - recommendations by the Oncology Task Force of the ESPR.

The purpose of this recommendation of the Oncology Task Force of the European Society of Paediatric Radiology (ESPR) is to indicate reasonable applications of whole-body MRI in children with cancer and to address useful protocols to optimize workflow and diagnostic performance. Whole-body MRI as a radiation-free modality has been increasingly performed over the last two decades, and newer applications, as in screening of children with germ-line mutation cancer-related gene defects, are now widely accepted. We aim to provide a comprehensive outline of the diagnostic value for use in daily practice. Based on the results of our task force session in 2018 and the revision in 2019 during the ESPR meeting, we summarized our group's experiences in whole-body MRI. The lack of large evidence by clinical studies is challenging when focusing on a balanced view regarding the impact of whole-body MRI in pediatric oncology. Therefore, the final version of this recommendation was supported by the members of Oncology Task Force.

Gastric tumors in children: single-center study with emphasis on treatment of repeated recurrence.

PURPOSE: Analysis of surgical management and survival of pediatric patients with gastric tumors treated at our institution. METHODS: A retrospective study of patients with primary gastric tumors treated between 1993 and 2018 was conducted. RESULTS: Eight patients, five girls and three boys, were diagnosed with gastric tumors at an average age of 10.4 years (1 day-15.4 years). Surgical management included Billroth type I procedure in five and tumor excision in three patients. Histology revealed gastrointestinal stromal tumor (GIST) in four patients and one of each of schwannoma, myofibroblastic tumor, hamartoma and teratoma. Microscopically clear margins were reported in six patients. Repeated local recurrence occurred in three patients (2 × GIST, 1 × myofibroblastic tumors) who consequently underwent three, four and six reoperations. One of these patients had liver metastases, which were managed with ligation of the hepatic arteries. This patient was also diagnosed with a lung hamartoma, which was treated with a lobectomy. Survival rate was 100% with a median follow-up of 8.6 years (7 months-25.5 years). CONCLUSIONS: Gastric tumors are rare in children and represent a management challenge. Repeated recurrence of GISTs and myofibroblastic tumors remains frequent even after complete resection and may necessitate multiple surgeries, therefore patients require a lifelong follow-up.

Indications and outcomes of duodenum-preserving resection of the pancreatic head in children.

AIM OF STUDY: Duodenum-preserving resection of the pancreatic head (DPRPH) with Roux-en-Y pancreatojejunostomy is a procedure used to remove focal pathological lesions of the pancreatic head. Although predominantly used in adult patients, it is both safe and effective in children. The aim of this study was to review our experience with this procedure, with focus on its indications, complications and long-term outcomes. METHODS: A retrospective analysis of pediatric patients who underwent DPRPH between 1994 and 2015 was performed. Patient files were reviewed for demographic, diagnostic, operative and histological details, postoperative complications. Patients were contacted telephonically and sent questionnaires to determine long-term outcomes. RESULTS: The study cohort consists of 21 patients, 14 girls and 7 boys, with an average age of 11.72 years (range 3 months to 18.6 years), who underwent DPRPH with end-to-end anastomosis of the jejunum to the pancreatic body (Roux-en-Y anastomosis). In four cases the head and also part of the body of the pancreas was resected. In the remaining 17 cases, only the head of the pancreas was resected. Indications for DPRPH were solid pseudopapillary tumor of the pancreas (n = 10), trauma (n = 8), pancreas divisum (n = 1), focal congenital hyperinsulinism (n = 1) and pancreatic cyst (n = 1). The length of follow-up ranged from 1 to 22 years (average 9.66). One patient developed a biliary fistula, which closed spontaneously within 2 weeks after stent insertion. A recurrence of abdominal pain was reported in two patients, occurring at 7 months after the operation in one patient and at 1 year in the other. Pancreatic endocrine insufficiency did not occur in any of the 21 patients. Seven patients currently require a low fat diet, five of which need pancreatic enzyme supplementation. An additional two patients need enzyme supplementation without dietary restriction. CONCLUSION: DPRPH is a safe and effective procedure for the treatment of large focal pathological lesions of the pancreatic head in children. As a less invasive procedure than pancreatoduodenectomy, it is more appropriate for the developing child.

Prenatally Acquired Multiple Limb Ischemia in a Very Low Birth Weight Monochorionic Twin.

Limb ischemia is an extremely rare event occuring in monochorionic twin pregnancy complicated by twin-to-twin transfusion syndrome (TTTS) and twin anemia polycythemia sequence (TAPS). The authors describe a case of TTTS and TAPS treated successfully using amnioreduction and laser ablation. However, severe ischemia of both lower extremities in the recipient twin developed after the fetal treatment. This serious complication was diagnosed on MRI in utero and confirmed postnatally. Elective amputation of the affected limbs was performed. The etiology of the disease remains unclear despite profound clinical and histopathological examinations; although the role of thromboembolism in monochorionic pregnancy seems to be most likely, this unique case of multiple limb ischemia with distinct macroscopic findings has not yet been described.

Peri-ictal headache due to epileptiform activity in a disconnected hemisphere.

A 4-year-old girl with intractable epilepsy due to left-side hemispheric cortical dysplasia underwent a hemispherotomy. She was seizure-free after the surgery. EEG showed persistent abundant epileptiform activity over the left (disconnected) hemisphere, including ictal patterns that neither generalised nor had clinical correlates. Antiepileptic medication was completely withdrawn four years following the surgery. One week after the withdrawal, she developed episodes of intense left-sided hemicranias (ipsilateral to the surgery) with vomiting and photophobia that did not resemble her habitual seizures and were unresponsive to non-steroidal anti-inflammatory drugs. Video-EEG showed association of the headache attacks with ictal patterns over the disconnected hemisphere. Brain MRI revealed increased signal changes in the left hemisphere. Attacks responded promptly to i.v. midazolam and carbamazepine at a low dose. Mechanisms underlying peri-ictal headache originating in the disconnected hemisphere are discussed. [Published with video sequences].

Optic Nerve Hypoplasia - Case Report.

The case report of a young myope (born in 1997) who was diagnosed with bilateral concentric narrowing of the visual field to 15-20 degrees in 2021 is presented. On eye fundus, the findings were normal with central excavation c/d=0.5 and 0.4, respectively. OCT showed loss of retinal nerve fiber layer - in both vertical quadrants, including a reduction in the ganglion cell complex. Electrophysiological examination (PERG) showed normal retinal responses. Visual evoked responses (PVEP) after stimulation squared a 1 degree decrease in amplitudes, with no prolongation of P100 latency. When stimulated with 15-minute squares, responses were normal (see Supplementary Figure). Magnetic resonance imaging of the brain showed a narrowing of the chiasm. In conclusion, optic chiasm hypoplasia may not always have distinct morphological and functional manifestations. In addition to imaging methods, electrophysiological examination of the visual analyser was of great help for its verification.

A 5-year-old boy with super-refractory status epilepticus and RANBP2 variant warranting life-saving hemispherotomy.

Focal cortical dysplasia (FCD) represents the most common cause of drug-resistant epilepsy in adult and pediatric surgical series. However, genetic factors contributing to severe phenotypes of FCD remain unknown. We present a patient with an exceptionally rapid development of drug-resistant epilepsy evolving in super-refractory status epilepticus. We performed multiple clinical (serial EEG, MRI), biochemical (metabolic and immunological screening), genetic (WES from blood- and brain-derived DNA), and histopathological investigations. The patient presented 1 month after an uncomplicated varicella infection. MRI was negative, as well as other biochemical and immunological examinations. Whole-exome sequencing of blood-derived DNA detected a heterozygous paternally inherited variant NM_006267.4(RANBP2):c.5233A>G p.(Ile1745Val) (Chr2[GRCh37]:g.109382228A>G), a gene associated with a susceptibility to infection-induced acute necrotizing encephalopathy. No combination of anti-seizure medication led to a sustained seizure freedom and the patient warranted induction of propofol anesthesia with high-dose intravenous midazolam and continuous respiratory support that however failed to abort seizure activity. Brain biopsy revealed FCD type IIa; this finding led to the indication of an emergency right-sided hemispherotomy that rendered the patient temporarily seizure-free. Postsurgically, he remains on antiseizure medication and experiences rare nondisabling seizures. This report highlights a uniquely severe clinical course of FCD putatively modified by the RANBP2 variant. PLAIN LANGUAGE SUMMARY: We report a case summary of a patient who came to our attention for epilepsy that could not be controlled with medication. His clinical course progressed rapidly to life-threatening status epilepticus with other unusual neurological findings. Therefore, we decided to surgically remove a piece of brain tissue in order to clarify the diagnosis that showed features of a structural brain abnormality associated with severe epilepsy, the focal cortical dysplasia. Later, a genetic variant in a gene associated with another condition, was found, and we hypothesize that this genetic variant could have contributed to this severe clinical course of our patient.

Clinical and molecular study of radiation-induced gliomas.

In this study, we provide a comprehensive clinical and molecular biological characterization of radiation-induced gliomas (RIG), including a risk assessment for developing gliomas. A cohort of 12 patients who developed RIG 9.5 years (3-31 years) after previous cranial radiotherapy for brain tumors or T-cell acute lymphoblastic leukemia was established. The derived risk of RIG development based on our consecutive cohort of 371 irradiated patients was 1.6% at 10 years and 3.02% at 15 years. Patients with RIG glioma had a dismal prognosis with a median survival of 7.3 months. We described radiology features that might indicate the suspicion of RIG rather than the primary tumor recurrence. Typical molecular features identified by molecular biology examination included the absence of Histon3 mutation, methylation profile of pedHGG-RTK1 and the presence of recurrent PDGFRA amplification and CDKN2A/B deletion. Of the two long-term surviving patients, one had gliomatosis cerebri, and the other had pleomorphic xanthoastrocytoma with BRAF V600E mutation. In summary, our experience highlights the need for tissue diagnostics to allow detailed molecular biological characterization of the tumor, differentiation of the secondary tumor from the recurrence of the primary disease and potentially finding a therapeutic target.

Predictors of seizure-free outcome after epilepsy surgery for pediatric tuberous sclerosis complex.

PURPOSE: Variable predictors of postsurgical seizure outcome have been reported in children with tuberous sclerosis complex (TSC). We analyzed a large surgical series of pediatric TSC patients in order to identify prognostic factors crucial for selection of subjects for epilepsy surgery. METHODS: Thirty-three children with TSC who underwent excisional epilepsy surgery at Miami Children's Hospital were retrospectively reviewed. A total of 29 clinical, neuropsychological, electroencephalography (EEG), magnetic resonance imaging (MRI), and surgical variables were analyzed and related to seizure outcomes. Univariate Barnard's exact test, Wilcoxon's rank-sum test, and multivariate statistical Cox's model were used to examine the significance of associations between the variables and seizure outcome. KEY FINDINGS: Eighteen patients (55%) have been seizure-free 2 years after (final) surgery; postoperative complications occurred in five subjects (15%). Complete removal of epileptogenic tissue detected by both MRI and intracranial EEG, regional scalp interictal EEG patterns, and agreement of interictal and ictal EEG localization were the most powerful predictors of seizure-free outcome. Other significant predictors included occurrence of regional scalp ictal EEG patterns, fewer brain regions affected by tubers, presence of preoperative hemiparesis, and one-stage surgery. Remaining factors such as age at seizure onset, incidence of infantile spasms or other seizure types, duration of epilepsy, seizure frequency, mental retardation, as well as types and extent of resections did not influence outcome. SIGNIFICANCE: Perioperative features rather than preoperative variables are the most important determinants of postsurgical seizure outcome in patients with TSC. Our findings may assist in the surgical management of these patients.