In Neurosurgery, stereotactic biopsy represents the main minimally invasive surgical technique to target deep and hard-to-reach brain sites that are not accessible by traditional surgical methods. The best trajectory for biopsy needle insertion is planned on the basis of CT or MRI studies. According to the relevant literature, although biopsy of the posterior cranial fossa with Leksell® Vantage™ Head Frame is possible, it involves several technical and clinical challenges. We describe an alternative configuration of the Leksell® Vantage™ system that addresses these limitations in the management of posterior cranial fossa lesions. At our Department (IRCCS Ospedale Policlinico San Martino in Genoa) we have used Leksell® Vantage™ stereotactic system together with Medtronic StealthStation™ S8 planning software to perform a series of seven stereotactic biopsies in the occipital or cerebellar region by rotating the stereotactic helmet 180° on the axial plane, resulting in an inversion of both the anteroposterior and lateral-lateral axes. We demonstrate that stereotactic posterior fossa biopsies can be performed with helmet rotation, without additional procedural complications. No similar approach has previously been described in the literature. This approach significantly enhances access to the posterior cranial fossa and occipital lesions. This optimisation improves manoeuvrability, provides a more advantageous viewing angle for the needle-biopsy trajectory and allows for a less complex preoperative planning. The approach remains minimally invasive and is generally compatible with execution under conscious sedation.

Meningeal melanocytoma of the central nervous system is a rare primary melanocytic neoplasm arising from the leptomeninges' melanocytes. It chiefly occurs in the posterior cranial fossa and rarely involves the spinal cord. The literature is bereft of lumbar spinal involvement by meningeal melanocytomas. Herein, we present a 17-year-old male patient who was incidentally diagnosed with a lumbar spinal meningeal melanocytoma during an imaging workup for backache following a fall. It was an extramedullary intradural tumor and was amenable to complete surgical removal in the spinal region. This case report highlights the importance of keeping the possibility of meningeal melanocytoma as a differential diagnosis of circumscribed intradural extramedullary neoplasms.

Intracranial meningiomas, though typically slow-growing and benign, can present significant diagnostic challenges when located in atypical anatomical sites or associated with unusual clinical manifestations. This case series highlights five patients with meningiomas arising in uncommon regions, including the olfactory groove, intraventricular space, sinonasal cavity, and anterior and posterior cranial fossae. Clinical presentations ranged from anosmia and visual disturbances to cranial nerve deficits and features of raised intracranial pressure. Advanced imaging, particularly MR spectroscopy, was instrumental in diagnosis, demonstrating characteristic choline and alanine peaks that differentiated meningiomas from other neoplasms. Some lesions displayed heterogeneous enhancement, irregular margins, and bone erosion, mimicking aggressive or non-meningothelial tumours. Recognition of these atypical radiological and clinical variants is crucial for accurate diagnosis, optimal surgical planning, and improved patient outcomes.

The cranium is a highly integrated structure composed of partially independent yet interrelated modules with different origin and developmental pathways. Throughout growth, these modules interact extensively in response to various intrinsic and extrinsic factors, ultimately forming a cohesive and functionally unified structure. Consequently, morphological changes in one cranial unit are expected to influence the development and shape of others. Considering the known vault alterations associated with metopism, we assume that the cranial base is also modified in metopic skulls. To test this hypothesis, we compared shape and size of the internal cranial base in metopic (46) and control (183) dry crania of contemporary adult Bulgarian males using geometric morphometric techniques. The crania were scanned using an industrial µCT system. Three-dimensional coordinates of 37 (9 midsagittal and 14 bilateral) landmarks were recorded on the endocranial surface. The landmarks were grouped into four configurations outlining the internal cranial base and its compartments: anterior cranial fossa, middle cranial fossa, and posterior cranial fossa. No significant size differences were observed between the metopic and control series. Shape comparisons revealed significant differences in all configurations except the posterior cranial fossa. However, Principal Component Analysis did not demonstrate clear separation between the groups, indicating that the observed shape variation cannot be attributed solely to the persistence of the metopic suture.

Congenital cystic malformations of the posterior cranial fossa encompass Dandy-Walker malformation, Blake's pouch cyst, and arachnoid cyst, which are usually associated with increased cerebrospinal fluid in the posterior fossa. Although isolated cerebellar vermis hypoplasia courses with a normal posterior fossa volume and is not associated with a cyst, the smaller volume of the cerebellar vermis results in a relative increase in cerebrospinal fluid compared to the posterior fossa volume and is considered a differential diagnosis. Furthermore, mega cisterna magna, which is an anatomical variant, is also a differential diagnosis of these congenital malformations. Usually, these malformations are diagnosed through screening prenatal ultrasound. However, fetal magnetic resonance imaging (MRI) can confirm, change, or complement questionable findings and identify associated malformations. Therefore, fetal MRI plays an essential role in evaluating fetuses with suspected brain malformations. Manual MRI segmentation can facilitate the understanding of these congenital cystic posterior fossa malformations. Three-dimensional (3D) segmentation offers a spatial view of the abnormalities, as well as their relationships with adjacent anatomical structures, allowing a better multidisciplinary team approach. The aim of this article is to review the embryology of the posterior cranial fossa, discuss the fetal MRI protocol to evaluate the cystic posterior fossa malformations, and to illustrate the key MRI features of these malformations.

Background/Objectives: The cranial base, especially the posterior cranial fossa, has openings with population-specific morphometry. This study aimed to assess the morphometric characteristics of the major posterior cranial fossa openings (foramen magnum, jugular foramen, internal acoustic opening) in the Turkish population and evaluate their utility for sex estimation. It also aimed to provide population-specific reference values for forensic anthropology and cranial base surgery. Methods: This prospective study included 304 adult skulls (151 female, 153 male) obtained from forensic autopsy cases, all of which had preserved anatomical integrity. Structures in the posterior cranial fossa were exposed following a standardized dissection protocol. A total of 18 morphometric parameters were measured using a digital caliper. Inter-sex comparisons were performed, and the diagnostic performance of the parameters for sex differentiation was evaluated using receiver operating characteristic (ROC) curve analysis. Results: All morphometric parameters and inter-foraminal distances were significantly larger in male individuals compared to females (p < 0.001). Similarly, ellipticity indices were higher in males than in females (all p < 0.001). ROC analysis revealed that right internal acoustic opening transverse diameter (RIAO-T), left and right jugular foramen transverse diameters (RJF-T and LJF-T) parameters possess exceptionally high discriminatory power, yielding accuracies greater than 99%. Conclusions: Components of the posterior cranial fossa exhibit marked sexual dimorphism in the Turkish population. These morphometric data provide valuable anatomical references for forensic identification, aid in preserving neurovascular structures, and support safe surgical planning in cranial base procedures.

Secondary malignant neoplasms are a rare but feared late complication of pediatric cancers. Radiation therapy is a well-established risk factor for the development of thyroid tumors, particularly in children, whose thyroid gland is sensitive to the carcinogenic effects of ionizing radiation.This is the case of a 16-year-old female patient who was diagnosed at the age of 5 with a medulloblastoma of the posterior cranial fossa, which was surgically treated and irradiated. Ten years later, a cervical mass developed, leading to the diagnosis of papillary thyroid carcinoma (PTC) with lymph node involvement. Pulmonary nodules/micronodules were identified,consistent with hematogenous dissemination. The patient received two doses of radioactive iodine therapy, in the context of an elevated postoperative thyroglobulin level. Follow-up chest CT revealed progression of a suspicious right lower lobe pulmonary micronodule, while whole-body scintigraphy showed multiple iodine-avid foci.This case highlights the need for long-term surveillance in pediatric cancer survivors due to the elevated risk of radiationinduced secondary thyroid malignancies.

Arachnoid cysts are predominantly congenital pathologies associated with cleft of arachnoid membrane of spinal cord or brain. Arachnoid cysts present with cerebral, hypertensive-hydrocephalic and focal symptoms. Localization of intracranial arachnoid cysts can vary. Only 12% of symptomatic arachnoid cysts are localized in posterior cranial fossa. To present successful treatment of a patient with retrosellar arachnoid cyst, review available literature data and compare clinical course and treatment outcomes. A 29-year-old female patient presented with long-term history of headache, dizziness, diplopia and statodynamic disturbances. Magnetic resonance imaging revealed giant retrosellar arachnoid cyst compressing the brainstem and causing hydrocephalus. The PubMed database was screened (2015-2025). Only full-text articles In Russian and English were included. References of these articles comprised secondary searching. Endoscopic cystoventriculocisternostomy of arachnoid cyst in posterior fossa was performed. Postoperative period was uneventful. Neurological and ophthalmological status was the same. MRI revealed significant improvement including cyst shrinkage and regression of symptoms over a 3-month period. There were only 7 relevant reports. Correct surgical approach is confirmed by cyst shrinkage after surgery and clinical follow-up data.

BackgroundPediatric central nervous system (CNS) tumors are the second most common malignancy in children and are associated with significant long-term morbidity despite advancements in therapy. Endocrine dysfunction is one of the most frequent and impactful late sequelae, requiring timely detection and management. This study aimed to investigate the timing and risk factors associated with endocrine dysfunction in pediatric brain tumor survivors and to propose optimized follow-up protocols.MethodsA cohort of 33 pediatric patients with brain tumors, excluding craniopharyngiomas, pituitary adenomas, and germ cell tumors, treated at the Pediatric Oncology Unit of Fondazione Policlinico Universitario “Agostino Gemelli” IRCCS in Rome (2005–2015), was retrospectively analyzed. Endocrine dysfunction was assessed through clinical and laboratory evaluations, with a median follow-up of 114.1 months.ResultsEndocrine dysfunction was identified in a high percentage of patients, with hypothyroidism and panhypopituitarism being the most common. Age at diagnosis and treatment influenced the appearance and the timing of dysfunction. Hypothalamic and suprasellar tumors were associated with early onset, while tumors in posterior cranial fossa exhibited delayed onset.ConclusionsTumor location and patient age are critical determinants of the timing of endocrine dysfunction in pediatric brain tumor survivors. We propose a stratified follow-up based on tumor location, with immediate evaluation for hypothalamic and supratentorial tumors and periodic assessments for other regions. These tailored recommendations aim to ensure timely detection and management of endocrine complications, improving outcomes and quality of life. Future research with larger cohorts is needed to validate and refine these findings.

Infratentorial brain metastases (BMs) are life-threatening because of the unique anatomical features and physiological functions of the posterior cranial fossa. However, the comparative prognosis of infratentorial BM and supratentorial BM remains poorly understood. We conducted a matching comparison of the prognosis between non-small cell lung cancer (NSCLC) patients with and without infratentorial BM and analyzed prognostic factors, including the radiotherapy (RT) method. 392 NSCLC patients who underwent brain RT from July 2010 until June 2023 were analyzed. After 1:1 propensity matching, we compared 115 patients with only supratentorial BMs (supraT-alone group) and 115 patients with infratentorial ± supratentorial BMs (infraT ± supraT group). We assessed intracranial control and overall survival (OS) using Kaplan-Meier and Cox regression. There was no statistical difference for extracranial progression-free survival (PFS), intracranial local PFS, or distant PFS. The supraT-alone group had significantly better OS (median: 35.3 vs. 24.2 months, p=0.021). The supraT-alone group in the multivariate analysis had BM resection (p=0.031), targeted therapy (p<0.001), and immune therapy (p=0.006) associated with improved OS. The infraT ± supraT group had RT method (p=0.002), ≤60 years of age (p=0.002), targeted therapy (p=0.017), and number of extracranial metastases (p<0.001) when reporting OS. We confirmed that WBRT+boost and SRT improved OS compared to WBRT alone. There was no statistical difference in OS for WBRT+boost and SRT. The overall grade 3-4 acute toxicities were similar for both groups. Our study suggests that infratentorial BMs in NSCLC lead to worse OS. However, local high-dose RT strategies (SRT or WBRT+boost) may confer survival benefits to patients who present with infratentorial involvement.

The MRI imaging traits of pediatric posterior cranial fossa neoplasms overlap highly, leading to difficulties in preoperative diagnosis. Their treatment strategies differ significantly, and traditional deep learning models have limitations in multi - sequence MRI fusion and clinical interpretability, so new solutions are urgently needed. This study aims to develop a 2.5D multi - sequence MRI deep learning framework (ResSwinT) that integrates Residual Network and Swin Transformer, to achieve automatic classification of three main Pediatric posterior fossa tumors-Pilocytic astrocytoma (PA), Medulloblastoma (MB), and Ependymoma (EP), and enhance the interpretability of the model through the SHAP method, so as to provide a more reliable auxiliary decision-making basis for clinical practice. This study retrospectively collected 309 pediatric patients confirmed by pathology, including 109 PA, 130 MB and 70 EP. The MRI data of these patients included five sequences: T1WI, T1C, T2WI,FLAIR, and ADC. After preprocessing steps such as N4 bias field correction, resampling, sequence registration, and intensity normalization, samples were constructed using a 2.5D image construction strategy, and the ResSwinT model is designed. Its performance was compared with seven deep learning models such as Residual Network 18 and VGG16, and SHAP analysis was used to analyze trait contributions. The proposed ResSwinT model outperforms existing commonly used deep learning models in all classification tasks, particularly showing outstanding performance in terms of area under the curve(AUC) and overall accuracy(ACC). For the PA vs Non-PA task: ACC 89.5%, AUC 0.975; for the MB vs Non-MB task: ACC 93.7%, AUC 0.978; for the EP vs Non-EP task: Acc 87.5%, AUC 0.937. SHapley Additive exPlanations(SHAP) analysis shows that the model pays high attention to the gross tumor volume and its surrounding structures, and its decision-making basis is highly consistent with key imaging biomarkers, verifying the interpretability and clinical relevance of the model. ResSwinT achieves high-precision classification of pediatric posterior fossa tumor through 2.5D multi-sequence fusion and cross-attention mechanism. SHAP attribution analysis reveals the biological basis of the model's decision-making, providing clinicians with an interpretable AI-assisted diagnostic tool, and is expected to optimize individualized treatment strategies.

The present study aimed to describe the clinical features and survival of patients with temporal bone malignant tumors. A total of 20 consecutive cases treated at Beijing Tiantan Hospital (Beijing, China) between March 2014 and March 2022 were retrospectively reviewed. Of the 20 patients, 16 were men and 4 were women, with an age range of 9-90 years old. The pathological types included squamous cell carcinoma (SCC; n=7), adenoid cystic carcinoma (ACC; n=7), chondrosarcoma (n=2), fibrosarcoma (n=1), endolymphatic cystic papillary adenocarcinoma (n=1), rhabdomyosarcoma (n=1) and low-grade malignant peripheral nerve sheath tumor (n=1). Patients initially diagnosed with SCC and ACC were staged according to the revised Pittsburgh classification system (T1, n=1; T3, n=5; T4, n=8). All patients received surgery, followed by postoperative radiotherapy (RT) with/without chemotherapy in 10 patients. Kaplan-Meier analysis was used to calculate the survival rate, and the log-rank test was applied to compare the differences in survival. The duration of follow-up ranged from 1 to 140 months. Notably, the 3- and 5-year disease-specific survival (DSS) rates were 79 and 73%, and the 3- and 5-year overall survival (OS) rates were 74 and 68%. Pathological type and posterior cranial fossa meningeal involvement were significantly associated with both OS and DSS. Furthermore, patients with a positive surgical margin had a significantly worse DSS rate. In conclusion, the incidence of temporal bone malignancies is low with an insidious onset. Radical resection is the main treatment option, and postoperative RT with/without chemotherapy may be supplemented in cases of an advanced stage or when tumors have a positive surgical margin.

Introduction: Prone positioning is essential for various surgical procedures, including spinal surgeries, posterior cranial fossa procedures and urological interventions, as it provides optimal access to posterior anatomical structures. However, this positioning significantly alters respiratory mechanics and cardiovascular physiology, potentially affecting patient safety during general anaesthesia. Peak Airway Pressure (PAP) and Endotracheal Tube (ETT) cuff pressure are critical parameters that require careful monitoring during prone positioning to prevent complications such as barotrauma and tracheal injury. Aim: To evaluate simultaneous changes in PAP and ETT cuff pressure during prone positioning under general anaesthesia and to assess associated haemodynamic alterations. Materials and Methods: This prospective observational study was conducted at Department of Anaesthesiology and Critical Care, Adesh Institute of Medical Sciences and Research, Adesh University, Bathinda, Punjab, India. The study enrolled 105 consecutive American Society of Anaesthesiologists (ASA) I-II patients scheduled for elective procedures requiring prone positioning. Standardised protocols were used to document PAP, ETT cuff pressure and haemodynamic variables at multiple time points: baseline in the supine position, immediately after prone positioning and at 15-minute intervals throughout the procedure. Statistical analysis employed paired comparisons, with a significance threshold of p-value &lt;0.05. Results: A total of 105 patients completed the study (mean age 45.36±10.26 years; 62.9% female; mean Body Mass Index (BMI) 21.41±2.56 kg/m²). Transitioning from supine to prone position produced significant respiratory mechanical alterations. Baseline supine PAP (19.03±3.35 cm H2 O) progressively increased to a maximum of 34.36±2.59 cm H2 O during prone maintenance (p-value &lt;0.001), representing an 80.6% elevation. Similarly, ETT cuff pressure increased from baseline (24.64±2.99 cm H2 O) to 43.65±4.49 cm H2 O at maximum prone measurement (p-value &lt;0.001). Cardiovascular parameters demonstrated significant alterations during the initial 15 minutes post-positioning before stabilising during the maintenance phase. Conclusion: In patients under general anaesthesia, the prone position significantly increases PAP and ETT cuff pressure. This finding underscores the importance of regular monitoring and timely interventions to limit the risks associated with elevated pressures.

Posterior fossa epidural hematoma (PFEDH) is a rare condition, accounting for only 0.1-0.3% of all traumatic brain injuries. Patients can rapidly deteriorate due to brainstem compression caused by bleeding in the posterior cranial fossa. Timely surgical intervention is critical, but currently, there is no consensus on the surgical indication and technical approach for pediatric PFEDH. Case Presentation: A five-year-old boy presented with occipital trauma, headache, vomiting, and altered consciousness after a fall from a 1-meter height. Primary survey was clear with a Glasgow Coma Scale (GCS) score of E3M6V4 and slow pupillary reflexes while secondary examination revealed a 1x2 cm cephalhematoma over the right posterior fossa region. Head CT scan revealed a posterior fossa liquid epidural hematoma measuring 5.4 x 2.2 x 4cm with cerebellar displacement. The patient underwent a mini-craniectomy and recovered with a relatively short operative duration, minimal blood loss, and a short hospital stay without neurological deficits. Mini-craniectomy emerges as a viable and promising alternative procedure in the management of carefully selected pediatric PFEDH cases, particularly those that are liquid or of moderate volume, allowing for efficient evacuation with minimal surgical morbidity with a good prognostic outcome

The median suboccipital approach (MSOA) provides access to the posterior cranial fossa (PCF) and craniovertebral junction (CVJ). This study outlines a step-by-step description of the "chevron-shaped" dural opening technique for MSOA, emphasizing its anatomical rationale and presenting surgical outcomes.Between January 2020 and December 2024, 76 patients underwent MSOA at the Neurosurgical Department of the ASST Cremona, Italy. Exclusion criteria included a history of previous PCF/CVJ surgery or preoperative imaging evidence of oblique occipital sinus (OS). The chevron-shaped durotomy involved two oblique lateral incisions directed lateromedially and craniocaudally, converging at the midline over the foramen magnum, enabling the OS and marginal sinus to be severed safely. Intraoperative and postoperative complications were systematically recorded.The OS was identified intraoperatively in 93.4% of patients. Significant intraoperative venous bleeding occurred in three patients (3.9%) and was successfully controlled in all instances. No intraoperative blood transfusions were required, although five patients (6.6%) required postoperative transfusions. Intracranial hemorrhage occurred in two patients (2.6%). Asymptomatic pseudomeningocele was observed in 25 cases (32.9%) on CT scan at postoperative day 7, persisting in seven (9.2%) on CT at day 30. One patient (1.3%) developed bacterial meningitis associated with CSF leakage, which resolved with antibiotics and lumbar drainage. Hydrocephalus developed in three patients (3.9%), necessitating ventriculo-peritoneal shunt placement; no correlation with underlying pathology was noted.The dural opening for MSOA requires detailed anatomical knowledge, accurate preoperative imaging, and individualized surgical planning owing to significant inter-individual anatomical variability. The chevron-shaped dural opening technique represents a safe, effective and anatomically grounded alternative to traditional PCF durotomies, except in patients with an oblique OS.

Objective: To improve the understanding of the clinical manifestation of immunoglobulin G4-related disease (IgG4-RD) with neurological involvement. Methods: Patients presenting with neurological symptoms and biopsy-confirmed IgG4-RD were enrolled between March 2014 and March 2024 from the Department of Neurology of Xuanwu Hospital of Capital Medical University. Medical record data of all patients were retrospectively reviewed, including clinical manifestations, laboratory findings, radiological results, pathology, treatments, and outcomes. RD were enrolled between March Results: Nine patients (five males, four females; median age at onset: 63 years) were included in the study. Neurological manifestations consisted of pachymeningitis in six cases, peripheral nerve involvement in two, and brain parenchyma involvement in one. Four patients displayed isolated neurologic symptoms. The most common clinical manifestations were headache and cranial nerve palsy, each involving five cases. Magnetic resonance imaging showed thickening and enhancement of the dura mater in the six patients with pachymeningitis. Four of these cases involved the posterior cranial fossa, 3 presented with an inflammatory pseudotumor, and 2 involved the spinal cord. Four patients with pachymeningitis had normal serum IgG4 concentrations. Eight patients exhibited elevated serum C-reactive protein or erythrocyte sedimentation rates, with some also showing decreased complement C3 and C4 levels. Cerebrospinal fluid immunoglobulin was elevated in all nine cases. In all cases, histopathologic biopsy results showed extensive infiltration of lymphocytes and plasma cells, with the latter displaying IgG4+abnormalities. All patients received glucocorticoid therapy, with six also receiving immunosuppressants. All patients were followed up for a median of 30 months, with outcomes including two complete remissions, five partial remissions, one unchanged condition, and one death. Six patients experienced a relapse. Conclusions: Isolated hypertrophic pachymeningitis is the most common manifestation of IgG4-RD, often occurring in the absence of elevated serum IgG4 levels. Peripheral nerve and brain parenchyma involvement can also be seen. Clinical manifestations are non-specific, and histopathologic biopsy is frequently required for diagnosis. Although the disease responds well to hormone treatment, recurrence is common. Early combined immunosuppressive therapy can improve prognosis.

Occipital transtentorial approach for posterior cranial fossa lesions located away from the midsagittal plane: A technical note

Biallelic mutations in XPNPEP3 gene, encoding a mitochondrial peptidase, mainly cause nephronophthisis, but associated muscle involvement remains poorly described. We report here a 44-year-old male presenting since childhood with exercise intolerance and recurrent rhabdomyolysis. Electroneuromyography revealed a sensory axonal neuropathy and brain MRI showed white matter lesions in the posterior cranial fossa. Muscle biopsy revealed ragged-red fibers, COX negative fibers and abnormal mitochondria in electron microscopy. Whole genome sequencing identified a homozygous frameshift variant in the XPNPEP3 gene. Our results expand the spectrum associated with XPNPEP3 variants, including metabolic myopathy with subclinical central and peripheral nervous system involvement.

BACKGROUND: During the Great Patriotic War, craniocerebral combat wounds were classified. Currently, gunshot wounds demonstrate a greater variety, severity, and extent of tissue injury in craniocerebral regions on the periphery of the wound canal compared to wounds from past wars. Furthermore, advanced diagnostic techniques that can identify previously undescribed cerebral wound canals, which were generally considered fatal, are now available. Thus, new classification systems for craniocerebral gunshot wounds are required. AIM: The work aimed to broaden the fundamental classification of craniocerebral gunshot wounds by including the current clinical and anatomical findings, facilitating a more comprehensive clinical diagnosis. METHODS: The assessment findings and treatment outcomes of two groups of wounded patients were analyzed. Group 1 included 127 patients with craniocerebral gunshot wounds who had been treated in a military hospital during the Soviet–Afghan War. Group 2 comprised 67 wounded participants of modern armed conflicts who were treated at the Neurosurgery Clinic of the Kirov Military Medical Academy. RESULTS: A contemporary clinical and anatomical classification of craniocerebral gunshot wounds was developed. This classification includes posterior cranial fossa (the cerebellum and brainstem) wounds. The proposed classification offers a framework for more accurate triaging based on injury severity. This facilitates decision-making for surgical prioritization, including in scenarios involving mass admissions. Primary attention should be given to patients with wound canal passing through the cortex and white matter of the brain. Generally, the more convex trajectory of the wound canal is associated with less severe brain injury. Surgical procedures are performed after stabilization of vital signs in patients with wound canals passing through the first-level (e.g., subcortical structures, ventricles, and brainstem) and second-level (e.g., cortex and cerebellar hemispheres) brain structures. The prognosis of these wounded patients largely depends on the severity and extent of damage to vital brain structures. CONCLUSION: The developed clinical and anatomical classification is beneficial for elucidating the nature of craniocerebral gunshot wounds, facilitating a targeted triage of admitted wounded patients, ensuring surgical prioritization, and predicting the prognosis and outcome of craniocerebral wounds.

The uniqueness of human brain growth and development has been considered promising for its contribution to understanding the origins of the unique human cognitive abilities. Compared with that of chimpanzees, the human endocranium undergoes several characteristic shape changes immediately after birth, which has been termed "endocranial globularization." However, how the brain structures and surrounding neurocranium interact with each other during early development in the context of brain-neurocranium integration remains to be investigated. We investigated shape and size changes in the human brain and endocranium during postnatal development using magnetic resonance imaging,and analyzed spatial constraints and interactions among subdivisions of the brain influencing endocranial morphology. Our results suggest that, during postnatal development, the relative size changes of supratentorial and infratentorial regions and the cranial base largely constrain brain and endocranial shape. Specifically, a disproportionate increase in the size of the infratentorial region (i.e., cerebellum plus brainstem) relative to the cranial base affects the infratentorial spatial packing constraint in neonates, causing inferoposterior expansion of the posterior cranial fossa and coronal reorientation of the petrous pyramid of the temporal bone without flattening the angle between the two sides of the tentorium cerebelli. The dramatic size increase of the infratentorial region relative to the cranial base immediately after birth is inferred to be characteristic of human development and should be compared with non-human primates and potentially applied to fossil cranial series to obtain more evolutionary insight into the human cognitive ability.