Interaction of interictal epileptiform activity with sleep spindles is associated with cognitive deficits and adverse surgical outcome in pediatric focal epilepsy.

OBJECTIVE: Temporal coordination between oscillations enables intercortical communication and is implicated in cognition. Focal epileptic activity can affect distributed neural networks and interfere with these interactions. Refractory pediatric epilepsies are often accompanied by substantial cognitive comorbidity, but mechanisms and predictors remain mostly unknown. Here, we investigate oscillatory coupling across large-scale networks in the developing brain. METHODS: We analyzed large-scale intracranial electroencephalographic recordings in children with medically refractory epilepsy undergoing presurgical workup (n = 25, aged 3-21 years). Interictal epileptiform discharges (IEDs), pathologic high-frequency oscillations (HFOs), and sleep spindles were detected. Spatiotemporal metrics of oscillatory coupling were determined and correlated with age, cognitive function, and postsurgical outcome. RESULTS: Children with epilepsy demonstrated significant temporal coupling of both IEDs and HFOs to sleep spindles in discrete brain regions. HFOs were associated with stronger coupling patterns than IEDs. These interactions involved tissue beyond the clinically identified epileptogenic zone and were ubiquitous across cortical regions. Increased spatial extent of coupling was most prominent in older children. Poor neurocognitive function was significantly correlated with high IED-spindle coupling strength and spatial extent; children with strong pathologic interactions additionally had decreased likelihood of postoperative seizure freedom. SIGNIFICANCE: Our findings identify pathologic large-scale oscillatory coupling patterns in the immature brain. These results suggest that such intercortical interactions could predict risk for adverse neurocognitive and surgical outcomes, with the potential to serve as novel therapeutic targets to restore physiologic development.

Surgical treatment of interhemispheric arachnoid cysts.

OBJECTIVE: In children, interhemispheric arachnoid cysts (IHACs) are rare lesions often associated with corpus callosum dysgenesis. It is still controversial about surgical treatments for IHACs. We aim to report our experience with pediatric IHAC patients and evaluate surgical courses and neurological developments. METHODS: Pediatric IHACs treated between 2001 and 2021 were reviewed retrospectively. IHAC was observed until they represented rapid cyst enlargement or neurological symptoms. Cyst fenestration was done by microscope or endoscope, depending on the IHAC's location. Cyst size and corpus callosum dysgenesis were evaluated with neuroimaging. Neurological development was assessed from medical records at the last follow-up. RESULTS: Fifteen children received cyst fenestration surgery (mean age 11.4 months). Eleven patients (73.3%) under observation showed rapid cyst enlargement in a short period (median 5 months). Cysto-ventriculostomy (CVS) and cysto-cisternostomy (CCS) regressed the cyst size significantly (p = 0.003). The median follow-up duration was 51 months (range 14-178 months). Corpus callosum dysgenesis was observed in eleven patients (73.3%, complete = 5, partial = 6). Among eight patients (53.3%) having developmental delay, five patients (33.3%) showed speech delay, including one patient with intractable seizures. CONCLUSION: Pediatric IHACs frequently present within 1 year after birth, with rapid cyst enlargement. CVS and CCS were effective in regressing the cyst size. Corpus callosum dysgenesis accompanied by IHAC might have a risk of language achievement; however, development delay could rely on multifactorial features, such as epilepsy or other brain anomalies.

Suprasellar teratoma to germinoma recurrence: implications for diagnosis and follow-up.

Mature teratoma is a subtype of intracranial germ cell tumors (GCTs), distinguished from malignant GCTs by its benign nature and excellent prognosis. Typically, no adjuvant therapy is recommended following gross total resection (GTR). We report a case of a prepubertal girl with a suprasellar mature teratoma that recurred as a germinoma 6 months post-GTR. A 7-year-old girl presented with headache and polydipsia. Imaging revealed a suprasellar mass. The patient underwent GTR, and pathological diagnosis confirmed a mature teratoma without other GCT components. Six months later, MRI identified a newly developed suprasellar mass adjacent to the optic chiasm. A second surgery confirmed the mass as a germinoma. The patient subsequently underwent adjuvant chemotherapy combined with proton therapy, resulting in complete remission. The diagnosis of mature teratoma must be approached with caution, and thorough follow-up is imperative, particularly in cases involving female patients, prepubertal age, or non-pineal locations.

Identifying Risk Factors for Wound Complications Following Fronto-Orbital Advancement in Patients With Craniosynostosis: 3-dimensional Craniometrics Analysis.

This study aims to identify 3-dimensional (3D) craniometric predictors of wound complications following fronto-orbital advancement (FOA) surgery in craniosynostosis patients. The authors conducted a retrospective review of medical records for 43 patients (25 female, 18 male) who underwent open FOA between 2006 and 2023, with an average follow-up duration of 91.8 months. The data collected included age at surgery, sex, whether the craniosynostosis was syndromic, involvement of multiple sutures, history of suturectomy, wound complications (categorized as minor or major), and preoperative and postoperative 3D CT scans. The authors quantified relative changes in intracranial volume (ICV), cranial area above the Frankfurt Horizontal plane, anteroposterior diameter (APD), and cranial height (CH) using Mimics software. A logistic regression analysis was performed to identify predictors of wound complications post-FOA. Among the 43 patients who underwent FOA, 10 experienced postoperative wound complications (4 minor, 6 major), revealing significant associations with multisuture involvement and changes in △cranial area, △APD, and △CH (all P<0.05). In the multivariable analysis with backward elimination, △cranial area, and △CH were identified as significant risk factors for wound complications (OR 1.17, 95% CI: 1.01-1.36, P=0.032; and OR 0.59, 95% CI: 0.38-0.92, P=0.019, respectively). The cutoff values for △cranial area and △APD were 5.95% and 7.93%, respectively. This study identified measurable craniometric changes, especially in the cranial area, as risk factors for wound complications following FOA. It underscores the necessity for personalized surgical planning and meticulous postoperative wound care in FOA to enhance patient outcomes through risk-aware strategies.

Epigenetic Alteration of H3K27me3 as a Possible Oncogenic Mechanism of Central Neurocytoma.

Central neurocytoma (CN) is a low-grade neuronal tumor that mainly arises from the lateral ventricle (LV). This tumor remains poorly understood in the sense that no driver gene aberrations have been identified thus far. We investigated immunomarkers in fetal and adult brains and 45 supratentorial periventricular tumors to characterize the biomarkers, cell of origin, and tumorigenesis of CN. All CNs occurred in the LV. A minority involved the third ventricle, but none involved the fourth ventricle. As expected, next-generation sequencing performed using a brain-tumor-targeted gene panel in 7 CNs and whole exome sequencing in 5 CNs showed no driver mutations. Immunohistochemically, CNs were robustly positive for FGFR3 (100%), SSTR2 (92%), TTF-1 (Nkx2.1) (88%), GLUT-1 (84%), and L1CAM (76%), in addition to the well-known markers of CN, synaptophysin (100%) and NeuN (96%). TTF-1 was also positive in subependymal giant cell astrocytomas (100%, 5/5) and the pituicyte tumor family, including pituicytoma and spindle cell oncocytoma (100%, 5/5). Interestingly, 1 case of LV subependymoma (20%, 1/5) was positive for TTF-1, but all LV ependymomas were negative (0/5 positive). Because TTF-1-positive cells were detected in the medial ganglionic eminence around the foramen of Monro of the fetal brain and in the subventricular zone of the LV of the adult brain, CN may arise from subventricular TTF-1-positive cells undergoing neuronal differentiation. H3K27me3 loss was observed in all CNs and one case (20%) of LV subependymoma, suggesting that chromatin remodeling complexes or epigenetic alterations may be involved in the tumorigenesis of all CNs and some ST-subependymomas. Further studies are required to determine the exact tumorigenic mechanism of CN.

Headache in Pediatric Moyamoya Disease after Revascularization Surgery.

INTRODUCTION: Patients with moyamoya disease (MMD) often have headaches after successful revascularization surgery. We aimed to characterize headache in surgically treated MMD patients and elucidate its clinical meaning and pathophysiology. METHODS: Headache and related symptoms were surveyed using structured questionnaires in pediatric MMD patients with follow-up for 6 months or longer after indirect revascularization surgery. Clinical information including initial presentation, surgical method, and outcome was collected from medical records. Surgical outcomes were assessed clinically and by perfusion imaging. We defined "headache associated with MMD" as the headache accompanied by a transient ischemic attack or provoked by hyperventilation. Other headaches were further classified based on the diagnostic criteria of the International Headache Society-3. We analyzed the characteristics of "headache associated with MMD" and newly developed headache after surgery. RESULTS: Among 90 participants, 65 (72.2%) had headaches within the last year before survey, including 28 (43.1%) with "headaches associated with MMD," 10 (15.3%) with probable migraines, 2 (3.1%) with infrequent episodic tension-type headaches, and 4 (6.2%) with probable tension-type headaches. Headache quality was pulsatile in 27 (41.5%) patients and pressing or tightening in 27 (41.5%) patients. Nausea or vomiting was accompanied in 30 (46.2%) patients. Headache upon awakening was reported in 37 (57.8%) patients. Headache disturbed daily life in 12 (18.5%) patients. Among the 32 (35.6%) patients who suffered headache during both the pre- and postoperative period, the headache quality was similar in 27 (84.4%) patients, and its severity decreased in 24 (75.0%) and did not change in 8 (25.0%) patients. Twelve (13.3%) patients experienced newly developed headaches after surgery. Among them, six (50.0%) were classified as having "headaches associated with MMD." They were predominantly electric shock-like or stabbing in 5 (45.6%) patients and nondisturbing in all patients. All 90 patients achieved improvement of ischemic symptoms after surgery. CONCLUSION: Headaches often persist or newly develop after revascularization surgery in MMD patients. Accompanying nausea or vomiting and occurrence upon awakening are characteristic features. Postoperative headache does not necessarily imply insufficient disease control.

A case report of spinal toxocariasis with extensive tumor-like involvement.

BACKGROUND: Toxocariasis is a common parasitic infection worldwide. Although it can present as several clinical syndromes, neurological manifestation is rare. Only a few reports are available on spinal cord involvement of toxocariasis. We report a case that presented with gait disturbance due to progressive lower limb spasticity. The patient had had visceral toxocariasis infection 8 years before. A spine magnetic resonance image (MRI) showed syringomyelia along the entire thoracic cord with small nodular enhancing lesions in the mid-portion of the syrinx, which led to the suspicion of ependymoma. Surgical mass removal was performed. However, histopathological examination of the mass did not show any malignant cells; instead, there were numerous axonal retraction balls with an eosinophilic granular body-like appearance. The serum antibody titer against toxocariasis was borderline high. Taken together, these observations led to a diagnosis of Toxocara infection, and the patient was treated with albendazole. CONCLUSION: To the best of our knowledge, this is the first case report of tumor-like spinal toxocariasis involving extensive lesions. A solid enhancing mass with accompanied syrinx and hemorrhage might be a Toxocara infection. It can easily be diagnosed with serologic tests and simply be treated with oral albendazole if suspected.

Endoscopic biopsy of pineal tumors: two burr hole trans-foramen of Monro approach and endonasal trans-tuber cinereum approach.

INTRODUCTION: The pineal region is a challenging area for neurosurgeons due to its innate anatomical features, such as its deep location, surrounding large draining veins, and adjacent critical neural structures. DISCUSSION: There is a high proportion of malignant tumors in the pineal gland, especially in children, and they are frequently accompanied by obstructive hydrocephalus. These cases require that surgical procedures can make a pathological diagnosis to guide further treatment strategies and immediately resolve increased intracranial pressure. Simultaneous endoscopic third ventriculostomy and biopsy have been regarded as the first-line surgical intervention before establishing a definite treatment plan. However, it is not always successful because various factors affect the surgical procedures, such as the location and extent of the tumor, degree of ventriculomegaly, location and size of the massa intermedia, and size of the foramen of Monro. CONCLUSION: Here, we briefly reviewed the points to be considered in endoscopic biopsy of pineal tumors and introduced an alternative surgical procedure, the endoscopic endonasal trans-tuber cinereum approach, to surmount the anatomical hurdles.

Comparison of the clinical features and treatment outcomes of pilocytic astrocytoma in pediatric and adult patients.

PURPOSE: Pilocytic astrocytoma is a slow-growing tumor that predominantly develops in children, but has a broad age spectrum. A notable characteristic of pilocytic astrocytoma is that the tumor arises in diverse locations and the clinical course is not always benign. Therefore, it is necessary to elucidate the clinical spectrum of the disease and analyze the relevant prognostic factors. METHODS: Demographic and treatment-related factors were retrospectively reviewed in a cohort of 254 patients with histologically confirmed pilocytic astrocytoma. Clinical features were compared between the pediatric group (N = 208; age < 18 years) and the adult group (N = 46; age ≥ 18 years). Cox regression analysis was performed to identify relevant prognostic factors. RESULTS: There was no difference in progression-free survival (PFS) between the pediatric and adult groups (p = 0.36); however, patients under 8 years of age exhibited worse PFS (p < 0.01). Leptomeningeal seeding at diagnosis and pilomyxoid histology was observed only in pediatric patients. In the pediatric group, nine patients experienced recurrence after complete resection. Increasing age (hazard ratio (HR) = 0.89, p < 0.01) and adjuvant therapy (HR = 0.32, p < 0.01) were protective factors against tumor progression. In the adult group, no progression occurred after complete resection. Age and adjuvant therapy were not significant factors in the adult group. CONCLUSION: Pilocytic astrocytoma presents with a diverse clinical spectrum. Complete resection is of utmost importance, and appropriate adjuvant treatment is recommended if complete resection cannot be achieved. Children with younger age are associated with more aggressive tumors, and recurrence may occur even after complete resection.

Ultra-low-dose computed tomography with deep learning reconstruction for craniosynostosis at radiation doses comparable to skull radiographs: a pilot study.

BACKGROUND: Craniofacial computed tomography (CT) is the diagnostic investigation of choice for craniosynostosis, but high radiation dose remains a concern. OBJECTIVE: To evaluate the image quality and diagnostic performance of an ultra-low-dose craniofacial CT protocol with deep learning reconstruction for diagnosis of craniosynostosis. MATERIALS AND METHODS: All children who underwent initial craniofacial CT for suspected craniosynostosis between September 2021 and September 2022 were included in the study. The ultra-low-dose craniofacial CT protocol using 70 kVp, model-based iterative reconstruction and deep learning reconstruction techniques was compared with a routine-dose craniofacial CT protocol. Quantitative analysis of the signal-to-noise ratio and noise was performed. The 3-dimensional (D) volume-rendered images were independently evaluated by two radiologists with regard to surface coarseness, step-off artifacts and overall image quality on a 5-point scale. Sutural patency was assessed for each of six sutures. Radiation dose was compared between the two protocols. RESULTS: Among 29 patients (15 routine-dose CT and 14 ultra-low-dose CT), 23 patients had craniosynostosis. The 3-D volume-rendered images of ultra-low-dose CT without deep learning showed decreased image quality compared to routine-dose CT. The 3-D volume-rendered images of ultra-low-dose CT with deep learning reconstruction showed higher noise level, higher surface coarseness but decreased step-off artifacts, comparable signal-to-noise ratio and overall similar image quality compared to the routine-dose CT images. Diagnostic performance for detecting craniosynostosis at the suture level showed no significant difference between ultra-low-dose CT without deep learning reconstruction, ultra-low-dose CT with deep learning reconstruction and routine-dose CT. The estimated effective radiation dose for the ultra-low-dose CT was 0.05 mSv (range, 0.03-0.06 mSv), a 95% reduction in dose over the routine-dose CT at 1.15 mSv (range, 0.54-1.74 mSv). This radiation dose is comparable to 4-view skull radiography (0.05-0.1 mSv) and lower than previously reported effective dose for craniosynostosis protocols (0.08-3.36 mSv). CONCLUSION: In this pilot study, an ultra-low-dose CT protocol using radiation doses at a level similar to skull radiographs showed preserved diagnostic performance for craniosynostosis, but decreased image quality compared to the routine-dose CT protocol. However, by combining the ultra-low-dose CT protocol with deep learning reconstruction, image quality was improved to a level comparable to the routine-dose CT protocol, without sacrificing diagnostic performance for craniosynostosis.

The Outcomes of Endoscopic Suturectomy in Syndromic Craniosynostosis.

OBJECTIVE: Endoscopic suturectomy is a widely practiced surgical option for infants with craniosynostosis. But the efficacy and safety of the procedure remain unclear in syndromic patients. This study aims to evaluate the efficacy and safety of endoscopic suturectomy for patients with syndromic craniosynostosis. METHODS: From January 2013 to December 2020, 242 patients underwent endoscopic suturectomy at our institution. The surgical outcome was determined to be favorable or unfavorable based upon the necessity of an additional cranial surgery upon the last follow-up. First, we analyzed the outcomes of 26 syndromic craniosynostosis patients who have followed up for over a year. Second, we compared the outcomes between the syndromic (N=12) and nonsyndromic (N=11) patients with bilateral coronal synostosis who have followed up for over a year. RESULTS: Twenty-three out of 26 syndromic craniosynostosis patients (88%) showed favorable outcomes without significant complications. In the analysis for bilateral coronal synostosis patients, 11 of 12 syndromic patients (92%) presented favorable outcomes, and all nonsyndromic patients showed favorable outcomes. No significant differences were observed in various anthropometric indices (cranial index, intracranial volume, anterior cranial height, anterior cranial base length, and cranial height-length index) and surgical outcomes between syndromic and nonsyndromic groups. CONCLUSIONS: Endoscopic suturectomy has the potential to be a surgical option for syndromic craniosynostosis. Even for patients with unfavorable outcomes, endoscopic suturectomy could serve as a bridge treatment for infants to counter cranial deformation before additional extensive surgery.

Molecular subgrouping of medulloblastoma in pediatric population using the NanoString assay and comparison with immunohistochemistry methods.

PURPOSE: Molecular subgrouping of medulloblastoma has become important due to its impact on risk group stratification. Immunohistochemistry (IHC) has been widely used but it has innate limitations. The NanoString assay has been proposed as an alternative method. This study aims to present the characteristics of medulloblastoma subgrouped by the NanoString assay and to compare the subgrouping results with the IHC method. METHODS: Pediatric patients with histological diagnosis of medulloblastoma who underwent surgery from 2007 to 2021 were included. Clinical characteristics, pathological findings were reviewed. Molecular subgrouping was performed by IHC and by NanoString nCounter Elements TagSets assay. Test for concordance between two methods was made. RESULTS: Among a total of 101 patients analyzed, subgrouping using the NanoString assay resulted in 14 (13.8%) WNT, 20 (19.8%) SHH, 18 (17.8%) Group 3, and 39 (38.6%) Group 4 subgroup cases. Survival analysis revealed the following from best to worse prognosis: WNT, Group 4, SHH, and Group 3. In SHH subgroup the large cell/anaplastic histology was present in 30% of cases. Seventy-one cases were analyzed for concordance between NanoString and IHC. Cohen's kappa value indicated moderate agreement but identification of Groups 3 and 4 with IHC using NPR3 and KCNA1 markers exhibited poor results. CONCLUSIONS: The NanoString assay of Korean medulloblastoma patients revealed a more aggressive clinical course in the SHH subgroup which may be explained by a higher proportion of large cell/anaplastic histology being present in this subgroup. IHC did not distinguish Group 3 or 4 accurately. The NanoString assay may represent a good alternative method for practical use in the clinical field.

Outcomes of intracranial non-germinomatous germ cell tumors: a retrospective Asian multinational study on treatment strategies and prognostic factors.

PURPOSE: Non-germinomatous germ cell tumors (NGGCTs) are rare pediatric conditions. This multicenter study using Asian multinational patient data investigated treatment outcomes and prognostic factors for NGGCTs. METHODS: Medical records of 251 patients with NGGCTs treated from 1995 to 2015 were retrospectively analyzed from participating centers in Asian countries (Korea, Taiwan, Singapore, and Japan). RESULTS: The median follow up was 8.5 years (95% CI 7.8-9.9). In the total cohort, 5-year event-free survival (EFS) and overall survival (OS) rates were 78.2% and 85.4%, respectively. In 17.9% of the patients, diagnosis was determined by tumor markers alone (alpha-fetoprotein ≥ 10 ng/mL (Korea) or > 25 ng/mL (Taiwan and Singapore), and/or ß-human chorionic gonadotropin (ß-hCG) ≥ 50 mIU/mL). Patients with immature teratomas and mature teratomas comprised 12.0% and 8.4%, respectively. The 5-year EFS rate was higher in patients with histologically confirmed germinoma with elevated ß-hCG (n = 28) than those in patients with malignant NGGCTs (n = 127). Among malignant NGGCTs, patients with choriocarcinoma showed the highest 5-year OS of 87.6%, while yolk sac tumors showed the lowest OS (68.8%). For malignant NGGCT subgroups, an increase in serum ß-hCG levels by 100 mIU/mL was identified as a significant prognostic factor associated with the EFS and OS. CONCLUSION: Our result shows excellent survival outcomes of overall CNS NGGCT. However, treatment outcome varied widely across the histopathologic subgroup of NGGCT. Hence, this study suggests the necessity for accurate diagnosis by surgical biopsy and further optimization of diagnosis and treatment according to the histopathology of NGGCTs. Future clinical trials should be designed for individualized treatments for different NGGCTs subsets.

The stability of multifocal ventriculoperitoneal shunts with Y-connections.

PURPOSE: Multifocal ventriculoperitoneal shunts with Y-connections (MVPS with Ys) are widely used in many centers when neuroendoscopic procedures on entrapped ventricles are not feasible; however, their use is not frequent. This study aimed to confirm the stability of an MVPS with Y and, for the first time, identify the factors that influence stability. METHODS: We studied 33 consecutive patients who underwent initial conversion to MVPS with Ys. The one-year overall shunt survival rate was calculated and compared with the historical outcome of single ventriculoperitoneal shunts (VPSs). The factors influencing the one-year overall shunt survival rate were also investigated. The one-year survival rate for proximal catheters in each location was further investigated, and the rates were compared among locations. The factors affecting proximal catheter survival were determined. RESULTS: The one-year overall shunt survival rate of MVPS with Y was 70%, which was not much different from that of previously reported single VPSs, including our institution. We found no significant factor influencing overall shunt survival, but when an additional catheter was inserted into the fourth ventricle, the survival rate was exceptionally low at 40% (p = 0.21). When we investigated the one-year survival rate of each proximal catheter, we found that the location of the proximal catheter showed a certain trend toward significance (p = 0.07), especially in the case of the fourth ventricle, which had the lowest survival rate at 57% and an odds ratio of 15.64 (p = 0.013) in multivariate analysis. However, when the catheter was sufficiently inserted parallel to the brain stem using navigation, the survival was relatively well maintained (1,995 to 2,547 days). CONCLUSIONS: The stability of MVPS with Y was similar to that of single VPSs. However, the malfunction rate of the proximal catheter inserted at the fourth ventricle in the Y-connection was higher than that at other locations. The transcerebellar vertical approach or transtentorial approach parallel to the brain stem may decrease the malfunction rate.

Combined unilateral coronal-lambdoid suture synostosis: surgical outcome of suturectomy and postoperative helmet therapy.

INTRODUCTION: Nonsyndromic, multi-suture craniosynostosis is not common, especially those involving unilateral coronal and lambdoid sutures. Based on the experience on 6 cases, we analyzed the skull morphology of combined unilateral coronal-lambdoid suture synostosis and evaluated the surgical outcome of suturectomy. METHODS: Patients who underwent an operation for craniosynostosis in Seoul National University Children's Hospital from 2010 to 2018 were reviewed. For qualitative analysis of the surgical outcome, five typical morphologic characteristics (ipsilateral superior orbital rim deviation, deviation of the nasal ridge, ipsilateral frontal flattening, contralateral parietal bulging, ipsilateral occipitomastoid bulging) in unilateral coronal-lambdoid suture synostosis were evaluated based on medical photos, plain skull radiographs, and CT scans. For quantitative analysis, three parameters (nasal root deviation, orbital asymmetry, posterior skull base deviation) were measured. RESULTS: Among 316 patients with craniosynostosis, 41 patients had nonsyndromic, multi-suture synostosis. There were 6 unilateral coronal-lambdoid suture synostosis patients who were all treated with suturectomy. Qualitative evaluation of the postoperative outcome revealed that the nasal root and orbital rim deviations and the contralateral occipitomastoid bulging showed satisfactory improvements. However, ipsilateral frontal flattening and contralateral parietal bulging were improved but still present in most cases. Quantitative, craniometric analysis supported the qualitative outcomes. The nasal ridge deviation angle was corrected from 7.04 to 1.79 degrees. The posterior skull base deviation angle improved from 6.29 to 3.55 degrees. CONCLUSION: Unilateral coronal-lambdoid suture synostosis suturectomy followed by helmet therapy resulted in favorable outcomes, although the correction of frontal flattening was less satisfactory than the other measures. Considering the minimal invasiveness of the treatment, suturectomy may be a viable option for these patients.

A boy with a congenital cerebellar mass.

PURPOSE: Tumorigenesis of medulloblastoma is believed to be associated with granule cell progenitor neurogenesis of the cerebellum. Nevertheless, congenital medulloblastomas are rarely found. Here, we report a case of congenital medulloblastoma that showed spontaneous albeit transient regression. METHODS: A one-month-old baby presented with abnormal antenatal and postnatal imaging findings. Upon ultrasonography at 26 weeks of gestational age, Dandy-Walker malformation with vermian hypoplasia and cystic change was suspected. Brain MRI at 1 week after birth revealed gadolinium-enhancing lesions in the cerebellum with apparent infiltrative features along the cerebellar folia accompanied by three independent cysts in the upper and inferolateral sides of the lesion. Serial MRIs taken up to 5 months of age showed a decrease in the size and extent of enhancing solid portions. The baby did not show any abnormal signs or developmental delay. MRI at the age of 7 months showed enlargement of the lesion, and surgery was performed. RESULTS: The lesion was diagnosed as medulloblastoma with histologically extensive nodularity (MBEN), genetically SHH-activated and TP53-wildtype. CONCLUSION: This case provides an unusual chance of observing an early phase of medulloblastoma development and raises a suspicion that medulloblastoma may initiate itself very early in cerebellar organogenesis and progress later at a certain time of postnatal development.

Extracellular vesicle-associated miR-135b and -135a regulate stemness in Group 4 medulloblastoma cells by targeting angiomotin-like 2.

BACKGROUND: Extracellular vesicles (EVs) secreted by tumours, including exosomes, are important factors that regulate cell-cell interactions in oncogenesis. Although EV studies are ongoing, the biological understanding of EV-miRNAs derived from brain tumour spheroid-forming cells (BTSCs) of medulloblastoma is poor. PURPOSES: We explored the specific cellular miRNAs and EV-miRNAs in medulloblastoma BTSCs to determine their potential biological function. METHODS: Bulk tumor cells (BTCs) and BTSCs were cultured under different conditions from medulloblastoma tissues (N = 10). RESULTS: Twenty-four miRNAs were simultaneously increased in both cells and EVs derived from BTSCs in comparison to BTCs. After inhibition of miR-135b or miR135a which were the most significantly increased in BTSCs, cell viability, self-renewal and stem cell marker expression decreased remarkably. Through integrated analysis of mRNAs and miRNAs data, we found that angiomotin-like 2 (AMOTL2), which was significantly decreased, was targeted by both miR-135b and miR-135a. STAT6 and GPX8 were targeted only by miR-135a. Importantly, low expression of AMOTL2 was significantly associated with overall poor survival in paediatric Group 3 and Group 4 medulloblastoma patients. CONCLUSION: Our results indicated that inhibition of miR-135b or miR-135a leads to suppress stemness of BTSC through modulation of AMOTL2.

Treatment outcome and long-term follow-up of central nervous system germ cell tumor using upfront chemotherapy with subsequent photon or proton radiation therapy: a single tertiary center experience of 127 patients.

BACKGROUND: Central nervous system germ cell tumors (CNS GCTs) are a heterogeneous group of brain tumors, which are more common in Asian countries. There have been different therapeutic strategies in treating germinoma and non-germinomatous germ cell tumors (NGGCT), depending on prognosis. Moreover, long-term follow up should be emphasized due to higher late complication rates. Here, we investigated long-term outcomes and complication profiles of 127 CNS GCT patients who received uniform upfront chemotherapy. METHODS: We retrospectively evaluated outcomes of CNS GCT patients treated in Seoul National University Children's Hospital from August 2004 to April 2019. Patients were classified as low risk (LR) or high risk (HR) based on pathologic diagnosis and tumor markers. Most patients received upfront systemic chemotherapy with carboplatin, cyclophosphamide, etoposide, and/or bleomycin, followed by either proton or photon radiation therapy according to patients' choice. RESULTS: The median age at diagnosis was 11.9 (range, 3.8-25.1) years, and 54.3% of patients were LR. Photon and proton radiation therapy were administered to 73.2 and 25.2% of patients, respectively. In both LR and HR groups, there were no significant differences in survival between photon and proton radiation therapy. The 10-year relapse incidences were 9.3 and 5.6% in the LR and HR groups, respectively. All recurrences, except one, were local relapse. Six secondary malignancies occurred; the 10-year incidences of secondary malignancy were 2.2 and 7.6% in the LR and HR groups, respectively. The 10-year overall survival rates were 98.3 ± 1.7 and 91.8 ± 3.9% in the LR and HR groups, respectively. In a subgroup analysis of HR group, pathologically diagnosed NGGCT patients (n = 20) showed worse 10-year EFS (65.9 ± 11.9%, p < 0.001) and OS (77.9 ± 9.8%, p = 0.024) rates compared to other HR patients who were not pathologically diagnosed or were confirmed as germinoma with elevated tumor markers. All mortalities were related to disease progression or secondary malignancy. CONCLUSION: The strategy of treating CNS GCTs with upfront chemotherapy according to risk groups resulted in good clinical outcomes and acceptable relapse incidence. However, further modification in the definition of the HR group is needed to reduce long-term complications.

Do junctional neural tube defect and segmental spinal dysgenesis have the same pathoembryological background?

INTRODUCTION: Junctional neural tube defect (JNTD) is a recently introduced form of congenital spinal dysraphism that is characterized by functional disconnection between the primary and secondary neural tubes. The upper and lower cords appeared to be connected by a non-functioning band-like structure. JNTD is suspected to arise from a developmental error not corresponding to either primary or secondary neurulation, but rather between the two neurulation processes. On the other hand, segmental spinal dysgenesis (SSD) is an older entity of spinal anomalies in which a segment of the spine and spinal cord does not develop properly. The anomaly had been noted for the bony abnormality, as it is the most prominent feature. Based on the recent encounter of two cases resembling both entities, we sought the possibility that the two diseases may have the same pathoembryogenesis. METHODS AND RESULTS: Based on the impression that the two entities share important features, we compared the details of the two anomalies. First, our two recently encountered cases of JNTD were described. Second, previous reports of SSD were comprehensively reviewed. The two cases had the essential anomaly of the neural structures satisfying the definition of JNTD, as well as the elaborate spinal deformity as seen in SSD. In the previous literature on SSD, it was recognized that in addition to the bone anomaly, disconnected spinal cord was present. Hence, the two entities seem to have many similar clinical and neuroimaging features. The dysgenic spinal level is similar, and the disconnection between the primary and secondary neural tubes is found in the two diseases. The two neural tubes are connected by a band-like structure, with severe stenosis of the spinal canal at the level of the band. Both entities show segmental anomalies of the vertebrae in the thoracolumbar region, especially in the posterior element. Although the extent of shared features seems high, the previously suggested hypothetical pathoembryogenesis of SSD did not involve the process of junctional neurulation. We suggest that SSD shares the same origin as JNTD, and the bony abnormality may be a secondary phenomenon to the core error during neural tube development. CONCLUSIONS: We propose that JNTD and SSD may be the same entity, originating from an error during junctional neurulation. As there is controversy regarding the treatment strategy for both entities, unified accumulation of clinical experience and analysis may help improve the management of patients.

Long-Term Outcomes of Indirect Bypass for 629 Children With Moyamoya Disease: Longitudinal and Cross-Sectional Analysis.

Background and Purpose- In pediatric moyamoya disease, there are few reports on the efficacy of surgical intervention for stroke prevention. We evaluated the long-term outcomes of indirect bypass surgery on a relatively large number of children with moyamoya disease in a single center. Methods- From August 1988 to December 2012, 772 children underwent indirect bypass surgery. This study included 629 patients who were followed up for >5 years, excluding patients with moyamoya syndrome. The mean clinical follow-up duration was 12 years (range, 5-29 years). Cross-sectional analysis was performed based on either Karnofsky Performance Scale or Lansky Play Performance Scale to evaluate overall clinical outcomes and factors associated with unfavorable outcomes. To analyze the longitudinal effect of surgery, the annual risk of symptomatic infarction or hemorrhage on the operated hemisphere after indirect bypass surgery was calculated with a person-year method, and the event-free survival rate was evaluated using the Kaplan-Meier method. Results- The overall clinical outcome was favorable in 95% of the patients. The annual risks of symptomatic infarction and hemorrhage on the operated hemispheres were 0.08% and 0.04%, respectively. Furthermore, the 10-year event-free survival rates for symptomatic infarction and hemorrhage were 99.2% and 99.8%. Conclusions- Indirect bypass surgery could provide satisfactory long-term improvement in overall clinical outcome and prevention of recurrent stroke in children with moyamoya disease.