Atretic cephalocele associated with sinus pericranii: a single-center analysis.

PURPOSE: The purpose of this report is to investigate the association of atretic cephalocele (AC) with sinus pericranii (SP) in order to improve the management of AC. METHODS: Pediatric patients with AC who underwent repair surgeries were retrospectively analyzed. Anomalies including SP were evaluated using computed tomography angiography and venography (CTA/V) as well as magnetic resonance imaging. RESULTS: Fourteen patients were identified, comprising of 5 males and 9 females. The AC was located interparietally in 8 cases and occipitally in 6 cases. Seven cases (50%) were found to be associated with SP, all of which did not involve major intracranial venous circulation. Five out of 8 parietal ACs (63%) were accompanied by SP, while 2 out of 6 occipital ACs (33%) exhibited SP. All of the SP associated with AC only contributed to a small portion of the venous outflow, and the repair surgeries were successfully performed without excessive bleeding. CONCLUSION: More than half of the ACs were associated with SP, with a higher prevalence in the parietal region compared to the occipital region. For the appropriate management of AC, preoperative investigation of SP using CT venography is considered important.

Alteration of major venous drainage routes in a patient with achondroplasia after ventriculoperitoneal shunt placement.

Achondroplasia is the most common form of dwarfism, caused by a mutation in fibroblast growth factor receptor 3 gene, leading to multiple pathological conditions. Herein, we present a case of an infant with achondroplasia associated with hydrocephalus and severe foramen magnum stenosis. Computed tomography (CT) venography showed prominent suboccipital emissary veins comprising major venous drainage routes and hypoplastic transverse sinuses, which increased the risk of foramen magnum decompression. The infant was initially treated with ventriculo-peritoneal (VP) shunt. After 8 months, CT venography showed regression of suboccipital emissary veins and more prominent transverse sinuses. Subsequently, foramen magnum decompression was safely performed without sacrificing major venous drainage routes.

Second-look surgery for pineal region tumors.

PURPOSE: Surgical resection of pineal region tumors is challenging because of close proximity to the vein of Galen draining system and the quadrigeminal plate. Surgical resection usually is performed through the narrow corridor by piecemeal resection and en bloc resection is difficult in cases of large tumors. Moreover, in cases of hypervascular tumors, surgical resection through the narrow corridor could entail massive intraoperative bleeding. The effectiveness of neoadjuvant chemotherapy and second-look surgery for pineal region tumors for maximal safe resection was evaluated. METHODS: Retrospective institutional review of pediatric patients with pineal region tumors who underwent second look surgery after neoadjuvant chemotherapy was performed. RESULTS: Nine patients underwent surgical resection after neoadjuvant chemotherapy over the period of September 2017 to February 2022. The mean age was 7.7 years (ranged from 1.4 to 15.3 years). Three patients underwent partial resection via open craniotomy, and 6 underwent endoscopic biopsy as an initial surgery. The histopathological diagnoses were germ cell tumors in 5 patients (yolk sac tumors in 2, germinoma in 2, choriocarcinoma in 1), /rhabdoid tumor (AT/RT) in 2, medulloblastoma in 1, and high-grade glioneuronal tumor in 1. After several courses of chemotherapy, the second-look surgery was performed. The tumor volume was reduced in 8 patients (89%) after chemotherapy except for 1 case of growing teratoma syndrome. The tumor was extended laterally to the ambient cistern in 2 patients, and posteriorly to the tentorial surface of the cerebellum in 3 patients. The lesion was approached through occipital transtentorial approach in 8 patients and infratentorial supracerebellar approach in 1. Intraoperatively, the high vascularity of the tumor was not observed in all cases. Gross total resection (8 patients, 89%) or near total resection (1, 11%) was achieved in all cases. No complications were observed postoperatively in all cases. Eight patients subsequently underwent additional chemo-radiation therapy according to the initial diagnosis. All patients are alive with no evidence of recurrence with a mean follow-up of 33 months. CONCLUSIONS: Neoadjuvant chemotherapy and second-look surgery for pediatric pineal region tumors was considered to be effective in reducing the tumor volume and vascularity, which facilitates the safe maximal tumor resection.

Pineal/germ cell tumors and pineal parenchymal tumors.

INTRODUCTION: Pineal region tumors (PRTs) are tumors arising from the pineal gland and the paraspinal structures. These tumors are rare and heterogeneous that account for 2.8-10.1% and 0.6-3.2% of tumors in children and in all ages, respectively. Almost all types and subtypes of CNS tumors may be diagnosed in this region. These tumors come from cells of the pineal gland (pinealocytes and neuroglial cells), ectopic primordial germ cells (PGC), and cells from adjacent structures. Hence, PRTs are consisted of pineal parenchyma tumors (PPTs), germ cell tumors (GCTs), neuroepithelial tumors (NETs), other miscellaneous types of tumors, cystic tumors (epidermoid, dermoid), and pineal cyst in addition. The symptoms of PRTs correlate to the increased intracranial cranial pressure due to obstructive hydrocephalus and dorsal midbrain compression. The diagnostic imaging studies are mainly MRI of brain (with and without gadolinium) along with a sagittal view of whole spine. Serum and/or CSF AFP/ß-HCG helps to identify GCTs. The treatment of PRTs is consisted of the selection of surgical biopsy/resection, handling of hydrocephalus, neoadjuvant and/or adjuvant therapy according to age, tumor location, histopathological/molecular classification, grading of tumors, staging, and threshold value of markers (for GCTs) in addition. METHODS: In this article, we review the following focus points: 1. Background of pineal region tumors. 2. Pineal GCTs and evolution of management. 3. Molecular study for GCTs and pineal parenchymal tumors. 4. Review of surgical approaches to the pineal region. 5. Contribution of endoscopy. 6. Adjuvant therapy (chemotherapy, radiotherapy, and combination). 7. RESULTS: In all ages, the leading three types of PRTs in western countries were PPTs (22.7-34.8%), GCTs (27.3-34.4%), and NETs (17.2-28%). In children and young adults, the leading PRTs were invariably in the order of GCTs (40-80.5%), PPTs (7.6-21.6%), NETs (2.4-37.5%). Surgical biopsy/resection of PRTs is important for precision diagnosis and therapy. Safe resection with acceptable low mortality and morbidity was achieved after 1970s because of the advancement of surgical approaches, CSF shunt and valve system, microscopic and endoscopic surgery. Following histopathological diagnosis and classification of types and subtypes of PRTs, in PPTs, through molecular profiling, four molecular groups of pineoblastoma (PB) and their oncogenic driver were identified. Hence, molecular stratified precision therapy can be achieved. CONCLUSION: Modern endoscopic and microsurgical approaches help to achieve precise histopathological diagnosis and molecular classification of different types and subtypes of pineal region tumors for risk-stratified optimal, effective, and protective therapy. In the future, molecular analysis of biospecimen (CSF and blood) along with AI radiomics on tumor imaging integrating clinical and bioinformation may help for personalized and risk-stratified management of patients with pineal region tumors.

Longstanding overt ventriculomegaly diagnosed in adolescents, not adults: a pediatric case report.

BACKGROUND: Longstanding overt ventriculomegaly in adults (LOVA) is a new form of progressive hydrocephalus characterized by onset in early childhood and gradual progression into adulthood. Patients with LOVA are usually asymptomatic in childhood. The diagnosis of LOVA in adolescence has not been reported. CASE REPORT: A patient with macrocephaly and mild ventriculomegaly from infancy developed headache exacerbation and cognitive dysfunction at the age of 11 years. Brain magnetic resonance imaging showed mild tri-ventriculomegaly with no radiological aggravation compared to imaging at the age of 8 years. No papilledema was observed. Drainage of 15 ml of spinal fluid via a lumbar puncture relieved the headache and cognitive dysfunction. Based on repeated improvements in cognitive function and headaches after spinal fluid drainage, we diagnosed the patient with LOVA with symptom onset in early adolescence. A ventriculoperitoneal shunt was placed, and the headaches disappeared completely. The full-scale intellectual quotient, verbal comprehension, and working memory improved significantly. CONCLUSIONS: LOVA may manifest as early as adolescence. The clinical presentation, age, clinical, radiological features, and management vary, and a spinal tap exam is useful for diagnosing LOVA, even in children. The spinal tap exam may be indicated in children with longstanding ventriculomegaly and deteriorating neurological symptoms to diagnose this "treatable intellectual disability."

A neonatal purely prepontine arachnoid cyst: a case report and review of the literature.

Purely prepontine arachnoid cysts not extending into the suprasellar region in neonates are rare. Herein, we report a purely prepontine arachnoid cyst in a neonate which caused central apnea and was successfully treated with microscopic cyst fenestration and C1 laminectomy.

[Pediatric Posterior Fossa Tumors].

Posterior fossa tumors tend to entail obstructive hydrocephalus, and urges initiating prompt treatment. Prevalent pathologies include medulloblastoma, ependymoma, pilocytic astrocytoma, and atypical teratoid/rhabdoid tumor(AT/RT). In most cases, maximal safe resection is related to better prognosis. In some cases of ependymoma and AT/RT with high vascularity, second-look surgery with neoadjuvant chemotherapy is effective. The treatment strategy should be tailored according to each tumor.

Endoscopic third ventriculostomy and cerebrospinal fluid shunting for pure communicating hydrocephalus in children.

PURPOSE: Recent reports regarding endoscopic third ventriculostomy (ETV) for pediatric hydrocephalus revealed that ETV could avoid cerebrospinal fluid (CSF) shunting in certain types of hydrocephalus. However, the effectiveness of ETV for "pure" communicating hydrocephalus that has no obstruction through CSF pathway is still unknown. In this study, we report clinical outcome of ETV and CSF shunting for communicating hydrocephalus and discuss the efficacy of ETV for pure communicating hydrocephalus. METHODS: Children less than 15 years old who underwent ETV or CSF shunting for communicating hydrocephalus were retrospectively reviewed. The absence of obstruction through CSF circulation was confirmed by CT cisternography or cine-contrast image in MRI. RESULTS: Sixty-three patients (45 CSF shunting and 18 ETV) were included. The mean follow-up period was 6.1 years. The success rate was 60% in CSF shunting and 67% in ETV at the last visit (p = 0.867). Normal development was observed in 24 patients (53%) in CSF shunting and 12 patients (67%) in ETV (p = 0.334). There was a significant difference in the mean time to failure (CSF shunting: 51.1 months, ETV 3.6 months, p = 0.004). The factor that affected success rate in ETV was the age at surgery (success 21.6 months, failure 4.4 months, p = 0.024) and ETV success score (success 66.7, failure 50.0, p = 0.047). CONCLUSION: Clinical outcomes of ETV were not inferior to those of CSF shunting in patients with communicating hydrocephalus. Further studies is required to elucidate to establish the consensus of ETV as a treatment option for communicating hydrocephalus.

Infantile intraorbital Ewing's sarcoma: case report and review of the literature.

We reported a 7-month-old female with intraorbital Ewing's sarcoma. Infantile Ewing's sarcoma is rare and its prognosis is poor. Ewing's sarcoma of orbital origin is even rare. There has been only 1 case of infantile intraorbital Ewing's sarcoma reported, and only 5 infantile primary orbital ESFTs (Ewing's sarcoma family of tumors) have been reported. Among these 5 cases, 2 infants who did not receive multimodal therapy died, whereas 3 who received multimodal therapy demonstrated long-term survival. The present case was also treated with multimodal therapy consisting of surgery, chemotherapy, and proton beam radiotherapy. There is no recurrence at 15 months follow-up. No specific treatment strategies have been established yet, and accumulation of cases is necessary. Ewing's sarcoma should be included in the differential diagnosis of infantile intraorbital tumors.

Deleterious fibronectin type III-related gene variants may induce a spinal extradural arachnoid cyst: an exome sequencing study of identical twin cases.

PURPOSE: Despite numerous studies, the etiology of spinal extradural arachnoid cyst (SEDAC), a lesion associated with neurological symptoms, remains unknown. In this genomic twin study, we investigated the genetic etiology of SEDACs. METHODS: The subjects were identical twins who developed notably similar SEDACs at the same vertebral level. Accordingly, we performed whole-exome sequencing analyses of genomic material from the twins and their parents using a next-generation sequencer. Additionally, we determined their detailed family history and analyzed the family pedigree. RESULTS: The pedigree analysis suggested the potential presence of SEDACs in certain family members, indicating a genetic disease. Sequenced data were analyzed and filtered using a purpose-built algorithm, leading to the identification of 155 novel single-nucleotide polymorphisms (SNPs), of which 118 encoded missense or nonsense variants. A functional analysis of the proteins encoded by these SNP alleles revealed strong enrichment for the fibronectin type III (FN3) protein domain (q = 0.00576). Specifically, the data indicated that a missense variant affecting the FN3 protein domain of fibronectin 1 (FN1, p.P969S) can be the causal mutation underlying the SEDACs. CONCLUSION: The data suggest that deleterious mutations in fibronectin-related genes may cause SEDACs. In particular, it was suspected that a variant of FN1 may be the cause of the SEDACs in the twin cases studied herein. Detailed studies with a larger number of cases are needed.

[Pediatric Glioma].

Pediatric gliomas include various types of glioma broadly categorized as low- or hi-grade based on histopathological features. Clinically significant types include cerebellar astrocytomas, optic pathway / hypothalamic pilocytic astrocytomas, and brainstem gliomas. Neurosurgical roles vary for different kinds of pediatric gliomas. Since these representative tumors remain rare, the patients should be directed toward facilities with experienced neurosurgeons. Radiotherapy and chemotherapy are very important as either adjuvant or primary treatment modalities. Recent advancements in molecular biology have revealed unique genetic aberrations in different types of pediatric gliomas. The RAS/MAPK pathway anomalies, including BRAF-KIAA1549 fusion and BRAF V600E mutation, are present in most low-grade gliomas. BRAF/MEK-inhibitors have yielded promising clinical study results. Diffuse midline gliomas, including diffuse intrinsic pontine gliomas, often harbor H3 mutations such as H3K27M. Agents that target these molecular aberrations are unavailable. Because gliomas in infants are sub-categorized by their genetic abnormalities, novel agents targeting ALK, ROS1, or NTRK fusions are promising treatments.

Surgical outcomes by sectioning a filum terminale in patients with terminal syringomyelia.

BACKGROUND: Although terminal syringomyelia suggests a tethered spinal cord, a consensus has still not been established for surgical indications, when there are no associated abnormalities or only minor associated abnormalities. We analyzed surgical outcomes of sectioning a filum terminale in patients with terminal syringomyelia to elucidate the significance of untethering surgery. METHODS: Fifty-seven pediatric patients with terminal syringomyelia who underwent untethering via sectioning the filum terminale between 2007 and 2018 were retrospectively analyzed. Postoperative outcomes of symptoms and MRI findings were evaluated. RESULTS: Of 57 patients, 40 had other associated abnormalities (25 with filar lipoma and 29 with low conus medullaris) that could be responsible for tethered cord. Nineteen patients had symptoms. The mean age at the time of surgery was 18 months (3-96 months). The mean follow-up period was 3.3 years (1-9 years). Preoperative symptoms improved in 9 patients (47%) after surgery. At 1 year after the surgery, the size of syringomyelia decreased in 19 (33%), increased in 4 (8%), and did not change in 34 (69%) patients. Of 28 patients who were followed up for more than 3 years, the size decreased in 17 (61%), increased in 1 (4%), and did not change in 10 (35%). CONCLUSION: When untethering was performed by sectioning a filum terminale, the size of terminal syringomyelia decreased in more than half of patients in the long term. Sectioning the filum terminale demonstrated the possibility of radiological and clinical improvement in patients with terminal syringomyelia.

Radiologically occult cervical intradural dermal sinus tract: a case report and review of literature.

We report the unusual case of a 7-month-old girl presenting with congenital cervical dermal sinus tract in which the intradural tract was not detected on preoperative imaging and was identified intraoperatively. Considering possible devastating sequelae of infection, excision of dermal sinus tract might be justified even in the case with radiologically undetected intradural tract.

Neoadjuvant chemotherapy for atypical teratoid rhabdoid tumors (AT/RTs).

PURPOSE: Atypical teratoid rhabdoid tumor (AT/RT) is a rare, clinically highly malignant tumor. The extent of the surgical resection may affect survival. However, it is often difficult to perform gross total resection (GTR) at an initial surgery because of the large tumor size and high vascularity. Neoadjuvant chemotherapy may reduce not only the size but also the vascularity. We report our experience, review the literature, and analyze its effectiveness. METHODS: A retrospective chart review of patients who underwent neoadjuvant chemotherapy and second-look surgery was performed. Demographic data, treatment courses, changes in tumor after the chemotherapy, extent of resection and estimated blood loss (EBL) during the second-look surgery, and outcome of each children were evaluated. RESULTS: There are 4 cases. The average age at diagnosis was 13.3 months (2-30 months). Two to 4 courses of neoadjuvant chemotherapy were performed. MRI after the chemotherapy showed reduction of tumor volume, and tumor vascularity at the second-look surgery decreased in all cases. GTR was achieved in 3 cases, and NTR in 1 case. The mean EBL/estimated blood volume (EBL/EBV) was 21.3% (1.5-39%). The mean follow-up period was 23 months (2-48 months). At the last follow-up, 2 patients were alive without recurrence of the tumor (the follow-up periods were 48 and 16 months). CONCLUSIONS: Neoadjuvant chemotherapy for AT/RTs might reduce both tumor size and vascularity, which enabled the maximal tumor resection. It may contribute to improve the prognosis of AT/RT through facilitating the tumor resection.

Long-term outcomes in pediatric unruptured brain arteriovenous malformation treated by nonconservative management: a single center analysis.

PURPOSE: The best management of pediatric unruptured brain arteriovenous malformations (ubAVM) should be further elucidated. METHODS: Pediatric patients who presented to our facility with ubAVM and were treated nonconservatively were retrospectively analyzed regarding demographics, presenting symptoms, AVM characteristics, treatment modality, and outcome. RESULTS: Thirteen patients were included. There were 9 male and 4 female patients with an average age (± SD) of 7.8 ± 4.6 years. The most common presenting symptom was seizure. The mean Spetzler Martin (SM) grade was 3.2. Seven patients were treated by surgical excision, 8 by embolization, 6 by radiosurgery, and during the mean follow-up period of 8.9 years (2.6-14.4 years), there were no hemorrhage. Complete ubAVM obliteration was achieved in all 7 patients (100%) who underwent surgical excision. AVM was obliterated in 5 out of 9 patients whose SM grade was 3 or 4. Modified Rankin scale was good (mRS 0-2) in all 13 patients. CONCLUSIONS: Since the lifetime hemorrhage rate of pediatric ubAVM is high, it may be better to proceed with nonconservative treatment, especially when surgical excision is amenable. Nonconservative treatment could be an appropriate treatment with acceptable neurological outcome even in those with moderate to high-grade AVMs in selected cases.

Pediatric meningiomas: a report of 5 cases and review of literature.

PURPOSE: The purpose of this paper is to provide novel insight into the rare pediatric meningiomas. METHODS: We retrospectively analyzed pediatric surgical cases of meningioma during 2002 to 2017 in our institution. The preoperative, intraoperative, and the postoperative status were collected to find any unique features that has not reported in the past. RESULTS: Nine surgeries out of 5 patients were identified. The mean age was 7 years old (range 1-14 years old). Four patients were females. The mean tumor diameter was 52 mm (range 23-81 mm). The tumor locations were optic nerve sheath, Sylvian fissure, parasagittal, trigone of the lateral ventricle, and cerebellopontine angle. The Sylvian fissure meningioma without dural attachment (MWODA) was found in a 15-month-old female. A relapsed parasagittal meningioma showed regression in histological grade and residual tumor demonstrated spontaneous regression. In the initial surgeries, Simpson grade 1 resection was achieved in 2 cases. The pathological diagnoses were 1 meningothelial, 1 metaplastic, 2 atypical, and 1 clear cell meningiomas. The mean postoperative follow-up period was 71 months. Three patients experienced recurrence of the tumor. At the latest follow-up, all patients were free of radiological tumor recurrence or regrowth with a mean follow-up of 4 years (range 1-6.9 years). All patients were in the modified Rankin scale of 0-1. CONCLUSIONS: MWODA is not considered to be rare in pediatric meningioma and should be included in the differential diagnosis. We presented a histologically regressed relapsed meningioma, which spontaneously regressed after subtotal resection. In the case of recurrent meningioma, surgical resection and adjuvant radiation therapy could be effective for long-term control of the tumor.

Pediatric nodular fasciitis at the roof of the optic canal causing decreased vision: case report and review of the literature.

We present a 3-year-old girl with decreased visual acuity of the left eye. Radiological studies revealed a mass lesion at the roof of the left optic canal with bony erosion, which compressed the left optic nerve. Gross total resection of the mass and decompression of the optic canal were performed. Histopathological study was consistent with nodular fasciitis. This is the first report of nodular fasciitis at the roof of the optic canal in a young child. Nodular fasciitis compressing the optic nerve should be included in differential diagnoses of optic neuropathy in young children.

Pediatric intracranial lower cranial nerve schwannoma unassociated with neurofibromatosis type 2: case report and review of the literature.

INTRODUCTION: Pediatric schwannomas are rare, and most of them are associated with neurofibromatosis type 2 (NF2) and usually located in the vestibular nerve. Herein, we present the first pediatric case of intracranial schwannoma derived from the IX/X nerve complex unrelated to NF2. CASE REPORT: The patient was a 9-year-old boy who presented with a 3-month history of headache and nausea. There was no family history of NF2. Imaging studies revealed a cystic lesion with enhanced wall in the left cerebellomedullary fissure. During the operation, the IX/X nerve complex was strongly adhered to the tumor at the jugular foramen. The tumor was totally excised, and the postoperative MRI demonstrated no residual tumor. Histopathological diagnosis was schwannoma. Genetic analysis revealed no mutation associated with NF2 and schwannomatosis. CONCLUSION: We reported the first case of pediatric lower cranial nerve schwannoma which was not associated with NF2. The schwannoma should be included as differential diagnosis of pediatric posterior fossa tumors.

Characteristics of Recurrent Congenital Sinus Pericranii: Case Report and Review of the Literature.

INTRODUCTION: Sinus pericranii (SP) involves transosseous vessels that connect the intra- and extracranial venous systems. Accessory-type SP can be cured by surgical or endovascular treatment. Reports of recurrence are, however, rare. CASE: A boy presented with a soft-tissue mass on the left parietal region of the head. Computed tomography and magnetic resonance imaging revealed the congenital SP with several small transosseous vessels surrounded by an area of thin bone. At the initial surgery, the vascular mass was completely excised by coagulating and cutting the -transosseous vessels. The skull defect was filled with bone wax. Two years later, SP recurred at the same site. At the second surgery, the skull defect and surrounding area were sealed with acrylic resin. The boy has been followed up for 6 years without recurrence. DISCUSSION: Potential risk factors for recurrence proposed in the existing literature include an unusually large number of emissary veins, rich circulation between intra- and extracranial venous systems, large bone defects, raised intracranial pressure, and association of other developmental venous anomalies. Our case demonstrates that thin skull bone around the original lesion can be another risk factor for recurrence. CONCLUSION: Removing all abnormal vessels and sealing the skull defect as well as the surrounding thin bone area are important to prevent recurrence of congenital SP.

Radiologically occult medulloblastoma with hydrocephalus: case report.

INTRODUCTION: There have been no reports of occult medulloblastoma nor noncommunicating hydrocephalus due to radiologically occult brain tumors. Herein, we report radiologically occult medulloblastoma with noncommunicating hydrocephalus. CASE REPORT: A 3-year-old boy presented with macrocephaly, visual field constriction, and papilledema. Neuroimagings showed enlargement of the ventricles without any mass lesions. The CT cisternography did not show influx of the contrast into the ventricles, which suggested local cerebrospinal fluid (CSF) circulatory disturbance at the outlet of the fourth ventricle. Due to possible obstructive nature of hydrocephalus, endoscopic third ventriculostomy (ETV) was performed. Three months after the ETV, he presented with repeated vomiting. Neuroimagings showed a 3-cm fourth ventricular mass with progressive hydrocephalus. Surgical resection was performed, which revealed the pathology was medulloblastoma. CONCLUSION: We report the case of radiologically occult medulloblastoma which was demonstrated radiologically in the follow-up period of ETV for noncommunicating hydrocephalus of uncertain etiology. This is the first description of a radiologically occult medulloblastoma and also the first description of an occult brain tumor with noncommunicating hydrocephalus. The occult brain tumor may be included in the etiology of hydrocephalus.