Spontaneous regression of migrated ventriculoperitoneal shunt catheter from scrotum to peritoneum: a case-based review.

OBJECTIVE: The incidence of scrotal migration of a ventriculoperitoneal shunt (VPS) catheter is rare and may lead to life-threatening visceral complications. Management requires prompt removal of the migrated portion of the shunt and closure of the scrotal sac. We report an interesting case of a young child who presented with asymptomatic unilateral swelling of his scrotum secondary to a migrated VPS catheter. A repeat X-ray prior to his surgery to remove the migrated catheter showed that the entire length of the distal VPS catheter was back in the peritoneal cavity. In view of this unusual phenomenon, the case is discussed in corroboration with published literature. METHODS AND RESULTS: A systematic search of publications in the English language is performed in PubMed and Google Scholar. Our findings show that there are 49 reported cases (including our patient) of scrotal migration of shunt catheters in patients less than 18 years old. There is only 1 other case of spontaneous resolution of shunt catheter from the scrotum. Favoured management of choice is repositioning the distal shunt catheter back into the peritoneal cavity and herniotomy in the same setting, if possible. Overall, the literature suggests this is a shunt-related complication that has a good prognosis if intervention is timely. CONCLUSION: Scrotal migration of a VPS catheter is a rare but potentially life-threatening complication in children. Our case report highlights the role of updated preoperative imaging and the need for consistent long-term shunt surveillance in children.

Neonatal intracranial haemorrhage secondary to vein of Galen aneurysmal dilatation.

Paediatric neurovascular anomalies associated with the vein of Galen (VG) comprise of a spectrum of rare, complex, and life-threatening conditions. In this group, the "vein of Galen aneurysmal dilatation" (VGAD) is a distinct entity that often presents with progressive neurological symptoms in older children. Acute haemorrhage in VGAD is uncommon. We present an unusual presentation of VGAD in a neonate and discuss the challenges faced in the management.

Cerebrospinal fluid shunt malfunctions: A reflective review.

PURPOSE: Pediatric hydrocephalus is a common and challenging condition. To date, the ventriculoperitoneal shunt (VPS) is still the main lifesaving treatment option. Nonetheless, it remains imperfect and is associated with multiple short- and long-term complications. This paper is a reflective review of the current state of the VPS, our knowledge gaps, and the future state of shunts in neurosurgical practice. METHODS AND RESULTS: The authors' reflections are based on a review of shunts and shunt-related literature. CONCLUSION: Overall, there is still an urgent need for the neurosurgical community to actively improve current strategies for shunt failures and shunt-related morbidity. The authors emphasize the role of collaborative efforts amongst like-minded clinicians to establish pragmatic approaches to avoid shunt complications.

Pediatric Primary Intracranial Malignant Melanoma: Case Report and Literature Review.

INTRODUCTION: Primary intracranial malignant melanoma (PIMM) is an extremely rare primary brain tumor with most cases diagnosed in adults. To date, there are only a few cases reported in the pediatric population. Owing to its infrequency, there are no established guidelines to treat this aggressive neoplasm. Recent insights suggest that PIMM are molecularly different between adults and children, whereby NRAS mutations drive tumor growth in the latter group. We present a unique case of PIMM in a pediatric patient and discuss the case in corroboration with current literature. CASE PRESENTATION: A previously well 15-year-old male presented with progressive symptoms of raised intracranial pressure. Neuroimaging reported a large solid-cystic lesion with significant mass effect. He underwent gross total resection of the lesion that was reported to be a PIMM with pathogenic single nucleotide variant NRAS p.Gln61Lys. Further workup for cutaneous, uveal, and visceral malignant melanoma was negative. A trial of whole-brain radiotherapy followed by dual immune checkpoint inhibitors was commenced. Despite concerted efforts, the patient had aggressive tumor progression and eventually demised from his disease. CONCLUSION: We therein report a case of pediatric PIMM, in the context of the patient's clinical, radiological, histopathological, and molecular findings. This case highlights the therapeutic difficulties faced in disease management and contributes to the very limited pool of medical literature for this devastating primary brain tumor.

Decompressive surgery in abusive head injury: Experience from a Singapore children's hospital and a review of literature.

PURPOSE: Abusive head trauma (AHT) is a major cause of morbidity and mortality in children. Studies on pediatric head injury observe that AHT patients often have a higher incidence of malignant cerebral oedema and, overall, worse prognosis. There are limited studies with a focus on the outcome of decompressive surgery in children with AHT. This is a study undertaken to review our institutional experience on the role of decompressive surgery in AHT patients and objectively assess its outcomes, in corroboration with current literature. METHODS: This is an ethics-approved, retrospective study. Inclusion criteria consist of all children with a diagnosis of AHT managed by the Neurosurgical Service, KK Women's and Children's Hospital. Demographical and clinical variables are incorporated in the statistical analyses. RESULTS: From 2011 to 2021, a total of 7 patients required decompressive surgery for AHT. Mean age of the cohort was 17.1 months (with the majority of patients being male (n = 5, 71.4%). During the follow-up period, there was 1 mortality (14.3%), 3 patients developed cerebral palsy (42.9%), and 3 patients had post-traumatic epilepsy (42.9%). With regards to functional outcome, 4 patients (57.1%) had a favorable KOSCHI score at 6 months follow-up. CONCLUSION: Decompressive surgery in children with AHT presents with its own unique challenges. We therein present our neurosurgical experience in decompressive surgery for this extremely vulnerable group of patients. Given the potential role of decompressive surgery in AHT, the development of an objective marker to select such patients who may benefit most from intervention should be the way forward.

Abusive head injury in the very young: outcomes from a Singapore children's hospital.

PURPOSE: Abusive head trauma (AHT) is a serious problem in children. The aims of this study are to identify risk factors that correlate with outcomes for those requiring neurosurgical intervention for very young children with AHT, assessment of variables associated with outcomes, and corroboration of our results with literature. METHODS: This is an ethics-approved, retrospective study. Inclusion criteria consisted of patients aged 2 years old or less with a diagnosis of AHT managed by the Neurosurgical Service, KK Women's and Children's Hospital. Demographical and clinical variables are incorporated in the statistical analyses. Logistic regression was applied to statistically significant variables for the risk prediction model. RESULTS: From 2000 to 2020, 24 patients required surgery for AHT. Timepoint was set at 12 months post-diagnosis. Univariate analyses demonstrated that patients with mild TBI were likely to have a favourable GOS-E Peds (p = 0.01), whereas radiological presence of cerebral oedema (p < .001), development of scar epilepsy (p = 0.021), and progression to cerebral palsy (p = 0.001) were associated with unfavourable GOS-E Peds. CONCLUSION: This is the first study focused on neurosurgical outcomes for very young children with AHT in Singapore. We advocate multidisciplinary efforts to improve outcomes for this devastating condition.

Tethered cord secondary to focal nondisjunction of the primary neural tube: experience from a Singapore children's hospital.

PURPOSE: Tethered cord due to focal nondisjunction of primary neuralisation (FNPN) is a rare form of spinal dysraphism. We present our institutional experience in managing children diagnosed with FNPN. MATERIALS AND METHODS: This is a single institution, retrospective study approved by the hospital ethics board. Patients below 18 years of age diagnosed with CDS, LDM or their mixed lesions, and subsequently underwent intervention by the Neurosurgical Service, KK Women's and Children's Hospital, are included. RESULTS: From 2001 to 2021, 16 FNPN patients (50% males) were recruited. Eight of them had CDS (50.0%), seven had LDM (43.8%), and one patient had a mixed CDS and LDM lesion (6.2%). The average duration of follow up was 5.7 years and the mean age of surgery was 6 months old. Thirteen patients underwent prophylactic intent surgery (81.2%) and three had therapeutic intent surgery (18.8%). All patients did not have new neurological deficit or required repeat surgery for cord retethering. We observed that detethering surgery performed at or less than three months old was associated with having a wound infection (p = .022). CONCLUSIONS: Our study reports that early recognition and timely intervention are mainstays of management for FNPN. We advocate a multi-disciplinary approach for good outcomes.

Neuroblastoma patient-derived cultures are enriched for a mesenchymal gene signature and reflect individual drug response.

Ex vivo evaluation of personalized models can facilitate individualized treatment selection for patients, and advance the discovery of novel therapeutic options. However, for embryonal malignancies, representative primary cultures have been difficult to establish. We developed patient-derived cell cultures (PDCs) from chemo-naïve and post-treatment neuroblastoma tumors in a consistent and efficient manner, and characterized their in vitro growth dynamics, histomorphology, gene expression, and functional chemo-response. From 34 neuroblastoma tumors, 22 engrafted in vitro to generate 31 individual PDC lines, with higher engraftment seen with metastatic tumors. PDCs displayed characteristic immunohistochemical staining patterns of PHOX2B, TH, and GD2 synthase. Concordance of MYCN amplification, 1p and 11q deletion between PDCs and patient tumors was 83.3%, 72.7%, and 80.0% respectively. PDCs displayed a predominantly mesenchymal-type gene expression signature and showed upregulation of pro-angiogenic factors that were similarly enriched in culture medium and paired patient serum samples. When tested with standard-of-care cytotoxics at human Cmax -equivalent concentrations, MYCN-amplified and non-MYCN-amplified PDCs showed a differential response to cyclophosphamide and topotecan, which mirrored the corresponding patients' responses, and correlated with gene signatures of chemosensitivity. In this translational proof-of-concept study, early-phase neuroblastoma PDCs enriched for the mesenchymal cell subpopulation recapitulated the individual molecular and phenotypic profile of patient tumors, and highlighted their potential as a platform for individualized ex vivo drug-response testing.

Cerebrospinal fluid cytokines in metastatic group 3 and 4 medulloblastoma.

BACKGROUND: Metastatic medulloblastoma (MB) portends a poor prognosis. Amongst the 4 molecular subtypes, Group 3 and Group 4 patients have a higher incidence of metastatic disease, especially involving the neuroaxis. At present, mechanisms underlying MB metastasis remain elusive. Separately, inflammation has been implicated as a key player in tumour development and metastasis. Cytokines and their inflammation-related partners have been demonstrated to act on autocrine and, or paracrine pathways within the tumour microenvironment for various cancers. In this study, the authors explore the involvement of cerebrospinal fluid (CSF) cytokines in Group 3 and 4 MB patients with disseminated disease. METHODS: This is an ethics approved, retrospective study of prospectively collected data based at a single institution. Patient clinicpathological data and corresponding bio-materials are collected after informed consent. All CSF samples are interrogated using a proteomic array. Resultant expression data of selected cytokines are correlated with each individual's clinical information. Statistical analysis is employed to determine the significance of the expression of CSF cytokines in Group 3 and 4 patients with metastatic MB versus non-metastatic MB. RESULTS: A total of 10 patients are recruited for this study. Median age of the cohort is 6.6 years old. Based on Nanostring gene expression analysis, 5 patients have Group 3 as their molecular subtype and the remaining 5 are Group 4. There are 2 non-metastatic versus 3 metastatic patients within each molecular subtype. Proteomic CSF analysis of all patients for both subtypes show higher expression of CCL2 in the metastatic group versus the non-metastatic group. Within the Group 3 subtype, the MYC-amplified Group 3 MB patients with existing and delayed metastases express higher levels of CXCL1, IL6 and IL8 in their CSF specimens at initial presentation. Furthermore, a longitudinal study of metastatic Group 3 MB observes that selected cytokines are differentially expressed in MYC-amplified metastatic Group 3 MB, in comparison to the non-MYC amplified metastatic Group 3 MB patient. CONCLUSION: This study demonstrates higher expression of selected CSF cytokines, in particular CCL2, in metastatic Group 3 and 4 MB patients. Although our results are preliminary, they establish a proof-of-concept basis for continued work in a larger cohort of patients affected by this devastating disease.

Primary paediatric epidural sarcomas: molecular exploration of three cases.

BACKGROUND: Primary paediatric epidural sarcomas are extremely rare. Overall, there remains a paucity of knowledge in paediatric epidural sarcomas owing to the infrequent number of cases. The Archer FusionPlex Sarcoma Kit (ArcherDX, Inc) is a next-generation sequencing assay that has been reported to be a useful technique to detect recurrent fusion in sarcomas. We report the molecular exploration of 3 primary paediatric epidural sarcomas-one in the cranium (mesenchymal chondrosarcoma) and 2 in the spine (mesenchymal chondrosarcoma and Ewing sarcoma respectively). CASE PRESENTATION: This is a study approved by the hospital ethics board. Clinico-pathological information from 3 consenting patients with primary epidural sarcomas was collected. These selected tumours are interrogated via Archer FusionPlex Sarcoma Kit (ArcherDX, Inc) for genomic aberrations. Results were validated with RT-PCR and Sanger sequencing. All findings are corroborated and discussed in concordance with current literature. Our findings show 2 variants of the HEY1-NCOA2 gene fusion: HEY1 (exon 4)-NCOA2 (exon 13) and HEY1 (exon 4)-NCOA2 (exon 14), in both mesenchymal chondrosarcoma patients. Next, the Ewing sarcoma tumour is found to have EWSR1 (exon 10)-FLI1 (exon 8) translocation based on NGS. This result is not detected via conventional fluorescence in situ testing. CONCLUSIONS: This is a molecularly-centered study based on 3 unique primary paediatric epidural sarcomas. Our findings to add to the growing body of literature for these exceptionally rare and malignant neoplasms. The authors advocate global collaborative efforts and in-depth studies for targeted therapy to benefit affected children.

The Seow Operative Score (SOS) as a decision-making adjunct for paediatric Chiari I malformation: a preliminary study.

PURPOSE: The natural history of Chiari I malformation (C1M) in the paediatric population is poorly understood. There are conflicting reports with regards to surgical indications, operative techniques and peri-operative prognostic indicators. In this paper, we report our institutional experience in the management of paediatric C1M. METHODS: The workflow process which includes preferred imaging modalities, surgical techniques and indications for intervention is discussed. In particular, we describe one of our current projects-an in-house designed Seow Operative Score (SOS) as a feasibility scoring system for neurosurgical intervention in our local cohort of paediatric C1M patients. RESULTS: In our series, we have 2 groups: 10 non-operated patients versus 19 operated patients. In the non-operated group, the majority of patients had a SOS of 0 to 1. One patient had a score of 2.5 and was kept under close surveillance. Follow-up imaging demonstrated resolution of the cerebellar herniation and intraspinal syrinx. In the operated group, 17 patients had a SOS of 3 or more. Two patients had a SOS of 2. For these 2, 1 developed progressive symptoms, and the other had an extensive cervico-thoracic syrinx. Decision was made for surgery after a period of surveillance. CONCLUSIONS: In this paper, we report our institutional experience in managing paediatric C1M and, at the same time, highlight salient points of our practices. Meanwhile, we advocate collective global efforts and in-depth research for better disease understanding of this challenging condition.

A germline variant of TP53 in paediatric diffuse leptomeningeal glioneuronal tumour.

PURPOSE: Diffuse leptomeningeal glioneuronal tumour (DLGNT) is an extremely rare tumour involving the neuroaxis. At present, its exact pathogenesis and associated factors remain incompletely characterised. Recent molecular investigations in a small cohort have offered some insights into this disease. However, the role of germline findings has not yet been fully explored in affected patients. The authors present a case of DLGNT, focusing on the clinical and molecular features with reference to current disease knowledge. METHODS: A 4-year-old male presented with raised intracranial pressure symptoms secondary to extensive leptomeningeal disease of the brain and spine. Preliminary impression was that of an inflammatory lesion. RESULTS: A lumbar biopsy of the lesion confirmed DLGNT on routine diagnostic examination. Further molecular analysis of his tumour and blood demonstrated a previously unreported TP53 exon 5 (c.147V > I) germline variant. Based on the latest DLGNT molecular subtyping classification, his tumour falls into the group with better clinical outcome. However, his germline findings may add an extra layer of uncertainty to his overall prognosis. CONCLUSION: Given that much remains unknown in many rare paediatric tumours at this stage, isolated findings found in an individual may be of significance. Supplementary genetic information, together with tumour molecular analysis, add to our current understanding of this uncommon disease. This case highlights the benefit of combined clinical and molecular efforts, including germline testing, especially for children affected by such challenging neoplasms.

Management of brain abscesses: where are we now?

INTRODUCTION: Brain abscesses affect all age groups and are not peculiar to a particular country, race, or geographical location. It is a disease that, in the past, carried a high morbidity and mortality. With improvements in medical technology and expertise, outcomes have improved tremendously. The causative organisms vary vastly and have evolved with time. Treatment of brain abscesses is primarily with antimicrobial therapy but surgery plays a vital role in achieving better outcomes. CONTENT: In this article, we review the literature to find out how the epidemiology of this disease has changed through the years and re-visit the basic pathological process of abscess evolution and highlight the new research in the biochemical pathways that initiate and regulate this process. We also highlight how magnetic resonance imaging and its various modalities have improved diagnostic accuracy. Finally, we discuss the pros and cons of traditional open surgery versus newer minimally invasive methods.

Post-operative diffusion weighted imaging as a predictor of posterior fossa syndrome permanence in paediatric medulloblastoma.

PURPOSE: Posterior fossa syndrome (PFS) is a serious complication faced by neurosurgeons and their patients, especially in paediatric medulloblastoma patients. The uncertain aetiology of PFS, myriad of cited risk factors and therapeutic challenges make this phenomenon an elusive entity. The primary objective of this study was to identify associative factors related to the development of PFS in medulloblastoma patient post-tumour resection. METHODS: This is a retrospective study based at a single institution. Patient data and all related information were collected from the hospital records, in accordance to a list of possible risk factors associated with PFS. These included pre-operative tumour volume, hydrocephalus, age, gender, extent of resection, metastasis, ventriculoperitoneal shunt insertion, post-operative meningitis and radiological changes in MRI. Additional variables included molecular and histological subtypes of each patient's medulloblastoma tumour. Statistical analysis was employed to determine evidence of each variable's significance in PFS permanence. RESULTS: A total of 19 patients with appropriately complete data was identified. Initial univariate analysis did not show any statistical significance. However, multivariate analysis for MRI-specific changes reported bilateral DWI restricted diffusion changes involving both right and left sides of the surgical cavity was of statistical significance for PFS permanence. CONCLUSION: The authors performed a clinical study that evaluated possible risk factors for permanent PFS in paediatric medulloblastoma patients. Analysis of collated results found that post-operative DWI restriction in bilateral regions within the surgical cavity demonstrated statistical significance as a predictor of PFS permanence-a novel finding in the current literature.

Pediatric de novo cerebral AVM: report of two cases and review of literature.

PURPOSE: Cerebral arteriovenous malformation (AVM) is traditionally thought of as a congenital diagnosis. In recent years, there has been infrequent reports of this neurovascular condition presenting as de novo entities. METHODS: The authors report two cases of pediatric patients who present with de novo cerebral AVMs. In both cases, the patients had magnetic resonance imaging (MRI) of the brain done as part of the work-up for first-onset seizures. At that point in time, the scans were unremarkable. After a latent period of approximately 6 and 9 years respectively, a repeated MRI brain scan showed evidence of de novo AVM for each patient. RESULTS: Both patients did not have radiological evidence of cerebral AVM during their first presentation of seizures. However, a repeated MRI brain scan after a period of 6 and 9 years demonstrated new findings of cerebral AVM for each patient. CONCLUSIONS: Currently, the disease of cerebral de novo AVM remain as an ambiguous condition that is poorly understood. With the advances in molecular diagnostics, there are possibilities of exploring biochemical profiles for better understanding of the origin of cerebral AVMs. However, in the meantime, owing to the unpredictable nature of cerebral AVMs, clinicians should have increased awareness of this unique condition. This is especially important, as definitive treatment is available to prevent devastating neurological sequelae from cerebral AVM rupture.

Selective dorsal rhizotomy using a 3D high definition exoscope.

Selective dorsal rhizotomy (SDR) is an established neurosurgical technique for children with spastic diplegia secondary to cerebral palsy. Meticulous intraoperative testing of individual nerve roots with electromyography in tandem with the on-site neurorehabilitation team is recommended for good clinical outcomes. The standard approach requires the neurosurgeons to spend extended time under the traditional operating microscope. In this video, the authors describe the use of a 3D exoscope system for SDR. Overall, the 3D exoscope improves ergonomics and reduces musculoskeletal fatigue for the operating neurosurgeons. Furthermore, it provides excellent visualization of important structures, allowing safe and efficient completion of the procedure. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23105.

Complex lumbosacral spinal cord lipomas: A longitudinal study on outcomes from a Singapore children's hospital.

BACKGROUND: Total/near-total resection (TR/NTR) of complex lumbosacral lipomas (CSL) is reported to be associated with better long-term functional outcomes and lower symptomatic re-tethering rates. We report our institutional experience for CSL resection in affected children. METHODS: This is a single-institution, retrospective study. Inclusion criteria consist of patients with CSL with dorsal, transitional and chaotic lipomas based on Pang et al's classification. The study population is divided into 2 groups: asymptomatic patients with a normal preoperative workup referred to as 'prophylactic intent' and 'therapeutic intent' for those with pre-existing neuro-urological symptoms. Primary aims are to review factors that affect post-operative clean intermittent catheterization (CIC), functional outcomes based on Necker functional score (NFS), and re-tethering rates. RESULTS: 122 patients were included from 2000 to 2021. There were 32 dorsal lipomas (26.2 %), 74 transitional lipomas (60.7 %), and 16 chaotic lipomas (13.1 %). 82 % patients achieved TR/NTR. Favourable NFS at 1-year was 48.2 %. The re-tethering rate was 6.6 %. After multivariable analysis, post-operative CIC was associated with median age at surgery (p = 0.026), lipoma type (p = 0.029), conus height (p = 0.048) and prophylactic intent (p < 0.001). Next, extent of lipoma resection (p = 0.012) and the post-operative CSF leak (p = 0.004) were associated with re-tethering. Favourable NFS was associated with lipoma type (p = 0.047) and prophylactic intent surgery (p < 0.001). CONCLUSIONS: Our experience shows that TR/NTR for CSL is a feasible option to prevent functional deterioration and re-tethering. Efforts are needed to work on factors associated with post-operative CIC.