Large language models (LLMs) are rapidly transforming healthcare, yet their implications for pediatric neurosurgery remain underexplored. This narrative review interprets LLM evolution through a neuroscientific lens familiar to pediatric neurosurgeons. We trace the parallel development of LLMs and the human brain : architecture evolving from sequential processing to attention mechanisms mirrors prefrontal cortex maturation; training stages parallel synaptic exuberance, adolescent pruning, and socialization; reasoning capabilities emerge through chain-of-thought prompting and reinforcement learning, analogous to deliberate cognitive processing. We then examine capabilities current LLMs lack but would require for artificial general intelligence (AGI)-continual learning, multimodal perception, self-awareness, world models, and physical embodiment-mapping each to corresponding neural functions. Using a representative case of pediatric medulloblastoma, we illustrate how these technologies will reshape clinical practice, surgery, research, and education. Current frontier models deliver excellent medical performance with multimodal reasoning at low cost, yet pediatric neurosurgery presents a "long-tail" challenge where rare conditions and reliance on expert consensus demand domain-specific augmentation. The emergence of agentic artificial intelligence (AI), physical AI, and autonomous research systems signals a shift from AI as advisory tool to executing partner. LLMs externalize intellectual labor at unprecedented scale, redefining physicians as "responsible interpreters" who orchestrate AI while retaining judgment, accountability, and ethical authority. In pediatric neurosurgery, this role uniquely integrates metacognitive and emotional dimensions beyond AI's reach within the child-caregiver-physician relationship, enabling human-centered care and empowering neurosurgeons to actively shape AI integration rather than merely adapt to it.

Neuroinflammation and cognitive impairment during the perioperative period significantly affect patient recovery, making them critical targets for therapeutic intervention. Recently, there has been growing interest in gut-derived exosomes (bacterial extracellular vesicles, BEVs) and their potential to modulate the central nervous system. The gut-brain axis, a vital pathway linking the gut to the central nervous system, offers a unique lens through which to explore the role of BEVs in nerve regeneration. This study investigates the biological properties and functions of BEVs during the perioperative period, focusing on their mechanisms in promoting post-anesthesia nerve recovery, including anti-inflammatory effects, neurotrophic support, and metabolic reprogramming. Additionally, the study explores potential BEV-based therapeutic approaches, current challenges in research, and future directions, aiming to provide novel insights and rationales for clinical application.

Generative artificial intelligence (AI) has emerged as a transformative tool for creating high-quality visual materials in medical research and education. In pediatric neurosurgery, where ethical and legal constraints limit the use of real patient photographs, AI-assisted illustrations offer significant potential. However, concerns regarding clinical accuracy, intellectual property, and the protection of vulnerable pediatric patients necessitate rigorous oversight. We present a human-in-the-loop workflow that integrates generative AI with vector-based digital editing to produce scientifically accurate and ethically grounded medical illustrations. We reviewed current AI usage policies from major medical journals, including the International Committee of Medical Journal Editors and the Journal of Korean Neurosurgical Society (JKNS). To demonstrate practical application, we developed illustrative examples for conditions such as sacral dimple, Crouzon syndrome, and Down syndrome using clinician-led sketches and AI-assisted refinement. Vector-based workflows facilitate the transformation of AI-generated raster drafts into editable, high-resolution graphics, allowing clinicians to correct "hallucinations" and ensure anatomical precision. While most journals prohibit listing AI as an author, they permit its use for conceptual figures provided there is transparent disclosure of the tools and prompts used. Our proposed workflow emphasizes that AI should function as a "constrained assistant" rather than an autonomous creator, ensuring that the final output remains non-identifiable and respectful of pediatric patients' dignity. Generative AI tools can significantly enhance visualization in pediatric neurosurgery when governed by strict ethical and technical safeguards. Adherence to journal policies and the maintenance of human-directed validation are essential to uphold scientific integrity and patient privacy in the era of AI-assisted publishing.

Pediatric neurosurgery increasingly utilizes precision medicine, but practitioners encounter challenges in translating complex data into individualized care. Digital twin (DT) bridges this gap by linking real-world data to a dynamic patient in-silico model, facilitating prediction and adaptive management as new data emerge. This narrative review explores the essential features of DTs, highlighting their relevance and associated risks in pediatric neurosurgery. The DT framework is structured around five components : the patient, a data connection, a patient-in-silico model, a clinician interface, and temporal synchronization. Foundational modeling approaches are summarized, spanning mechanistic simulations, artificial intelligence, and hybrid models that combine mechanistic structure with data-driven inference. Clinicaltranslation is framed around uncertainty and calibration, along with interpretability and detection of distribution shifts. Potential applications are organized by concrete clinical questions in epilepsy surgery, pediatric neuro-oncology, cerebrovascular disease, hydrocephalus, and craniosynostosis. A translational pathway is outlined that progresses from decision-oriented prototypes and retrospective validation to prospective evaluation and interventional studies within learning health systems, supported by robust governance and auditable workflows. With meticulous validation and cautious deployment tailored to pediatric populations, DTs may enhance transparency,testability, and shared decision-making in precision pediatric neurosurgery.

Objective : Aspiration thrombectomy is a widely adopted treatment for acute ischemic stroke due to large vessel occlusion. Among several technical factors, the diameter of the aspiration catheter plays a critical role in determining thrombus fixation, aspiration efficiency, and overall procedural success. This study aimed to investigate the biomechanical effects of a larger catheter diameter on thrombus behavior and vessel wall response during aspiration thrombectomy. Methods : Finite element analysis was employed to simulate aspiration using three clinically relevant aspiration catheters with different diameters. Thrombi of two lengths and two compositions, varying in red blood cell content, were modeled to reflect clinical variability. Mechanical outcomes, including thrombus deformation, internal stress distribution, and vessel wall loading, were analyzed under standardized aspiration pressure conditions. Results : 0.080- and 0.084-inch large-bore catheters produced greater thrombus deformation and internal stress than the 0.072-inch catheter, particularly in softer thrombi with higher red blood cell content. In both 3 and 5 mm thrombi with red blood cells, deformation increased by approximately 12.3% with the 0.084-inch catheter compared to the 0.072-inch catheter. These changes indicate improved clot engagement and aspiration efficiency, while vessel stress remained within physiological limits. This mechanical advantage is partly due to greater luminal occupancy, with the 0.084-inch catheter occupying 65.6% of the vessel lumen, about 14% more than the 0.072-inch catheter. Conclusion : Large-bore aspiration catheters can enhance thrombus fixation and aspiration performance without compromising vascular integrity. These findings support the broader clinical use of larger-bore catheters in patients with large artery occlusion, particularly in cases requiring strong clot engagement and efficient recanalization.

Objective : Epidural fibrosis (EF) is a major contributor to postoperative morbidity following laminectomy (LAM). This study investigated the antifibrotic, anti-inflammatory, and anti-angiogenic effects of nintedanib (NIN), a multi-tyrosine kinase inhibitor, in a rat model of post-LAM EF. Methods : Twenty-one male Wistar albino rats were assigned to three groups : control, LAM, and LAM + NIN. The LAM procedure was performed at the L3 level. NIN administration, following LAM, was administered orally at a dose of 50 mg/kg/day for 28 days. Histopathological evaluations included Hematoxylin & Eosin staining for dura mater thickness and fibroblast density, and Masson's trichrome staining for collagen deposition and adhesion grading. α-smooth muscle actin (α-SMA) expression was evaluated using immunohistochemistry and reverse transcription-quantitative polymerase chain reaction. Gene expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), vascular endothelial growth factor (VEGF), platelet-derived growth factor receptor (PDGFR), and transforming growth factor-β1 (TGF-β1) was quantified to characterize inflammatory, angiogenic, and fibrogenic responses. Statistical comparisons were conducted using one-way analysis of variance or Kruskal-Wallis tests with appropriate post hoc analyses. Results : The LAM group exhibited marked post-LAM changes, including increased dura mater thickness (8.20±0.23 vs. 3.93±0.08 ㎛ in controls, p<0.0001), elevated fibroblast density (p=0.0006), severe collagen deposition, and high-grade epidural adhesions (grade 3, p=0.0006). NIN treatment attenuated these alterations, reducing dura mater thickness (4.80±0.20 ㎛; p<0.0001 vs. LAM), fibroblast density (p<0.01), and adhesion grade (grade 1, p=0.0012). α-SMA immunoreactivity was high in LAM (grade 3, p<0.0001), whereas NIN significantly suppressed myofibroblast activation (grade 1, p=0.0012). NIN also significantly downregulated inflammatory mediators TNF-α (p<0.001) and IL-1β (p<0.001), as well as angiogenic markers VEGF (p<0.001) and PDGFR (p<0.001), and fibrogenic mediators TGF-β1 (p<0.001) and α-SMA (p<0.01). These findings indicate that NIN suppresses fibroblast activation, extracellular matrix accumulation, and myofibroblast differentiation, thereby limiting epidural adhesion and scar maturation. Conclusion : Nintedanib effectively mitigated epidural fibrosis after LAM through combined antifibrotic, anti-inflammatory, and anti-angiogenic actions. By improving the dural structure and reducing key molecules that contribute to scar formation, NIN shows significant promise as a treatment to prevent postoperative epidural adhesions. Future studies with extended follow-up may help clarify its clinical relevance.

Objective : Gamma knife radiosurgery (GKRS) is an established treatment for cerebral arteriovenous malformations (AVMs). However, incomplete obliteration after initial GKRS continues to pose a risk of hemorrhage. Although repeat GKRS is used as a salvage treatment, specific guidelines and safety profiles remain to be fully defined. By analyzing the clinical outcomes of repeat GKRS in 60 patients with incompletely obliterated AVMs, this study aims to test the hypothesis that optimizing treatment-related variables, particularly the timing of retreatment, may improve the safety and efficacy of repeat GKRS for residual AVMs. Methods : This retrospective study included 60 patients with AVMs who underwent repeat GKRS between 1992 and 2024. Clinical charts, radiologic imaging, and treatment parameters were analyzed to assess complete obliteration, hemorrhage after repeat GKRS, and adverse radiation effects (AREs). Kaplan-Meier survival analysis was performed to estimate obliteration and hemorrhage rates. Univariate and multivariate analyses were conducted to identify factors associated with complete obliteration, hemorrhage, and AREs. Results : Complete obliteration was achieved in 40 patients (66.7%). The actuarial obliteration rates were 1.7%, 22.5%, 53.5%, and 73.9% at 1, 3, 5, and 10 years, respectively. A target volume reduction rate >50% (p=0.004; hazard ratio [HR], 3.002; 95% confidence interval [CI], 1.414-6.374) and lower initial Spetzler-Martin (SM) grade (p=0.008; HR, 0.608; 95% CI, 0.420-0.879) were independently associated with complete obliteration. Six patients (10%) experienced hemorrhage after repeat GKRS, corresponding to an annual hemorrhage rate of 2.3%. AVMs located in the posterior fossa (p=0.005; HR, 80.958; 95% CI, 3.891-1684.629) and hemorrhage prior to repeat GKRS (p=0.020; HR, 19.075; 95% CI, 1.576-230.805) were independently associated with hemorrhage. Seven patients (11.7%) experienced AREs after repeat GKRS. Larger repeat target volume (p=0.042; odds ratio [OR], 3.170; 95% CI, 1.044-9.626) and a shorter interval of months between initial and repeat treatment (p=0.040; OR, 0.823; 95% CI, 0.683-0.991) were independently associated with AREs. Conclusion : Repeat GKRS for incompletely obliterated AVMs may provide favorable obliteration rates. Adequate volume response after initial GKRS and lower SM grades may predict successful complete obliteration. Patients with prior hemorrhage and AVMs located in the posterior fossa may be at greater risk of hemorrhage after repeat GKRS. Larger treatment volume and shorter intervals between initial and repeat GKRS were associated with AREs. Extending the interval between initial and repeat GKRS may reduce the risk of AREs and provide a safer approach for treating incompletely obliterated AVMs.

Objective : Osteopenic and osteoporotic vertebral compression fracture (OVCF) is a prevalent clinical problem, particularly in the elderly. Although the majority of compression fractures do not result in myelopathy and are managed nonoperatively, surgical intervention, including screw fixation, may be necessary in select cases of OVCF associated with myelopathy. This retrospective study compared the clinical outcomes, radiographic results, and complication rates between short-segment and long-segment screw fixation in patients with OVCF at the thoracolumbar junction (TLJ) and myelopathic symptoms due to a spinal cord-compressing lesion. Methods : A total of 48 patients with OVCFs at the TLJ and myelopathic symptoms, who underwent either short-segment (two-level, n=17) or long-segment (>2 levels, n=31) screw fixation were studied. Postoperative outcomes including clinical parameters, radiographic parameters, and incidence of complications were evaluated. Results : Postoperative improvement in Frankel scale was significantly greater in the short-segment versus long-segment fixation group (p=0.01). Long-segment fixation resulted in superior preservation of the postoperative correction angle (p<0.01). No difference in incidence of mechanical failure was demonstrated between the two groups (p=0.99). Conclusion : Short-segment fixation demonstrated greater postoperative neurological improvement and less invasiveness, whereas long-segment fixation was associated with superior preservation of the correction angle. It is also noteworthy that short-segment screw fixation is not predisposed to instrument failure compared to long-segment screw fixation. These findings suggest that short-segment screw fixation may be a viable option for many patients with OVCFs, depending on clinical condition.

Objective : Degenerative lumbar diseases accompanied by instability or severe foraminal stenosis are commonly treated with lumbar interbody fusion surgery. This study aimed to evaluate the clinical efficacy and safety of double-cage full endoscopic transforaminal lumbar interbody fusion (FE-TLIF) and posterior lumbar interbody fusion (PLIF) for the treatment of patients with severe degenerative lumbar disease. Methods : The clinical and radiological data of patients who underwent FE-TLIF using double cages or PLIF between March 2021 and February 2024 were retrospectively reviewed. Patients with single-level degenerative lumbar disease and Meyerding grade I spondylolisthesis who failed to respond to conservative treatment for 12 weeks were included. Patients with multilevel diseases, previous surgeries, or other spinal pathologies were excluded. Results : In total, 115 patients were included in the study (58 underwent FE-TLIF and 57 underwent PLIF). Baseline characteristics were comparable between the groups. The operation time and blood loss were significantly lower in the FE-TLIF group, and the cage height and angle were slightly greater. The FE-TLIF group showed faster postoperative pain relief, whereas the clinical outcomes at 6 and 12 months were similar between groups. At 12 months, the fusion rates and incidence of cage subsidence >2 mm did not differ significantly, even after adjustment. Both groups showed significant improvements in segmental and total lumbar lordosis and disc height, with slightly greater disc height restoration in the FE-TLIF group. The complication rates were low and comparable. Conclusion : Double-cage FE-TLIF achieved fusion and radiological outcomes comparable to those of PLIF, with the advantages of reduced blood loss, shorter operative time, and faster early pain relief. This technique may serve as a minimally invasive and effective alternative for treating single-level degenerative lumbar diseases.

Objective : This study investigated the cerebrospinal fluid (CSF) dynamic changes before and after cranioplasty using phase-contrast cine magnetic resonance imaging. Methods : We performed a prospective observational study in the patients who underwent cranioplasty in the neurosurgical department of our hospital between June 2022 and March 2025. We reviewed the changes of CSF flow parameters in the cerebral aqueduct before and after cranioplasty. Results : Totally, nine patients were enrolled, including five males and four females, with a mean age of 48.1 years. The time interval between decompressive craniectomy (DC) and cranioplasty was 119.1±45.1 days. The skull defect diameter and area were 10.7±2.2 cm and 94.4±34.6 cm², respectively. There are significant increases in forward flow volume (p=0.002), backward flow volume (p=0.002), net stroke volume (p=0.012), absolute stroke volume (p=0.001), mean flux (p=0.005), mean velocity (p=0.001), and peak velocity (p<0.001) after cranioplasty when compared with those parameters before cranioplasty. No significant correlation was observed between patient characteristics and the improvement magnitude of CSF flow parameters caused by cranioplasty. Conclusion : This study indicates that cranioplasty may have beneficial effects on CSF flow dynamics in the cerebral aqueduct after DC, which provides therapeutic potentials for complications related to CSF flow stagnancy after DC.

Objective : Deep brain stimulation (DBS) of the internal globus pallidus (GPi) represents the standard treatment for medically refractory dystonia, with clinical efficacy critically dependent on precise electrode placement. While robotic stereotactic systems promise enhanced targeting accuracy, comparative data for dystonia populations remain limited. To compare stereotactic accuracy and clinical outcomes of KYMERO robot-assisted versus conventional frame-based GPi-DBS in dystonia patients. Methods : A single-center, retrospective cohort study compared 35 patients (68 leads) who underwent KYMERO robot-assisted bilateral GPi-DBS (July 2023 to June 2025) with 42 historical controls receiving frame-based procedures (March 2019 to December 2020). All patients had medically refractory primary dystonia. Primary outcomes included stereotactic accuracy (radial and Euclidean error) and 6-month Burke-Fahn-Marsden dystonia rating scale (BFMDRS) motor improvement. Secondary outcomes encompassed response rates, complications, and procedural consistency. Results : KYMERO robot-assisted DBS achieved significantly superior targeting accuracy compared to frame-based procedures (mean radial error, 0.89±0.30 vs. 1.92±1.20 mm; p<0.001; euclidean error, 1.15±0.38 vs. 2.80±1.56 mm; p<0.001). The proportion of electrodes within 1.5 mm of target was higher in the KYMERO group (94.1% vs. 66.7%, p<0.001), with fewer targeting outliers exceeding 2 mm (2.9% vs. 23.8%). Clinical outcomes were equivalent between groups, with 6-month BFMDRS motor improvement of 66.9%±13.8% for KYMERO versus 64.7%±23.5% for frame-based procedures (p=0.614). Response rates (≥50% improvement) were 85.7% and 78.6%, respectively. Complication rates were low and comparable (5.7% vs. 9.5%). The KYMERO cohort demonstrated reduced outcome variability, suggesting enhanced procedural reproducibility. Conclusion : KYMERO robot-assisted GPi-DBS achieves significantly superior stereotactic accuracy compared to conventional framebased approaches while maintaining equivalent clinical efficacy and safety. The enhanced precision and reduced outcome variability support robotic assistance as a valuable advancement for dystonia DBS procedures.

Objective : Various skull base reconstruction techniques have been proposed for the endoscopic trans-sphenoidal approach (eTSA). These methods often involve multilayer closure using autologous fat grafts and fascia lata, frequently combined with lumbar drainage (LD). This study suggests a modification of graded reconstruction methods for low-grade (grade 0-2) cerebrospinal fluid (CSF) leaks, particularly grade 2 leaks, following eTSA for pituitary neuroendocrine tumor (PitNET). Methods : A total of 401 consecutive patients who underwent eTSA for PitNET between 2017 and 2022 at a single institution were retrospectively reviewed, and ultimately 338 patients with intraoperative low-grade CSF leaks were included. Skull base reconstruction was performed according to intraoperative CSF leak grades. Grade 2 leaks were further subcategorized into 2a and 2b based on the size of the diaphragmatic defect. Grades 0, 1, and 2a leaks were reconstructed using fibrin sealant patches, hydrogel sealant, and reinforcement with nasoseptal flap where required. Grade 2b cases underwent rigid reconstruction with hydroxyapatite. Autologous fat grafts, fascia lata, and perioperative LD were not used. Postoperative CSF leaks and other complications were analyzed. Results : Among the 338 cases, there were 235 grade 0, 55 grade 1, 40 grade 2a and eight grade 2b intraoperative CSF leaks. No postoperative CSF leaks occurred. Two cases of postoperative meningitis were observed in grade 2a, all of whom were treated successfully with antibiotics. Conclusion : Our graded reconstruction approach is an effective and efficient method to prevent CSF leaks after eTSA in PitNET patients with low-grade intraoperative CSF leaks. Further subdividing grade 2 leaks based on defect size enables more precise and reliable skull base reconstruction. Moreover, autologous fat grafts, fascia lata, and perioperative LD appear unnecessary in low-grade cases.

Objective : Anesthetics influence sympathetic tone, a key determinant of anesthetic depth. This study aimed to evaluate whether the perfusion index (Pi), reflecting propofol-mediated sympathetic modulation, can serve as a continuous real-time indicator of anesthetic depth during propofol-based total intravenous anesthesia (TIVA) requiring intraoperative neuromonitoring (IOM) in neurosurgery. Methods : This single center, prospective observational study included patients scheduled for anterior cervical decompression and fusion under propofol-based TIVA with IOM. Patients were eligible for inclusion (anterior cervical decompression and fusion) if they were aged 40-75 years and classified as American Society of Anesthesiologists physical status 1 or 2. At designated time intervals, from preinduction to extubation, the Bispectral index (BIS), a marker of anesthetic depth, alongside finger and ear perfusion indices (FPi and EPi) was assessed to examine correlations between these variables. The primary outcome was to find correlation between FPi and BIS. Results : Thirty participants were enrolled in this study. FPi and BIS showed significant correlation (correlation coefficient, -0.629; 95% confidence interval, -0.696 to -0.551; p<0.001), while EPi showed no significant correlation with BIS (correlation coefficient, 0.078; 95% confidence interval, -0.042 to 0.196; p=0.202). Conclusion : FPi monitoring may serve as a complementary technique for evaluating anesthetic depth during propofol-based TIVA requiring IOM in neurosurgery, as indicated by its correlation with BIS.

Dysembryoplastic neuroepithelial tumor (DNET) is a benign, pediatric brain tumor characterized by focal seizures, often progressing to drug-resistant epilepsy. Satellite lesions (SLs), small lesions adjacent to the main tumor mass typically embedded within normal parenchyma, are identified in approximately 50% of DNET cases and may contribute to recurrent seizures if not totally removed. However, detailed histopathological descriptions of SL remain limited to date. We report on an 8-year-old boy with medically intractable seizures and a T2 hyperintense mass in the left frontal lobe with smaller deep-seated SLs. The lesions were near totally removed, with deep-seated SLs successfully removed by performing a wider resection including the adjacent normal white matter with the aid of intraoperative ultrasonography, rather than through direct visual inspection. Histological analysis of deep-seated SLs showed homogeneous, typical DNET features identical to the main mass, including glioneuronal columns with oligodendrocyte-like cells and floating neurons within a mucoid matrix, confirming that deep-seated SLs are true tumors. In order to reduce the risk of recurrence, maximal safe resection of deep-seated SLs with the aid of ultrasonography might be helpful.

The Korean Brain Tumor Society (KBTS) was established in 1991 as the Korean Brain Tumor Study Group and has since evolved into a leading multidisciplinary academic organization in neuro-oncology. In its early phase, the society focused on building essential academic infrastructure, including the initiation of a nationwide brain tumor registry in 1992 and the implementation of structured educational programs. In 1999, this organization was renamed the Korean Brain Tumor Society, reflecting its expanding academic scope. In 2002, the KBTS launched the Journal of Korean Brain Tumor Society, establishing an official platform for scholarly communication. During the 2000s, the society expanded its academic and international engagement through scientific meetings-including the 2nd Meeting of the Asian Society for Neuro-Oncology (ASNO) in 2003 and the 7th ASNO Meeting in 2010-regional collaborations, and its admission to the Korean Academy of Medical Sciences in 2007. A major transition occurred in 2011 when its official journal, which was subsequently relaunched in 2013 as Brain Tumor Research and Treatment (BTRT), was integrated with the Journal of Korean Society for Neuro-Oncology, marking a strategic step toward internationalization. In 2018, the publication of the comprehensive textbook "Brain Tumors" further strengthened the society's academic foundation. In 2020, despite the challenges posed by the coronavirus disease 2019 pandemic, the KBTS maintained continuity through adaptive academic activities and the development of clinical recommendations. In 2022, the society successfully hosted the World Federation of Neuro-Oncology Societies in Seoul, underscoring its growing global leadership. This trajectory culminated in 2025, with the indexing of BTRT in Scopus, representing a significant milestone in international academic recognition. Over the past 35 years, the KBTS has made substantial contributions to research, education, and international collaboration while advancing clinical practice and surgical management through multicenter studies and the dissemination of operative strategies.