Post-traumatic Transient Neurological Dysfunction: A Proposal for Pathophysiology.

Unexplained neurological deterioration is occasionally observed in patients with traumatic brain injuries (TBIs). We aimed to describe the clinical features of post-traumatic transient neurological dysfunction and provide new insight into its pathophysiology. We retrospectively collected data from patients with focal neurological deterioration of unknown origin during hospitalization for acute TBI for 48 consecutive months. Brain imaging, including computed tomography, diffusion-weighted imaging and perfusion-weighted imaging, and electroencephalography were conducted during the episodes. Fourteen (2.0%) patients experienced unexplained focal neurological deterioration among 713 patients who were admitted for traumatic intracranial hemorrhage during the study period. Aphasia was the predominant symptom in all patients, and hemiparesis or hemianopia was accompanied in three patients. These symptoms developed within 14 days after trauma. Structural imaging did not show any significant interval change, and electroencephalography showed persistent arrhythmic slowing in the corresponding hemisphere in most patients. Perfusion imaging revealed increased cerebral blood flow in the symptomatic hemisphere. Surgical intervention and anti-seizure medications were ineffective in abolishing the symptoms. The symptoms disappeared spontaneously after 4 h to 1 month. Transient neurological dysfunction (TND) can occur during the acute phase of TBI. Although TND may last longer than a typical transient ischemic attack or seizure, it eventually resolves regardless of treatment. Based on our observation, we postulate that this is a manifestation of spreading depolarization occurring in the injured brain, which is analogous to migraine aura.

Neurocognitive outcomes and associated clinical factors 5 years after surgery in children with craniosynostosis.

OBJECTIVE: Craniosynostosis involves early closure of one or more sutures, which is known to limit normal cranium growth and interfere with normal brain development. Various surgical methods are used, ranging from minimally invasive strip craniectomy to more extensive whole-vault cranioplasty. This study aimed to evaluate neurocognitive outcomes 5 years after surgical treatment in children with craniosynostosis and to evaluate relevant clinical factors. METHODS: After exclusion of genetically confirmed syndromic craniosynostosis patients, a retrospective review was conducted on 112 nonsyndromic craniosynostosis patients who underwent surgical treatment and follow-up neurocognitive assessment. Ninety-seven patients underwent strip craniectomy with postoperative orthotic helmet therapy, and 15 received other surgical treatment: 4 with distraction osteotomy and 11 with craniofacial reconstruction. Neurocognitive assessment using the Korean Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (K-WPPSI-IV), was performed 5 years postoperatively. Clinical factors were assessed regarding neurocognitive outcomes. RESULTS: The mean age at surgery was significantly younger in the strip craniectomy group (strip craniectomy 4.6 months vs other surgical treatment 18.6 months, p < 0.01). Patients with 2 or more sutures involved were more likely to receive more extensive surgical treatment (16.5% in the strip craniectomy group vs 53.8% in the other group, p < 0.01). Four (3.5%) patients who showed evidence of increased intracranial pressure (ICP) also underwent more extensive surgical treatment. Multivariable linear regression revealed a significant correlation of age at neurocognitive testing (-3.18, 95% CI -5.95 to -0.40, p = 0.02), increased ICP (-34.73, 95% CI -51.04 to -18.41, p < 0.01), and the level of maternal education (6.11, 95% CI 1.01-11.20, p = 0.02) with the Full-Scale Intelligence Quotient (FSIQ). Age at surgery, involvement of 2 or more sutures, and type of operation demonstrated no correlation with FSIQ. Among the 97 patients who underwent strip craniectomy, the FSIQ ranged from mean ± SD 100.2 ± 10.2 (bicoronal) to 110.1 ± 12.7 (lambdoid), and there was no significant difference between the suture groups (p = 0.41). The 5 index scores were all within average ranges based on their age norms. CONCLUSIONS: Age at neurocognitive assessment, increased ICP, and maternal education level showed significant correlations with the neurocognitive function of craniosynostosis patients. Although children with craniosynostosis exhibited favorable 5-year postoperative neurocognitive outcomes across various synostosis sutures, longer follow-up is needed to reveal the incidence of neurocognitive dysfunction in these patients.

Clinical Features and Treatment of Pediatric Cerebral Cavernous Malformations.

Cerebral cavernous malformation (CCM) is a vascular anomaly commonly found in children and young adults. Common clinical presentations of pediatric patients with CCMs include headache, focal neurological deficits, and seizures. Approximately 40% of pediatric patients are asymptomatic. Understanding the natural history of CCM is crucial and hemorrhagic rates are higher in patients with an initial hemorrhagic presentation, whereas it is low in asymptomatic patients. There is a phenomenon known as temporal clustering in which a higher frequency of symptomatic hemorrhages occurs within a few years following the initial hemorrhagic event. Surgical resection remains the mainstay of treatment for pediatric CCMs. Excision of a hemosiderin-laden rim is controversial regarding its impact on epilepsy outcomes. Stereotactic radiosurgery is an alternative treatment, especially for deepseated CCMs, but its true efficacy needs to be verified in a clinical trial.

Measurement of the intersiphon distance for normal skull base development and estimation of the surgical window for the endoscopic transtuberculum approach in children.

OBJECTIVE: Due to the underdeveloped skull base in children, it is crucial to predict whether a sufficient surgical window for an endoscopic endonasal approach can be achieved. This study aimed to analyze the presumed surgical window through measurement of the intersiphon distance (ISD) and the planum-sella height (PSH) on the basis of age and its correlation with the actual surgical window for the endoscopic transtuberculum approach. METHODS: Twenty patients of each age from 3 to 18 years were included as the normal skull base population. ISD and PSH were measured and compared among consecutive ages. Additionally, 42 children with craniopharyngiomas or Rathke's cleft cysts who underwent treatment via the endoscopic transtuberculum approach were included. ISD and PSH were measured on preoperative images and then correlated with the dimensions of the surgical window on postoperative CT scans. The intraoperative endoscopic view was classified as narrow, intermediate, or wide based on operative photographs or videos, and relevant clinical factors were analyzed. RESULTS: In the normal skull base population, both ISD and the estimated area of the surgical window increased with age, particularly at 8 and 11 years old. On the other hand, PSH did not show an incremental pattern with age. Among the 42 children who underwent surgery, 24 had craniopharyngioma and 18 had Rathke's cleft cysts. ISD showed the strongest correlation with the actual area of the surgical window [r(40) = 0.69, p < 0.001] rather than with age or PSH. The visual grade of the intraoperative endoscopic view was narrow in 17 patients, intermediate in 21, and wide in 4. Preoperative ISD was 14.58 ± 1.29 mm in the narrow group, 16.13 ± 2.30 mm in the intermediate group, and 18.09 ± 3.43 mm in the wide group (p < 0.01). There were no differences in terms of extent of resection (p = 0.41); however, 2 patients in the narrow group had postoperative complications. CONCLUSIONS: Normal skull base development exhibited age-related growth. However, in children with suprasellar lesions, the measurement of the ISD showed a better correlation than age for predicting the surgical window for the endoscopic transtuberculum approach. Children with a small ISD should be approached with caution due to the limited surgical window.

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.

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.

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.

Survival and Malignant Transformation of Pineal Parenchymal Tumors: A 30-Year Retrospective Analysis in a Single-Institution.

BACKGROUND: This study aims to elucidate clinical features, therapeutic strategies, and prognosis of pineal parenchymal tumors (PPT) by analyzing a 30-year dataset of a single institution. METHODS: We reviewed data from 43 patients diagnosed with PPT at Seoul National University Hospital between 1990 and 2020. We performed survival analyses and assessed prognostic factors. RESULTS: The cohort included 10 patients with pineocytoma (PC), 13 with pineal parenchymal tumor of intermediate differentiation (PPTID), and 20 with pineoblastoma (PB). Most patients presented with hydrocephalus at diagnosis. Most patients underwent an endoscopic third ventriculostomy and biopsy, with some undergoing additional resection after diagnosis confirmation. Radiotherapy was administered with a high prevalence of gamma knife radiosurgery for PC and PPTID, and craniospinal irradiation for PB. Chemotherapy was essential in the treatment of grade 3 PPTID and PB. The 5-year progression-free survival rates for PC, grade 2 PPTID, grade 3 PPTID, and PB were 100%, 83.3%, 0%, and 40%, respectively, and the 5-year overall survival rates were 100%, 100%, 40%, and 55%, respectively. High-grade tumor histology was associated with lower survival rates. Significant prognostic factors varied among tumor types, with World Health Organization (WHO) grade and leptomeningeal seeding (LMS) for PPTID, and the extent of resection and LMS for PB. Three patients experienced malignant transformations. CONCLUSION: This study underscores the prognostic significance of WHO grades in PPT. It is necessary to provide specific treatment according to tumor grade. Grade 3 PPTID showed a poor prognosis. Potential LMS and malignant transformations necessitate aggressive multimodal treatment and close-interval screening.

Methylation-based Subclassifications of Embryonal Tumor with Multilayered Rosettes in Not Just Pediatric Brains.

The aim of this study is to investigate the genetic profiles and methylation-based classifications of Embryonal tumor with multilayered rosettes (ETMR), with a specific focus on differentiating between C19MC amplified and C19MC-not amplified groups, including cases with DICER1 mutations. To achieve this, next-generation sequencing using a targeted gene panel for brain tumors and methylation class studies using the Epic850K microarray were performed to identify tumor subclasses and their clinicopathological characteristics. The study cohort consisted of four patients, including 3 children (a 4-months/F, a 9-months/M, and a 2 y/F), and one adult (a 30 y/Male). All three tumors in the pediatric patients originated in the posterior fossa and exhibited TTYH1:C19MC fusion and C19MC amplification. The fourth case in the adult patient involved the cerebellopontine angle with biallelic DICER1 mutation. Histopathological examination revealed typical embryonal features characterized by multilayered rosettes and abundant neuropils in all cases, while the DICER1-mutant ETMR also displayed cartilage islands in addition to the classic ETMR pathology. All four tumors showed positive staining for LIN28A. The t-SNE clustering analysis demonstrated that the first three cases clustered with known subtypes of ETMR, specifically C19MC amplified, while the fourth case clustered separately to non-C19MC amplified subclass. During the follow-up period of 6~12 months, leptomeningeal dissemination of the tumor occurred in all patients. Considering the older age of onset in DICER1-mutant ETMR, genetic counseling should be recommended due to the association of DICER1 mutations with germline and second-hit somatic mutations in cancer.

Neuroepithelial tumor with EWSR1::PATZ1 fusion: A literature review.

We present the clinicopathological and molecular genetic characteristics of a neuroepithelial tumor (NET), EWSR1::PATZ1 fusion-positive with a literature review. This fusion has recently been discovered in rare central nervous system tumors and soft tissue sarcomas and was not included in the fifth edition of the WHO classifications. We identified this fusion in 2 NETs. The first case involved a 7-year-old girl and the second case occurred in a 53-year-old man; both presented with headaches and vomiting. The pediatric case initially showed an intermediate grade of the tumor, but upon recurrences, it transformed into a high-grade tumor with 2 relapses in 8.3 years. This case exhibited high mitotic activity (20/10 high-power fields), and a high Ki-67 index (21%). The TERT promoter (TERTp) mutation was present in both initial and recurrent tumors. In contrast, the adult case was a low-grade tumor with no mitotic activity or recurrence over 13.5 months after subtotal resection and gamma knife surgery. Interestingly, the pediatric case demonstrated a longer survival time compared to conventional glioblastoma. The TERTp mutation, similar to being a molecular signature in adult-type glioblastoma, could also be an indicator of high-grade behavior in PATZ1 fusion NET.

Choroid Plexus Hyperplasia : Report of Two Cases with Unique Radiologic Findings.

Choroid plexus hyperplasia (CPH), also known as diffuse villous hyperplasia of choroid plexus, is a rare condition characterized by excessive production of cerebrospinal fluid (CSF), resulting in hydrocephalus. Diagnosing CPH can be challenging due to the absence of clear imaging criteria for choroid plexus hypertrophy and the inability to assess CSF production non-invasively. As a result, many CPH patients are initially treated with a ventriculoperitoneal (VP) shunt, but subsequently require additional surgical intervention due to intractable ascites. In our study, we encountered two CPH patients who presented with significantly enlarged subarachnoid spaces, reduced parenchymal volume, and prominent choroid plexus. Initially, we treated these patients with a VP shunt, but eventually opted for endoscopic choroid plexus cauterization (CPC) to address the intractable ascites. Following the treatment with endoscopic CPC, we observed a gradual reduction in subarachnoid spaces and an increase in parenchymal volume. In cases where bilateral prominent choroid plexus, markedly enlarged subarachnoid spaces, and cortical atrophy are present, CPH should be suspected. In these cases, considering initial treatment with combined endoscopic CPC and shunt may help minimize the need for multiple surgical interventions.

Growth patterns of young achondroplasia patients in Korea and predictability of neurosurgical procedures.

BACKGROUND: Achondroplasia is an autosomal dominant disorder mainly affecting bony growth, typically resulting in markedly short stature. From a neurosurgical viewpoint, patients sometimes develop spinal cord compression at the narrowed foramen magnum and hydrocephalus. This study aims to construct growth references for height, weight, and head circumference (HC) of young achondroplasia patients in Korea and to evaluate the predictability of the necessity and timing of neurosurgical procedures through growth patterns. METHODS: Growth data were collected from achondroplasia patients who visited our institution between January 2002 and August 2022. First, we constructed percentile growth curves of height, weight, and HC for the patients under 3 years of age with the generalized additive model for location, scale, and shape (GAMLSS). Second, the growth patterns of the patients with hydrocephalus who underwent neurosurgical procedures such as foramen magnum decompression (FMD) and ventriculoperitoneal (VP) shunt were analyzed. RESULTS: There were 125 achondroplasia patients, including 67 males and 58 females. Among 125 patients, 46 underwent FMD, and 5 underwent VP shunt. As short stature and macrocephaly were typical characteristics of achondroplasia, the height of achondroplasia was lower than that of the general population, and HC in achondroplasia showed accelerated growth postnatally. There were no significant changes in HC in hydrocephalus patients before they underwent neurosurgical procedures. The influence of hydrocephalus on the growth patterns of HC in achondroplasia seemed insignificant. CONCLUSION: Growth references for height, weight, and HC in young achondroplasia patients were constructed. It is the first report of growth patterns of achondroplasia in Korea. Unlike other pediatric patients, the diagnosis of hydrocephalus and the necessity of neurosurgical procedures are hard to be predicted with HC in achondroplasia. Neuroimaging should be considered for achondroplasia patients with neurological symptoms.

Identification of bacterial pathogens in brain abscesses by metagenomic approach using nanopore 16S amplicon sequencing.

Brain abscess is medically challenging. In this study, we applied nanopore sequencing for 16S rRNA analysis and investigated its efficacy and diagnostic value for patients with brain abscesses. Genomic DNA was extracted from the pus samples (n = 27) of brain abscess, and 16S rRNA genes were amplified by PCR. Sequencing libraries were generated using a rapid barcoding kit, and the generated reads were analyzed using the EPI2ME16S workflow. A conventional culture study was performed. More sensitive identification of pathogens was made by 16S sequencing, faster than the culture study. The proportion of anaerobic bacteria identified by 16S sequencing was higher (75%) than that obtained by culturing (32%). Polymicrobial infections were identified in 10 cases (40%) by 16S sequencing, while the culture study identified multiple bacteria in only 2 cases (8%). 16S sequencing was useful for identifying the composition of polymicrobial infections, including rare pathogens, and for the initial diagnosis of space-occupying lesions.

Surgical indication of pediatric Rathke's cleft cyst based on a 20-year retrospective cohort.

OBJECTIVE: Rathke's cleft cyst (RCC) is the most commonly encountered pituitary incidentaloma in children. Because RCC is not frequently diagnosed in children, there are few reports on pediatric RCCs. The natural course of the disease and appropriate treatments are still obscure. The present study aimed to elucidate the natural history and surgical indications of RCCs in children. METHODS: The authors retrospectively reviewed the clinical presentations, imaging features, ophthalmological evaluations, endocrine evaluations, and surgical outcomes of pediatric RCCs at a single institution from January 2000 to October 2022. Clinical outcomes between the surgery and observation groups were compared. RESULTS: Among 93 patients, there were 41 patients in the surgery group and 52 patients in the observation group. The mean age at diagnosis was 10.9 years, and the mean follow-up period was 5.6 years. Headache fully or partially improved after surgery (86.2%), but the rate of improvement was not different from that of the observation group (70.0%). Ophthalmological abnormalities were effectively improved by surgical treatment (93.3%). Both the improvement and deterioration rates of endocrine abnormalities were significantly higher in the surgery group (p = 0.026 and p < 0.001, respectively), but the deterioration rate (43.9%) was higher than the improvement rate (14.6%). In the surgery group, the recurrence rate was 17.1% and the reoperation rate was 4.9%. Compared with total cyst wall resection, cyst fenestration with partial wall resection was associated with a higher recurrence rate (26.9%, p = 0.035) but a lower rate of endocrine abnormalities (30.8%, p = 0.049). CONCLUSIONS: Pediatric RCCs of ≥ 10 mm in size were analyzed. Ophthalmological abnormalities are the major surgical indications for pediatric RCCs. Headache and partial endocrine abnormalities may be improved with surgery, but they are not absolute indications for surgery. Cyst fenestration with partial wall resection via an endoscopic endonasal approach is the most recommended surgical method. Follow-up is essential to monitor for the occurrence of visual field defects and the recurrence of cysts.

Spontaneous recovery of underlying bony erosion following surgical removal of craniofacial dermoid cysts in periatric patients: A prospective study.

This study aimed to evaluate the spontaneous recovery of bone deformity after surgical excision of craniofacial dermoid cysts in pediatrics. Pediatric patients who underwent excision of a dermoid cyst were included in the study. A prospective analysis was conducted to evaluate the amount of bone recovery by comparing the depth of bony concavity in the preoperative and postoperative (6 months) ultrasonography. In 145 of 187 patients with preoperative imaging available, the mean size of dermoid cysts was 1.4 cm3 (range, 0.1 to 9.5), and 41.4% (60/145 cases) showed cranial bone depression. In the comparison of preoperative and postoperative ultrasonography of 30 patients, the mean depth of bony cavity decreased significantly from 4.0 to 0.9 mm (p<0.001) after a mean of 6.7 months postoperatively. There was 13.3% (4/30) of mild (≤2.0 mm), 40.0% (12/30) of moderate (>2.0 to ≤4.0 mm), and 46.7% (14/30) of severe (>4.0 mm) depression, and the concavity depth significantly decreased in all groups (p = 0.028, mild; p<0.001, moderate; p<0.001 severe). Within the limitations of the study it seems that significant recovery of cranial bone depression does take place within 6 months after excision of craniofacial dermoid cysts in pediatric patients, saving the need for immediate reconstruction.

Long-Term Surgical Outcome of Indirect Bypass Surgery in Young Children With Moyamoya Disease.

BACKGROUND: The prognosis of moyamoya disease (MMD) in young children (younger than 4 years) is worse than that of older adults. The effectiveness of surgery is still inconclusive. OBJECTIVE: To evaluate long-term outcomes after indirect bypass in young children with MMD. METHODS: A total of 1417 MMD children underwent indirect bypass from August 1988 to October 2020. This study included 135 patients who were younger than 4 years at the time of surgery. The clinical features and surgical outcomes of these patients were assessed. We analyzed the long-term outcome of 102 children who were followed up for more than 5 years (mean: 18.8 years, range: 5-27.3 years). Cross-sectional analysis was performed to evaluate overall outcomes based on the Lansky Play Performance Scale (LPS). The annual risk of symptomatic stroke after 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 (LPS ≥ 80) in 88% of the patients. The overall postoperative adverse event rate was 15%, including 1 death. At the last follow-up, 86% of patients who had seizures at diagnosis were seizure-free. During the follow-up, there were 3 symptomatic infarctions on the operated hemisphere (postoperative 3, 3, and 10 months each). There was no hemorrhagic event. The annual infarction rate was 0.16% per person-year. The 20-year event-free survival rates for symptomatic infarction were 97%. CONCLUSION: Indirect bypass could provide a satisfactory long-term outcome and prevent recurrent stroke in young children with MMD.

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.

Cyclin-Dependent Kinase Inhibitor 2A is a Key Regulator of Cell Cycle Arrest and Senescence in Endothelial Colony-Forming Cells in Moyamoya Disease.

OBJECTIVE: Endothelial colony-forming cells (ECFCs) have been reported to play an important role in the pathogenesis of moyamoya disease (MMD). We have previously observed stagnant growth in MMD ECFCs with functional impairment of tubule formation. We aimed to verify the key regulators and related signaling pathways involved in the functional defects of MMD ECFCs. METHODS: ECFCs were cultured from peripheral blood mononuclear cells of healthy volunteers (normal) and MMD patients. Low-density lipoproteins uptake, flow cytometry, high content screening, senescence-associated ß-galactosidase, immunofluorescence, cell cycle, tubule formation, microarray, real-time quantitative polymerase chain reaction, small interfering RNA transfection, and western blot analyses were performed. RESULTS: The acquisition of cells that can be cultured for a long time with the characteristics of late ECFCs was significantly lower in the MMD patients than the normal. Importantly, the MMD ECFCs showed decreased cellular proliferation with G1 cell cycle arrest and cellular senescence compared to the normal ECFCs. A pathway enrichment analysis demonstrated that the cell cycle pathway was the major enriched pathway, which is consistent with the results of the functional analysis of ECFCs. Among the genes associated with the cell cycle, cyclin-dependent kinase inhibitor 2A (CDKN2A) showed the highest expression in MMD ECFCs. Knockdown of CDKN2A in MMD ECFCs enhanced proliferation by reducing G1 cell cycle arrest and inhibiting senescence through the regulation of CDK4 and phospho retinoblastoma protein. CONCLUSION: Our study suggests that CDKN2A plays an important role in the growth retardation of MMD ECFCs by inducing cell cycle arrest and senescence.

Comparison of Bifrontal Craniotomy and Multiple Burr Hole Encephalogaleoperiosteal-Synangiosis for Pediatric Moyamoya Disease: An Experience of 346 Patients.

BACKGROUND AND OBJECTIVES: Moyamoya disease (MMD) is a steno-occlusive disease treated with revascularization surgery. Craniotomy and multiple burr hole encephalogaleoperiosteal-synangiosis (EGPS) are used for revascularization of the anterior cerebral artery territory. The aim of this study was to compare the clinical outcome between the 2 surgical methods in pediatric patients with MMD. METHODS: A retrospective review of patients with MMD who underwent bifrontal indirect bypass surgery was performed. Clinical features, perioperative data, and angiographic, perfusion, and functional outcomes were compared between the 2 groups. Propensity score matching was performed to compare the perioperative characteristics and clinical outcomes. RESULTS: A total of 346 patients were included in this study, 111 patients underwent bifrontal craniotomy EGPS, and 235 patients had bifrontal multiple burr hole EGPS. An insignificant higher rate of postoperative infarction (11.7% vs 5.5%, P = .072) and more postoperative hemorrhage occurred in the craniotomy EGPS group (3.6% vs 0%, P = .004). Of the 83 patients selected with propensity score matching for each group, the duration of operation was shorter ( P < .001) and the amount of intraoperative bleeding was significantly less in the multiple burr hole EGPS group ( P = .008). There was no difference in clinical outcomes between the 2 groups. CONCLUSION: Bifrontal multiple burr hole EGPS has benefits over craniotomy with shorter surgical time, less intraoperative bleeding, fewer postoperative complications, and comparable perfusion and functional outcomes. Multiple burr hole EGPS is a safe and effective method that might be considered for revascularization of the anterior cerebral artery territory in pediatric patients with MMD.

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.