Risk factors for domain-specific neurocognitive outcome in pediatric survivors of a brain tumor in the posterior fossa - Results of the HIT 2000 trial.

BACKGROUND: Neurocognition can be severely affected in pediatric brain tumor survivors. We analyzed the association of cognitive functioning with radiotherapy dose, postoperative cerebellar mutism syndrome (pCMS), hydrocephalus, intraventricular methotrexate (MTX) application, tumor localization and biology in pediatric survivors of a posterior fossa tumor. METHODS: Subdomain-specific neurocognitive outcome data from 279 relapse-free survivors of the HIT-2000 trial (241 medulloblastoma and 38 infratentorial ependymoma) using the Neuropsychological Basic Diagnostic (NBD) tool based on Cattell-Horn-Carroll's model for intelligence were analyzed. RESULTS: Cognitive performance 5.14 years (mean; range=1.52-13.02) after diagnosis was significantly below normal for all subtests. Processing speed and psychomotor abilities were most affected. Influencing factors were domain-specific: CSI-dose had strong impact on most subtests. pCMS was associated with psychomotor abilities (ß=-0.25 to -0.16) and processing speed (ß=-0.32). Postoperative hydrocephalus correlated with crystallized intelligence (ß=-0.20) and short-term memory (ß=-0.15), age with crystallized intelligence (ß=0.15) and psychomotor abilities (ß=-0.16 and ß=-0.17). Scores for fluid intelligence (ß=-0.23), short-term memory (ß=-0.17) and visual processing (ß=-0.25) declined, and scores for selective attention improved (ß=0.29) with time after diagnosis. CONCLUSION: Dose of CSI was strongly associated with neurocognitive outcome. Low psychomotor abilities and processing speed both in patients treated with and without CSI suggest a strong contribution of the tumor and its surgery on these functions. Future research therefore should analyze strategies to both reduce CSI-dose and toxicity caused by other treatment modalities.

Adaption of neurosurgical resection patterns for pediatric low-grade glioma spanning two decades-Report from the German LGG-studies 1996-2018.

INTRODUCTION: Neurosurgery is considered the mainstay of treatment for pediatric low-grade glioma (LGG); the extent of resection determines subsequent stratification in current treatment protocols. Yet, surgical radicality must be balanced against the risks of complications that may affect long-term quality of life. We investigated whether this consideration impacted surgical resection patterns over time for patients of the German LGG studies. PATIENTS AND METHODS: Four thousand two hundred and seventy pediatric patients from three successive LGG studies (median age at diagnosis 7.6 years, neurofibromatosis (NF1) 14.7%) were grouped into 5 consecutive time intervals (TI1-5) for date of diagnosis and analyzed for timing and extent of first surgery with respect to tumor site, histology, NF1-status, sex, and age. RESULTS: The fraction of radiological LGG diagnoses increased over time (TI1 12.6%; TI5 21.7%), while the extent of the first neurosurgical intervention (3440/4270) showed a reduced fraction of complete/subtotal and an increase of partial resections from TI1 to TI5. Binary logistic regression analysis for the first intervention within the first year following diagnosis confirmed the temporal trends (p < 0.001) and the link with tumor site for each extent of resection (p < 0.001). Higher age is related to more complete resections in the cerebellum and cerebral hemispheres. CONCLUSIONS: The declining extent of surgical resections over time was unrelated to patient characteristics. It paralleled the evolution of comprehensive treatment algorithms; thus, it may reflect alignment of surgical practice to recommendations in respect to age, tumor site, and NF1-status integrated as such into current treatment guidelines. Further investigations are needed to understand how planning, performance, or tumor characteristics impact achieving surgical goals.

Surgical options of chiasmatic hypothalamic glioma-a relevant part of therapy in an interdisciplinary approach for tumor control.

OBJECTIVE: The extent of resection of pediatric low-grade glioma mostly improves progression-free survival. In chiasmatic hypothalamic glioma (CHG), complete resections are limited due to the relevantly high risk of associated neurological and endocrinological deficits. Still, surgery might have its role in the framework of a multidisciplinary team (MDT) approach. We report our retrospective experience from two centers on surgical options and their impact on long-term outcomes. METHODS: Medical records of surgically treated pediatric CHG patients between 2004 and 2022 were analyzed. Patient characteristics, surgical interventions, histology, and non-surgical therapy were retrieved together with outcome measures such as visual acuity, endocrine function, and survival. RESULTS: A total of 63 patients (33 female, NF-1, n = 8) were included. Age at first diagnosis was 4.6 years (range 0.2-16.9) and cohort follow-up was 108 ± 72 months. Twenty patients were surgically treated with a biopsy and 43 patients with debulking at a median age of 6.5 years (range 0.16-16.9). Patients received a median of 2 tumor surgeries (range 1-5). Cyst drainage was accomplished in 15 patients, and 27 patients had ventriculoperitoneal shunt implantation. Non-surgical therapy was given in 69.8%. At the end of follow-up, 74.6% of patients had stable disease. The cohort had a median Karnofsky score of 90 (range 0-100). Four patients died. Hormone substitution was necessary in 30.2%, and visual acuity was impaired in 66% of patients. CONCLUSION: Pediatric CHG is a chronic disease due to overall high survival with multiple progressions. Surgical therapy remains a key treatment option offering biopsy, limited tumor-debulking, cyst fenestration, and hydrocephalus management in the framework of MDT decision-making. Team experience contributes to reducing possible deficits in this challenging cohort.

Rapid DNA methylation-based classification of pediatric brain tumors from ultrasonic aspirate specimens.

BACKGROUND: Although cavitating ultrasonic aspirators are commonly used in neurosurgical procedures, the suitability of ultrasonic aspirator-derived tumor material for diagnostic procedures is still controversial. Here, we explore the feasibility of using ultrasonic aspirator-resected tumor tissue to classify otherwise discarded sample material by fast DNA methylation-based analysis using low pass nanopore whole genome sequencing. METHODS: Ultrasonic aspirator-derived specimens from pediatric patients undergoing brain tumor resection were subjected to low-pass nanopore whole genome sequencing. DNA methylation-based classification using a neural network classifier and copy number variation analysis were performed. Tumor purity was estimated from copy number profiles. Results were compared to microarray (EPIC)-based routine neuropathological histomorphological and molecular evaluation. RESULTS: 19 samples with confirmed neuropathological diagnosis were evaluated. All samples were successfully sequenced and passed quality control for further analysis. DNA and sequencing characteristics from ultrasonic aspirator-derived specimens were comparable to routinely processed tumor tissue. Classification of both methods was concordant regarding methylation class in 17/19 (89%) cases. Application of a platform-specific threshold for nanopore-based classification ensured a specificity of 100%, whereas sensitivity was 79%. Copy number variation profiles were generated for all cases and matched EPIC results in 18/19 (95%) samples, even allowing the identification of diagnostically or therapeutically relevant genomic alterations. CONCLUSION: Methylation-based classification of pediatric CNS tumors based on ultrasonic aspirator-reduced and otherwise discarded tissue is feasible using time- and cost-efficient nanopore sequencing.

Experience in endoscope choice for neuroendoscopic lavage for intraventricular hemorrhage of prematurity: a systematic review.

OBJECTIVE: Intraventricular hemorrhage (IVH) of prematurity occurs in 20-38% of infants born < 28 weeks gestational age and 15% of infants born in 28-32 weeks gestational age. Treatment has evolved from conservative management and CSF diversion of temporizing and shunting procedures to include strategies aimed at primarily clearing intraventricular blood products. Neuroendoscopic lavage (NEL) aims to decrease the intraventricular blood burden under the same anesthetic as temporizing CSF diversion measures in cases of hydrocephalus from IVH of prematurity. Given the variety of neuroendoscopes, we sought to review the literature and practical considerations to help guide neuroendoscope selection when planning NEL. METHODS: We conducted a systematic review of the literature on neuroendoscopic lavage in IVH of prematurity to examine data on the choice of neuroendoscope and outcomes regarding shunt rate. We then collected manufacturer data on neuroendoscopic devices, including inflow and outflow mechanisms, working channel specifications, and tools compatible with the working channel. We paired this information with the advantages and disadvantages reported in the literature and observations from the experiences of pediatric neurosurgeons from several institutions to provide a pragmatic evaluation of international clinical experience with each neuroendoscope in NEL. RESULTS: Eight studies were identified; four neuroendoscopes have been used for NEL as reported in the literature. These include the Karl Storz Flexible Neuroendoscope, LOTTA® system, GAAB system, and Aesculap MINOP® system. The LOTTA® and MINOP® systems were similar in setup and instrument options. Positive neuroendoscope features for NEL include increased degrees of visualization, better visualization with the evolution of light and camera sources, the ability to sterilize with autoclave processes, balanced inflow and outflow mechanisms via separate channels, and a working channel. Neuroendoscope disadvantages for NEL may include special sterilization requirements, large outer diameter, and limitations in working channels. CONCLUSIONS: A neuroendoscope integrating continuous irrigation, characterized by measured inflow and outflow via separate channels and multiple associated instruments, appears to be the most commonly used technology in the literature. As neuroendoscopes evolve, maximizing clear visualization, adequate inflow, measured outflow, and large enough working channels for paired instrumentation while minimizing the footprint of the outer diameter will be most advantageous when applied for NEL in premature infants.

Analysis of bihemispheric language function in pediatric neurosurgical patients using repetitive navigated transcranial magnetic stimulation.

OBJECTIVE: Language dominance in the developing brain can vary widely across anatomical and pathological conditions as well as age groups. Repetitive navigated transcranial magnetic stimulation (rnTMS) has been applied to calculate the hemispheric dominance ratio (HDR) in adults. In this study, the authors aimed to assess the feasibility of using rnTMS to identify language lateralization in a pediatric neurosurgical cohort and to correlate the preoperative rnTMS findings with the postoperative language outcome. METHODS: A consecutive prospectively collected cohort of 19 children with language-associated lesions underwent bihemispheric rnTMS mapping prior to surgery (100 stimulation sites on each hemisphere). In addition to feasibility and adverse effects, the HDR (ratio of the left hemisphere to right hemisphere error rate) was calculated. The anatomical surgical site and postoperative language outcome at 3 months after surgery were assessed according to clinical documentation. RESULTS: Repetitive nTMS mapping was feasible in all 19 children (mean age 12.5 years, range 4-17 years; 16 left-sided lesions) without any relevant adverse events. Thirteen children (68%) showed left hemispheric dominance (HDR > 1.1), and 2 children (11%) showed right hemispheric dominance (HDR < 0.9). In 4 children (21%), the bihemispheric error rates were nearly the same (HDR ≥ 0.9 and ≤ 1.1). Sixteen children underwent surgery (14 tumor/lesion resections and 2 hemispherotomies) and 3 patients continued conservative therapy. After surgery, 4 patients (25%) showed an improvement in language function, 10 (63%) presented with stable language function, and 2 (12.5%) experienced deterioration in language function. Of the 6 patients with right hemispheric language involvement, 4 (80%) had glial tumors, 1 (20%) had focal cortical dysplasia, and 1 (20%) experienced hypoxic brain injury. Children with right hemispheric language involvement (HDR ≤ 1.1) did not show any language deterioration postoperatively. CONCLUSIONS: Bihemispheric rnTMS language mapping as a noninvasive mapping technique to assess lateralization of language function in the pediatric neurosurgical population is safe and feasible. Why relevant right hemispheric language function (HDR ≤ 1.1) was associated with postoperative unaltered language function needs to be validated in future studies. Bihemispheric rnTMS language mapping strengthens risk-benefit considerations prior to pediatric tumor/epilepsy surgery in language-associated areas.

Navigated bedside implantation of external ventricular drains with mobile health guidance: technical note and case series.

PURPOSE: External ventricular drain (EVD) implantation is one of the fundamental procedures of emergency neurosurgery usually performed freehand at bedside or in the operating room using anatomical landmarks. However, this technique is frequently associated with malpositioning leading to complications or dysfunction. Here, we describe a novel navigated bedside EVD insertion technique, which is evaluated in a clinical case series with the aim of safety, accuracy, and efficiency in neurosurgical emergency settings. METHODS: From 2021 to 2022, a mobile health-assisted navigation instrument (Thomale Guide, Christoph Miethke, Potsdam, Germany) was used alongside a battery-powered single-use drill (Phasor Health, Houston, USA) for bedside EVD placement in representative neurosurgical pathologies in emergency situations requiring ventricular cerebrospinal fluid (CSF) relief and intracranial pressure (ICP) monitoring. RESULTS: In all 12 patients (8 female and 4 male), navigated bedside EVDs were placed around the foramen of Monro at the first ventriculostomy attempt. The most frequent indication was aneurysmal subarachnoid hemorrhage. Mean operating time was 25.8 ± 15.0 min. None of the EVDs had to be revised due to malpositioning or dysfunction. Two EVDs were converted into a ventriculoperitoneal shunt. Drainage volume was 41.3 ± 37.1 ml per day in mean. Mean length of stay of an EVD was 6.25 ± 2.8 days. Complications included one postoperative subdural hematoma and cerebrospinal fluid infection, respectively. CONCLUSION: Combining a mobile health-assisted navigation instrument with a battery-powered drill and an appropriate ventricular catheter may enable and enhance safety, accuracy, and efficiency in bedside EVD implantation in various pathologies of emergency neurosurgery without adding relevant efforts.

Tailored Concept for Accurate Neuroendoscopy: A Comparative Retrospective Single-Center Study on Image-Guided Neuroendoscopic Procedures.

OBJECTIVE: Precise planning and execution is key for neuroendoscopic interventions, which can be based on different available aiding technologies. The aim of this retrospective study is to report a case-based use of guided neuroendoscopy and to develop a stratification algorithm for the available technologies. METHODS: We reviewed consecutive neuroendoscopic cases performed at our center from 2016 to 2018. We distinguished between patients receiving a new burr hole (group A) and those with a preexisting burr hole (group B). Case-specific technical requirements for procedure planning and execution, complication rate, surgical outcome, and possible subsequent surgery were evaluated. From this experience, a stratification system was developed to tailor the available guiding technologies. RESULTS: A total of 309 neuroendoscopic interventions in 243 patients were included in the present study. The cases included hydrocephalic (81.6%) and nonhydrocephalic (18.4%) conditions. The interventions were supported by coordinate-based (group A, n = 49; group B, n = 67), guide-based (group A, n = 42; group B, n = 0), ultrasound-guided (group A, n = 50; group B, n = 7), or navigated augmented reality-guided (group A, n = 85; group B, n = 9) techniques. The overall complication rate was 4.5%. Stratified by the surgical indication, fontanel status, entry point localization, presence of a preexisting burr hole, ventricular size, and number of targets, an approach toward image-guided neuroendoscopy is suggested. CONCLUSIONS: Planning and technical guidance is essential in neuroendoscopic procedures. The stratified decision-making algorithm for different available technologies aims to achieve lower cost and time consumption, which was found to be safe and efficient. Further investigations are warranted to deliver solid data on procedure efficiency.

The importance of routine genetic testing in pediatric epilepsy surgery.

Genetic variants in relevant genes coexisting with MRI lesions in children with drug-resistant epilepsy (DRE) can negatively influence epilepsy surgery outcomes. Still, presurgical evaluation does not include genetic diagnostics routinely. Here, we report our presurgical evaluation algorithm that includes routine genetic testing. We analyzed retrospectively the data of 68 children with DRE operated at a mean age of 7.8 years (IQR: 8.1 years) at our center. In 49 children, genetic test results were available. We identified 21 gene variants (ACMG III: n = 7, ACMG IV: n = 2, ACMG V: n = 12) in 19 patients (45.2%) in the genes TSC1, TSC2, MECP2, DEPDC5, HUWE1, GRIN1, ASH1I, TRIO, KIF5C, CDON, ANKD11, TGFBR2, ATN1, COL4A1, JAK2, KCNQ2, ATP1A2, and GLI3 by whole-exome sequencing as well as deletions and duplications by array CGH in six patients. While the results did not change the surgery indication, they supported counseling with respect to postoperative chance of seizure freedom and weaning of antiseizure medication (ASM). The presence of genetic findings leads to the postoperative retention of at least one ASM. In our cohort, the International League against Epilepsy (ILAE) seizure outcome did not differ between patients with and without abnormal genetic findings. However, in the 7/68 patients with an unsatisfactory ILAE seizure outcome IV or V 12 months postsurgery, 2 had an abnormal or suspicious genetic finding as a putative explanation for persisting seizures postsurgery, and 3 had received palliative surgery including one TSC patient. This study highlights the importance of genetic testing in children with DRE to address putative underlying germline variants as genetic epilepsy causes or predisposing factors that guide patient and/or parent counseling on a case-by-case with respect to their individual chance of postoperative seizure freedom and ASM weaning. PLAIN LANGUAGE SUMMARY: Genetic variants in children with drug-resistant epilepsy (DRE) can negatively influence epilepsy surgery outcomes. However, presurgical evaluation does not include genetic diagnostics routinely. This retrospective study analyzed the genetic testing results of the 68 pediatric patients who received epilepsy surgery in our center. We identified 21 gene variants by whole-exome sequencing as well as deletions and duplications by array CGH in 6 patients. These results highlight the importance of genetic testing in children with DRE to guide patient and/or parent counseling on a case-by-case with respect to their individual chance of postoperative seizure freedom and ASM weaning.

A European multicenter outcome study on the different perioperative airway management policies following midface surgery in syndromic craniosynostosis: a proposal for a Standard Operating Procedure.

BACKGROUND: Perioperative airway management following midface advancements in children with Apert and Crouzon/Pfeiffer syndrome can be challenging, and protocols often differ. This study examined airway management following midface advancements and postoperative respiratory complications. METHODS: A multicenter, retrospective cohort study was performed to obtain information about the timing of extubation, perioperative airway management, and respiratory complications after monobloc / le Fort III procedures. RESULTS: Ultimately, 275 patients (129 monobloc and 146 Le Fort III) were included; 62 received immediate extubation and 162 delayed extubation; 42 had long-term tracheostomies and nine perioperative short-term tracheostomies. Short-term tracheostomies were in most centers reserved for selected cases. Patients with delayed extubation remained intubated for three days (IQR 2 - 5). The rate of no or only oxygen support after extubation was comparable between patients with immediate and delayed extubation, 58/62 (94%) and 137/162 (85%) patients, respectively. However, patients with immediate extubation developed less postoperative pneumonia than those with delayed, 0/62 (0%) versus 24/161 (15%) (P = 0.001), respectively. Immediate extubation also appeared safe in moderate/severe OSA since 19/20 (95%) required either no or only oxygen support after extubation. The odds of developing intubation-related complications increased by 21% with every extra day of intubation. CONCLUSIONS: Immediate extubation following midface advancements was found to be a safe option, as it was not associated with respiratory insufficiency but did lead to fewer complications. Immediate extubation should be considered routine management in patients with no/mild OSA and should be the aim in moderate/severe OSA after careful assessment.

The Supraorbital Eyebrow Approach in Pediatric Neurosurgery: Perspectives and Challenges of Frontal Keyhole Surgery.

OBJECT: Supraorbital craniotomy via an eyebrow incision provides minimally invasive cosmetically favorable access to both orbital and intracranial pathologies. We describe the indication, surgical technique, and clinical course using this surgical approach in a cohort of patients from a single pediatric neurosurgery unit. METHODS: In a retrospective analysis, we identified all surgical cases between January 2013 and April 2022 who underwent the supraorbital craniotomy via an eyebrow incision. Craniotomy was performed using piezosurgery ultrasonic bone incision. An interdisciplinary team of an orbital surgeon and a neurosurgeon performed the orbital surgeries. Clinical and surgical characteristics, perioperative data, possible complications, or redo surgeries as well as ophthalmologic status were assessed. RESULTS: Clinical data of 37 interventions (cases) in 30 patients (age: 8 ± 6.5 years) were analyzed. The supraorbital craniotomy established access to the cranial, lateral, and central portions of the orbit (n = 11) and ipsilateral fronto-medial portions of the skull base (n = 26). Thirty cases suffered from tumor disease with heterogeneous histopathologic diagnoses, and in 13 cases, adjuvant therapy was required. The mean duration of surgery was 163 ± 95 min, and the mean time of hospital stay was 6.0 ± 2.8 days. In two cases (5.4%), the following complications were observed. One infection treated by puncture and antibiotics and one revision surgery was necessary due to loosening of osteosynthesis material. Postoperative visual function was stable compared to preoperative status after all interventions. After a mean follow-up time of 26 ± 25.9 months for oncologic cases the long term outcome was complete remission in 13, stable disease in 14, progressive disease in 1 and death in 2 patients. CONCLUSION: The supraorbital eyebrow approach is feasible and safe in pediatric neurosurgical cases as a minimally invasive and cosmetic favorable technique and should be considered for intraorbital as well as ipsilateral intracranial lesions adjacent to the skull base. Interdisciplinary cooperation enables a broader spectrum of surgical options in orbital and complex, fronto-basal, skull base pathologies.

Epilepsy surgery in early infancy: A retrospective, multicenter study.

Although epilepsy surgery is the only curative therapeutic approach for lesional drug-resistant epilepsy (DRE), there is reluctance to operate on infants due to a fear of complications. A recent meta-analysis showed that epilepsy surgery in the first 6 months of life can achieve seizure control in about two thirds of children. However, robust data on surgical complications and postoperative cognitive development are lacking. We performed a retrospective multicenter study of infants who underwent epilepsy surgery in the first 6 months of life. 15 infants underwent epilepsy surgery at a median age of 134 days (IQR: 58) at four centers. The most common cause was malformation of cortical development, and 13 patients underwent a hemispherotomy. Two thirds required intraoperative red blood transfusions. Severe intraoperative complications occurred in two patients including death in one infant due to cardiovascular insufficiency. At a median follow-up of 1.5 years (IQR: 1.8), 57% of patients were seizure-free. Three patients where reoperated at a later age, resulting in 79% seizure freedom. Anti-seizure medication could be reduced in two thirds, and all patients improved in their development. Our findings suggest that early epilepsy surgery can result in good seizure control and developmental improvement. However, given the perioperative risks, it should be performed only in specialized centers.

MAPK inhibitor sensitivity scores predict sensitivity driven by the immune infiltration in pediatric low-grade gliomas.

Pediatric low-grade gliomas (pLGG) show heterogeneous responses to MAPK inhibitors (MAPKi) in clinical trials. Thus, more complex stratification biomarkers are needed to identify patients likely to benefit from MAPKi therapy. Here, we identify MAPK-related genes enriched in MAPKi-sensitive cell lines using the GDSC dataset and apply them to calculate class-specific MAPKi sensitivity scores (MSSs) via single-sample gene set enrichment analysis. The MSSs discriminate MAPKi-sensitive and non-sensitive cells in the GDSC dataset and significantly correlate with response to MAPKi in an independent PDX dataset. The MSSs discern gliomas with varying MAPK alterations and are higher in pLGG compared to other pediatric CNS tumors. Heterogenous MSSs within pLGGs with the same MAPK alteration identify proportions of potentially sensitive patients. The MEKi MSS predicts treatment response in a small set of pLGG patients treated with trametinib. High MSSs correlate with a higher immune cell infiltration, with high expression in the microglia compartment in single-cell RNA sequencing data, while low MSSs correlate with low immune infiltration and increased neuronal score. The MSSs represent predictive tools for the stratification of pLGG patients and should be prospectively validated in clinical trials. Our data supports a role for microglia in the response to MAPKi.

Neurosurgical morbidity in pediatric supratentorial midline low-grade glioma: Results from the German LGG studies.

Surgical resection is a mainstay of treatment for pediatric low-grade glioma (LGG) within all current therapy algorithms, yet associated morbidity is scarcely reported. As supratentorial midline (SML) interventions are particularly challenging, we investigated the frequency of neurosurgical complications/new impairments aiming to identify their risk factors. Records were retrospectively analyzed from 318 patients with SML-LGG from successive German multicenter LGG studies, undergoing surgery between May 1998 and June 2020. Exactly 537 operations (230 resections, 167 biopsies, 140 nontumor procedures) were performed in 318 patients (54% male, median age: 7.6 years at diagnosis, 9.5 years at operation, 11% NF1, 42.5% optic pathway glioma). Surgical mortality rate was 0.93%. Applying the Drake classification, postoperative surgical morbidity was observed following 254/537 (47.3%) and medical morbidity following 97/537 (18.1%) patients with a 40.1% 30-day persistence rate for newly developed neurological deficits (65/162). Neuroendocrine impairment affected 53/318 patients (16.7%), visual deterioration 34/318 (10.7%). Postsurgical morbidity was associated with patient age <3 years at operation, tumor volume ≥80 cm3 , presence of hydrocephalus, complete resection, surgery in centers with less than median reported tumor-related procedures and during the earlier study period between 1998 and 2006, while the neurosurgical approach, tumor location, NF1 status or previous nonsurgical treatment were not. Neurosurgery-associated morbidity was frequent in pediatric patients with SML-LGG undergoing surgery in the German LGG-studies. We identified patient- and institution-associated factors that may increase the risk for complications. We advocate that local multidisciplinary teams consider the planned extent of resection and surgical skills.

Biopsies of Caudal Brainstem Tumors in Pediatric Patients-A Single-Center Retrospective Case Series.

OBJECTIVE: The indication for performing biopsies in patients with diffuse lesions in the brain stem is controversial. The possible risks associated with the technically challenging interventions must be balanced against clarifying the diagnosis and the possible therapeutic options. We reviewed the feasibility, risk profile, and diagnostic yield of different biopsy techniques in a pediatric cohort. METHODS: We retrospectively included all patients aged <18 years who had undergone biopsy of the caudal brainstem region (pons, medulla oblongata) at our pediatric neurosurgical center from 2009 to 2022. RESULTS: We identified 27 children. Biopsies were performed using frameless stereotactic (Varioguide; n = 12), robotic-assisted (Autoguide; n = 4), endoscopic (n = 3), and open biopsy (n = 8) techniques. Intervention-related mortality was not observed. Three patients experienced a transient postoperative neurological deficit. No patient experienced intervention-related permanent morbidity. Biopsy yielded the histopathological diagnosis in all 27 cases. Molecular analysis was feasible for 97% of the cases. The most common diagnosis was H3K27M-mutated diffuse midline glioma (60%). Low-grade gliomas were identified in 14% of patients. Overall survival was 62.5% after 24 months of follow-up. CONCLUSIONS: Biopsies of the caudal brainstem in children were feasible and safe in the presented setup. The amount of tumor material acquired allowing for an integrated diagnosis and was obtained at reasonable risk. The selection of the surgical technique depends on the tumor location and growth pattern. We recommend the performance of brainstem tumor biopsies in children at specialized centers to better understand the biology and enable possible novel therapeutic options.

[Pediatric Intracranial Ependymoma - Recommendations for First-Line Treatment from the German HIT-MED study group]. / Kinder und Jugendliche mit intrakraniellem Ependymom ­ Empfehlungen der HIT-MED-Studiengruppe der GPOH zur Erstlinientherapie.

Biological subtypes of ependymoma (EPN) have been introduced by the recent WHO classification and appear to have great impact on the clinical course, but have not yet found their way into clinical risk stratification. Further, the overall unfavorable prognosis underlines the fact that current therapeutic strategies need further evaluation for improvement. To date, there is no international consensus regarding first-line treatment for children with intracranial EPN. Extent of resection is known to be the most important clinical risk factor, leading to the consensus that consequent evaluation for re-surgery of postoperative residual tumor needs to have highest priority. Furthermore, efficacy of local irradiation is unquestioned and recommended for patients aged>1 year. In contrast, efficacy of chemotherapy is still under discussion. The European trial SIOP Ependymoma II aims at evaluating efficacy of different chemotherapy elements, leading to the recommendation to include German patients. The BIOMECA study, as biological accompanying study, aims at identifying new prognostic parameters. These results might help to develop targeted therapies for unfavorable biological subtypes. For patient who are not qualified for inclusion into the interventional strata, the HIT-MED Guidance 5.2 provides specific recommendations. This article is meant as an overview of national guidelines regarding diagnostics and treatment as well as of treatment according to the SIOP Ependymoma II trial protocol.

Multiomic neuropathology improves diagnostic accuracy in pediatric neuro-oncology.

The large diversity of central nervous system (CNS) tumor types in children and adolescents results in disparate patient outcomes and renders accurate diagnosis challenging. In this study, we prospectively integrated DNA methylation profiling and targeted gene panel sequencing with blinded neuropathological reference diagnostics for a population-based cohort of more than 1,200 newly diagnosed pediatric patients with CNS tumors, to assess their utility in routine neuropathology. We show that the multi-omic integration increased diagnostic accuracy in a substantial proportion of patients through annotation to a refining DNA methylation class (50%), detection of diagnostic or therapeutically relevant genetic alterations (47%) or identification of cancer predisposition syndromes (10%). Discrepant results by neuropathological WHO-based and DNA methylation-based classification (30%) were enriched in histological high-grade gliomas, implicating relevance for current clinical patient management in 5% of all patients. Follow-up (median 2.5 years) suggests improved survival for patients with histological high-grade gliomas displaying lower-grade molecular profiles. These results provide preliminary evidence of the utility of integrating multi-omics in neuropathology for pediatric neuro-oncology.

Family Burden and Epilepsy Surgery in Children with Drug-Resistant Epilepsy.

INTRODUCTION: Family burden (FB) in pediatric patients with drug-resistant epilepsy (DRE) is significantly higher than that in children with non-DRE. Epilepsy surgery is an established approach to treat DRE, and this study examines the impact of pediatric epilepsy surgery on FB. METHODS: We retrospectively analyzed data of families and pediatric patients with focal structural DRE treated with epilepsy surgery at our epilepsy center from April 2018 to November 2021. We examined the relationship between cognitive, behavioral, and epilepsy-specific data and the FB measured with the German version of the Impact on Family Scale before and after epilepsy surgery. RESULTS: The study cohort included 31 children with DRE at a mean age of 9 years at surgery (range = 0-16) and a mean epilepsy duration of 3 years (range = 0-14). Cognitive impairment correlated with FB in children with DRE prior to surgery. At the last assessment, 14.5 months (mean, range = 6-24) after epilepsy surgery, 87.2% of patients were seizure-free, FB values had decreased by 75.0%, and behavioral problems had decreased by 85,7%. Cognitive functions remained stable following epilepsy surgery. CONCLUSION: In children with DRE, epilepsy surgery reduces FB. Given the considerable impact of families on the development and wellbeing of their children, the impact of epilepsy surgery should be communicated to affected families.

How to define CSF overdrainage: a systematic literature review.

PURPOSE: Overdrainage (OD) is one of the most frequent complications related to drainage of the cerebrospinal fluid (CSF). It is mostly associated with valve-bearing shunt systems but should probably be considered as a risk factor in any type of CSF diversion procedure. There is extreme variation in the reported incidence of OD due to the lack of consensus on defining criteria and an unclear perception of the pathophysiology. Hence, OD is probably underreported and underestimated. The objective of this paper was to establish a definition of OD, based on a systematic review of the literature. METHODS: A systematic search was conducted in MEDLNE and EMBASE. Studies providing a definition or a description of diagnostic findings related to OD in ventriculoperitoneal shunt treated hydrocephalus were included. Non-English titles, abstracts and manuscripts were excluded. Extracted descriptions were graded into five groups (class I-V studies) based on how precise the terminology used to describe OD was. Class I studies were included for further analysis and characteristics of OD were extracted. The quality of included descriptions was assessed by a clinical expert panel. RESULTS: A total of 1309 studies were screened, 190 were graded into groups, and 22, which provided specific definitions or descriptions of OD, were graded as class I studies. We extracted 32 different characteristics consistent with OD (e.g., clinical symptoms, radiological signs, and syndromes). CONCLUSION: There was an overall agreement that CSF overdrainage following implantation of a ventriculoperitoneal shunt in a mixed pediatric and adult population is characterized as a persistent condition with clinically manifestations as postural dependent headache, nausea, and vomiting and/or radiological signs of slim ventricles and/or subdural collections.