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BACKGROUND: The process of bone healing is complex and involves the participation of osteogenic stem cells, extracellular matrix, and angiogenesis. The advancement of bone regeneration materials provides a promising opportunity to tackle bone defects. This study introduces a composite hydrogel that can be injected and cured using UV light. RESULTS: Hydrogels comprise bioactive glass (BG) and PCL@GelMA coaxial nanofibers. The addition of BG and PCL@GelMA coaxial nanofibers improves the hydrogels mechanical capabilities (353.22 ± 36.13 kPa) and stability while decreasing its swelling (258.78 ± 17.56%) and hydration (72.07 ± 1.44%) characteristics. This hydrogel composite demonstrates exceptional biocompatibility and angiogenesis, enhances osteogenic development in bone marrow mesenchymal stem cells (BMSCs), and dramatically increases the expression of critical osteogenic markers such as ALP, RUNX2, and OPN. The composite hydrogel significantly improves bone regeneration (25.08 ± 1.08%) in non-healing calvaria defects and promotes the increased expression of both osteogenic marker (OPN) and angiogenic marker (CD31) in vivo. The expression of OPN and CD31 in the composite hydrogel was up to 5 and 1.87 times higher than that of the control group at 12 weeks. CONCLUSION: We successfully prepared a novel injectable composite hydrogel, and the design of the composite hydrogels shows significant potential for enhancing biocompatibility, angiogenesis, and improving osteogenic and angiogenic marker expression, and has a beneficial effect on producing an optimal microenvironment that promotes bone repair.

Human embryonic bone and joint formation is determined by coordinated differentiation of progenitors in the nascent skeleton. The cell states, epigenetic processes and key regulatory factors that underlie lineage commitment of these cells remain elusive. Here we applied paired transcriptional and epigenetic profiling of approximately 336,000 nucleus droplets and spatial transcriptomics to establish a multi-omic atlas of human embryonic joint and cranium development between 5 and 11 weeks after conception. Using combined modelling of transcriptional and epigenetic data, we characterized regionally distinct limb and cranial osteoprogenitor trajectories across the embryonic skeleton and further described regulatory networks that govern intramembranous and endochondral ossification. Spatial localization of cell clusters in our in situ sequencing data using a new tool, ISS-Patcher, revealed mechanisms of progenitor zonation during bone and joint formation. Through trajectory analysis, we predicted potential non-canonical cellular origins for human chondrocytes from Schwann cells. We also introduce SNP2Cell, a tool to link cell-type-specific regulatory networks to polygenic traits such as osteoarthritis. Using osteolineage trajectories characterized here, we simulated in silico perturbations of genes that cause monogenic craniosynostosis and implicate potential cell states and disease mechanisms. This work forms a detailed and dynamic regulatory atlas of bone and cartilage maturation and advances our fundamental understanding of cell-fate determination in human skeletal development.

Cranial sutures separate neighboring skull bones and are sites of bone growth. A key question is how osteogenic activity is controlled to promote bone growth while preventing aberrant bone fusions during skull expansion. Using single-cell transcriptomics, lineage tracing, and mutant analysis in zebrafish, we uncover key developmental transitions regulating bone formation at sutures during skull expansion. In particular, we identify a subpopulation of mesenchyme cells in the mid-suture region that upregulate a suite of genes including BMP antagonists (e.g. grem1a) and pro-angiogenic factors. Lineage tracing with grem1a:nlsEOS reveals that this mid-suture subpopulation is largely non-osteogenic. Moreover, combinatorial mutation of BMP antagonists enriched in this mid-suture subpopulation results in increased BMP signaling in the suture, misregulated bone formation, and abnormal suture morphology. These data reveal establishment of a non-osteogenic mesenchyme population in the mid-suture region that restricts bone formation through local BMP antagonism, thus ensuring proper suture morphology.

Objective: This study aimed to evaluate the effectiveness of biomaterials in bone healing of critical bone defects created by piezoelectric surgery in rat calvaria. Method and materials: Histomorphologic analysis was performed to assess bone regeneration and tissue response. Fifty animals were randomized into five groups with one of the following treatments: Control group (n = 10), spontaneous blood clot formation with no bone fill; BO group (Bio-Oss, Geistlich Pharma; n = 10), defects were filled with bovine medullary bone substitute; BF group (Bonefill, Bionnovation; n = 10), defects were filled with bovine cortical bone substitute; hydroxyapatite group (n = 10), defects were filled with hydroxyapatite; calcium sulfate group (n = 10), defects were filled with calcium sulfate. Five animals from each group were euthanized at 30 and 45 days. The histomorphometry calculated the percentage of the new bone formation in the bone defect. Results: All data obtained were evaluated statistically considering P < .05 as statistically significant. The results demonstrated the potential of all biomaterials for enhancing bone regeneration. The findings showed no statistical differences between all the biomaterials at 30 and 45 days including the control group without bone grafting. Conclusion: In conclusion, the tested biomaterials presented an estimated capacity of osteoconduction, statistically nonsignificant between them. In addition, the selection of biomaterial should consider the specific clinical aspect, resorption rates, size of the particle, and desired bone healing responses. It is important to emphasize that in some cases, using no bone filler might provide comparable results with reduced cost and possible complications questioning the very frequent use of ridge presentation procedures. [ABSTRACT FROM AUTHOR]

Ornithopod dinosaurs appeared during the Middle Jurassic, but it was in the Lower Cretaceous they started their successful evolutionary history. Different phylogenies describing the evolutionary relationships of Ornithopoda are mostly based on cranial features, however there is a lack of well-preserved and complete skulls for the basal member of the clade, hampering our knowledge on the mode and tempo of these herbivorous dinosaurs. Here we describe YLSNHM 01942, a well-preserved skull of a juvenile neornithischian from the Liaoning Province of China. The specimen was scanned with a μCT scan, and all the elements were segmented and extrapolated for description. The specimen shows a ventral deformation due to the compression of the sediment, and a few rostral elements were artificially added. The specimen is attributed to the basal ornithopod Jeholosaurus shangyuanensis because of the presence of a large foramen in the quadratojugal, however it lacks the nodular ornamentation on the postorbital and jugal, herein interpreted as an ontogenetic feature. This, together with the disarticulation degree of the cranial elements, suggest YLSNHM 01942 represents a juvenile Jeholosaurus. The endosseous labyrinth is tentatively reconstructed, although the disarticulation of the neurocranial bones hampers its complete reconstruction. Thanks to the analysis of previously undescribed inner neurocranial bones (such as the prootics, the exoccipital/ophistotic, basioccipital, and basisphenoid), we improve the previous phylogenetical scoring for J. shangyuanensis, and perform a phylogenetical analysis adding the basal ornithopod Changmiania liaoningensis and the recently re-evaluated Ajkaceratops kozmai. The phylogenetical analysis reports a well-supported base of Ornithopoda, with C. liaoningensis as the most basal ornithopod, and a resolved topology for Nanosaurus agilis, Changchunsaurus parvus, Haya griva, Yandusaurus hongheensis and J. shangyuanensis. [ABSTRACT FROM AUTHOR]

The first partial skeleton of a carcharodontosaurid theropod was described from the Egyptian Bahariya Oasis by Ernst Stromer in 1931. Stromer referred the specimen to the species Megalosaurus saharicus, originally described on the basis of isolated teeth from slightly older rocks in Algeria, under the new genus name Carcharodontosaurus saharicus. Unfortunately, almost all of the material from the Bahariya Oasis, including the specimen of Carcharodontosaurus was destroyed during World War II. In 1996, a relatively complete carcharodontosaurid cranium was described from similar aged rocks in Morocco and designated the neotype of the species Carcharodontosaurus saharicus in 2007. However, due to the destruction of the original material, comparisons of the neotype to the Egyptian fossils have so far only been done cursorily. A detailed reexamination of the available information on the Egyptian carcharodontosaurid, including a previously undescribed photograph of the exhibited specimen, reveals that it differs from the Moroccan neotype in numerous characters, such as the development of the emargination of the antorbital fossa on the nasals, the presence of a horn-like rugosity on the nasal, the lack of a dorsoventral expansion of the lacrimal contact on the frontals, and the relative enlargement of the cerebrum. The referability of the Egyptian specimen to the Algerian M. saharicus is found to be questionable, and the neotype designation of the Moroccan material for C. saharicus is accepted here under consideration of ICZN Atricle 75, as it both compares more favorably to M. saharicus and originates from a locality closer to the type locality. A new genus and species, Tameryraptor markgrafi gen. et sp. nov, is proposed for the Egyptian taxon. The theropods of the Bahariya Oasis and the Moroccan Kem Kem Group are thus not as closely related as previously thought, and the proposed faunal similarities between these two strata need further examination. [ABSTRACT FROM AUTHOR]

Tiger and lion bones are valuable subjects of trafficking. They can be easily interchanged. The aim of this study was to develop a methodology to quickly distinguish between tiger and lion skulls. From a number of features reported in the literature, a set of seven significant characters was identified that can be recognized even in photographs. A methodology for their assessment was developed. Using a combination of them allows for a very reliable morphological distinction between the two species. A new character, the greater palatine foramen ratio, of both adult and juvenile skulls, has not been described in the context of identification of tiger and lion skulls before. [ABSTRACT FROM AUTHOR]

Skulls with high optical scattering and acoustic attenuation are a great challenge for photoacoustic imaging for human beings. To explore and improve photoacoustic generation and propagation, we conducted the photoacoustic simulation and image reconstruction of the multi-layer brain model with an embedded blood vessel under different optical source types. Based on the optical simulation results under different types of optical sources, we explored the characteristics of reconstructed images obtained from acoustic simulations with and without skull conditions. Specifically, we focused on the detection of blood vessels and evaluated the image reconstruction features, morphological characteristics, and intensity of variations in the target vessels using optical and acoustic simulations. The results showed that under the initial PA signals, the types of optical source types corresponding to the strongest and weakest photoacoustic signals at different positions within the target region were consistent, while the optical source types were different in the reconstructed images. This study revealed the characteristics of acoustic signal transmission with and without skull conditions and its impact on image reconstruction. It further provides a theoretical basis for the selection of optical sources. [ABSTRACT FROM AUTHOR]

In this study, a (TiB + TiC + Y2O3)/α-Ti composite was prepared by induction skull melting to investigate its creep behavior and microstructure evolution under different temperatures and stresses. The results show that the microstructure of the composite in the as-cast state is a basket-weave structure, and the main phase composition is α lamella, containing a small amount of β phase and equiaxed α phase. The creep life of the composite decreases significantly when the temperature is increased from 650 °C to 700 °C, and the steady-state creep rate is increased by 1 to 2 orders of magnitude. The creep stress exponent at 650 °C and 700 °C is 2.92 and 2.96, respectively, and the creep mechanism of the titanium matrix composite is dominated by dislocation movement. TiB and TiC exhibit synergistic strengthening effects, and Y2O3 remains stable during creep. The reinforcements strengthen the composite by impeding the dislocation movement. The accelerated dissolution of β phase is one of the major reasons for the decrease of creep properties of composite with increasing temperature and stress. Silicide precipitation was observed near the reinforcements and dissolved β-Ti, mainly in elliptical or short rod shapes, which pins dislocations and improves the creep performance of the composite. The results of this study can provide theoretical guidance and practical reference for the subsequent development and application of hybrid reinforced titanium matrix composites. [ABSTRACT FROM AUTHOR]

The genus Aprotodon is a special group of rhinoceroses, which has a very long survival time frame but a relatively limited distribution in Asia. Herein, we report on a well-preserved and complete skull found in the lower layers of the Zhang'enbao Formation from the Early Miocene age in Tongxin County, China. The morphology of the new specimen is different from all the known species of Aprotodon in its smaller size, with both sides of the parietal crest fused and forming a sagittal crest, the V-shaped anterior edge of the posterior nares positioned at the level of M2, the weak supraorbital tuberosity, the developed and multiple crista on premolars, and the reduced lingual cingulum, forming a pillar around the entrance of the medisinus on molars. Based on these, we refer the Tongxin specimen to a new species, A. qiui sp. nov. Phylogenetic analysis reveals that A. qiui sp. nov. and other members of Aprotodon are in a stable monophyletic clade. A. qiui sp. nov. is the sister taxon to A. lanzhouensis. [ABSTRACT FROM AUTHOR]

Traditional Dipodomys (sub)species identification uses geography, phenotype, and external/skull measurements. Such measurements are correlated with size and thus redundant. I assessed the value of scaled cranial shape, based on two‐dimensional landmarks (analyzed using geometric morphometric methods) in distinguishing Dipodomys taxa, and in summarizing their variation. My dataset includes 601 adult specimens from 20 species (49 operational taxonomic units ‐ OTUs) across 190 localities. Cranial shape was highly useful in classifying Dipodomys taxa without considering geography. The auditory bulla was the most variable region—taxa differed in its hypertrophy, accompanied by different degrees of nearby structure crowding. Cranial shape was weakly allometric, with no significant sexual dimorphism. Weak size dimorphism was detected. (Sub)specific taxonomy is not reflective of shape variation, as the number of subspecies per species is not associated with disparity. Shape had significant phylogenetic signal, but subspecies did not always cluster with conspecifics and species did not always cluster according to phylogenetic relationship/taxonomy. Shape variation was correlated with climate, and species differed in morphological disparity and degree of specialization, which may contribute to divergence in shape variation patterns from phylogeny. D. deserti was the most specialized species, diverging greatly from the genus mean; D. heermanni was the least specialized. This study provides new insights into morphological variation of North American keystone species, several of conservation interest, for example, D. heermanni berkeleyensis, D. h. dixoni, D. nitratoides brevinasus, and D. n. nitratoides. [ABSTRACT FROM AUTHOR]

This archaeological note proposes that the animal skull appearing on the Hesione Vase (Museum of Fine Arts Boston 63.420) and often identified as a Miocene giraffid belongs to an equid. The imagery of the sixth-century BCE vase is examined in relation to the iconographic tradition of the Lernaean Hydra and the ketos (sea monster). The paleogeography of the Corinthia and comparative osteology of the skull are considered. The possibility is raised that the skull belongs to a Plio-Pleistocene hipparionine equid, discovered in the Corinthia during clay collection in antiquity. 1 [ABSTRACT FROM AUTHOR]

In this study, we assessed the sexual dimorphism of the contemporary Japanese skull and established sex discriminant function equations based on cranial measurements using three-dimensional (3D) computed tomography (CT) images. The CT images of 263 corpses (142 males, 121 females) that underwent postmortem CT scanning and subsequent forensic autopsy were evaluated. Twenty-one cranial measurements were obtained from 3D CT reconstructed images, which extracted only bone data. We performed descriptive statistics and discriminant function analyses for the measurements. Nineteen measurements were significantly larger in males, suggesting sexual dimorphism of the Japanese skulls. Univariate discriminant function analyses using these measurements showed a sex classification accuracy of 57.8–88.2%, and bizygomatic breadth provided the highest correct prediction rate. Multivariate discriminant function analyses offered the most accurate model using seven variables with an estimation rate of 93.9%. Our results suggest that cranial measurements based on 3D CT images may help in the sex estimation of unidentified bodies in a contemporary Japanese population. [ABSTRACT FROM AUTHOR]

The article explores the considerations and challenges of administering neuraxial anaesthesia to parturients with intracranial pathology. Topics discussed include the management of obstetric anaesthesia in patients with intracranial hypertension, the potential risks associated with lumbar puncture, and the complexities of using regional anaesthesia in this clinical setting.

Background: Meningiomas are rare tumors in children compared with adults. Their main peculiarities are the frequent convexity or intraventricular location, the common association with neurofibromatosis-2 (NF-2) and the relatively high rate of aggressive and/or hyperostotic variants. Hyperostosis may complicate the surgical management. The goal of this paper is to provide an update on the main characteristics and the management of hyperostotic meningiomas. Case description: A 7-year-old girl was admitted to our department because of a long-lasting history of left frontal skull bulging. Neuroimaging examinations revealed a huge hyperostotic meningioma with bony invasion and infiltration of the superior sagittal sinus. Genetic tests were positive for NF-2. The tumor (atypical meningioma) was gross totally resected. During the same operation, a custom-made cranioplasty was realized with the help of a frame-based craniectomy. The patient is asymptomatic and under oncological follow-up. Discussion and conclusion: Although generally rare, hyperostotic meningiomas are relatively common in children and clinically demanding because of their large size, the possible aggressive behavior and the need of a cranioplasty as additional surgical step. Therefore, a careful preoperative surgical planning is required, taking into account that the extent of surgical resection is an important prognostic factor. The long-term outcome is good. [ABSTRACT FROM AUTHOR]

The evolution of unique morphological features can significantly constrain the subsequent phenotypic diversification of a clade. Bats show diverse skull shapes and are salient among mammals in their dramatic reorientation of major cranial features due to changes in the relative position of the rostrum with respect to the braincase (rostral flexion). Previous studies have suggested that rostral flexion evolved early in the history of bats in tandem with divergent echolocation modes. We directly quantified rostral flexion and integrated biomechanical modelling, morphometric, and comparative phylogenetic approaches to explore its functional and evolutionary consequences. We found that strong selection associated with echolocation mode explains the early evolution of rostral flexion in bats, with subsequent diversification at different rates within different echolocation emission types. We find extreme rostral flexion is associated with trade-offs in bite performance and overall evolutionary lability of cranial shape. The divergent evolution of rostral flexion across major bat lineages has thus been a major factor structuring the potential evolutionary pathways for the bat cranium. We further suggest that the early evolution of rostral flexion in bats biased the transitions to and from certain echolocation emission modes, and may have differentially affected the degree of dietary ecological diversification among bat clades. [ABSTRACT FROM AUTHOR]

Transcranial ultrasound imaging is a popular method to study cerebral functionality and diagnose brain injuries. However, the detected ultrasound signal is greatly distorted due to the aberration caused by the skull bone. The aberration mechanism mainly depends on thickness and porosity, two important skull physical characteristics. Although skull bone thickness and porosity can be estimated from CT or MRI scans, there is significant value in developing methods for obtaining thickness and porosity information from ultrasound itself. Here, we extracted various features from ultrasound signals using physical skull‐mimicking phantoms of a range of thicknesses with embedded porosity‐mimicking acoustic mismatches and analyzed them using machine learning (ML) and deep learning (DL) models. The performance evaluation demonstrated that both ML‐ and DL‐trained models could predict the physical characteristics of a variety of skull phantoms with reasonable accuracy. The proposed approach could be expanded upon and utilized for the development of effective skull aberration correction methods. [ABSTRACT FROM AUTHOR]

Objective: To predict the morbidity of sagittal suturectomy using preoperative computer tomographic measurement of frontal and parietal bone thickness in osteotomy sites. Design: Retrospective analysis. Setting: Tertiary children's hospital. Patients: Fifty infants with nonsyndromic, isolated sagittal craniosynostosis who underwent extended sagittal suturectomy from 2015–2022. Methods: Mean thickness of the frontal and parietal bone in regions of osteotomies were determined for each patient from preoperative CT images obtained within 30 days prior to suturectomy. The relationship between bone thickness (mm) and estimated blood loss (mL) was evaluated using Spearman's correlation and a multivariable model that adjusted for patient weight and surgery duration. The association between bone thickness and perioperative blood transfusion was evaluated using a multivariable logistic model controlling for patient weight and surgery duration. Main Outcome Measures: Estimated blood loss, perioperative blood transfusion. Results: Frontal and parietal bone thickness in the region of osteotomies were positively correlated with estimated blood loss (p < 0.01). After adjusting for patient weight and duration of operation, both parietal and frontal bone thickness were associated with intraoperative blood loss (R2 = 0.292, p = 0.002 and R2 = 0.216, p = 0.026). Thicker frontal and parietal bone in the line of osteotomies resulted in significantly higher odds of blood transfusion. Bone thickness in the line of parietal osteotomies was 76% accurate at identifying patients who would require blood transfusion (p = 0.004). Conclusions: Frontal and parietal bone thickness in the line of osteotomies is associated with blood loss and perioperative blood transfusion for sagittal suturectomy operations. [ABSTRACT FROM AUTHOR]

This study analyses an "eastern" mirror with a central loop, related to the Berjozovka-Carnuntum-Mödling type, which was recently discovered in Secuieni, Bacău County, Romania. Such mirrors, common among nomadic tribes, have been found mainly in the northern Caucasus and north, north-west of the Black Sea. It is thought that the nomads of Central Asia adopted them due to their frequent interactions with China. The mirrors made their way to Europe during the Migration Period, accompanying the eastward advance of the Alans and Hunnic tribes. Notably, they were found mainly in the Middle and Lower Danube region in the 5th century AD. Most of these mirrors were recovered from the graves of women, often with artificially deformed crania, buried with prestigious objects (such as large silver fibulae with semi-circular plates, Adlerfibeln, gold diadems, granulated earrings, beads, etc.). Only 12 such mirrors have been documented in Romania, and only one in the region of Moldavia (Romania, Region between Eastern Carpathians and Prut) in fragmentary form. The recent discovery of a mirror at Secuieni is therefore of great archaeological value, shedding light on the archaeological landscape of the Migration Period east of the Carpathians and far beyond, as far as China. [ABSTRACT FROM AUTHOR]

The urial (OOR‐ee‐əl; Ovis vignei), also known as the arkars or shapo, is a wild sheep native to Central and South Asia. It is listed as vulnerable on the International Union for Conservation of Nature (IUCN) Red List. Considering the importance of this breed in the world and its extinction, there is a need to determine the anatomy of the head area or any other disease such as fractures, dental, and infectious diseases. Five adult healthy male urial sheep were used, which were mature in terms of age. After preparation, the fresh alive sheep were immediately examined using a helical computed tomography scanner. The morphometry of the skull of this sheep was studied using RadiAnt application. The volume calculation was performed automatically using the software available on the CT scan system (Syngo MMWP VE40A software). The sinuses observed in the skull of this breed included frontal, maxillary, lacrimal, palatine, and sphenoidal sinuses. The height, length, and width of the skull were measured as 15.32 ± 0.05, 23.89 ± 0.08, and 12.57 ± 0.05 cm, respectively. According to the results obtained from the volume of different parts of the head in urial sheep, the nasal cavity and the oral cavity constitute 7% and 6% of the head volume, respectively. This ratio was calculated as 0.5% in the case of the inner and middle ears. Determining the anatomical structures and morphometric and volumetric characteristics of Urial sheep, which is one of the endangered Asian breeds, was of particular importance in order to prepare the head and skull atlas. [ABSTRACT FROM AUTHOR]

Background: Important neurovascular arteries, such as the auxiliary meningeal artery and mandibular nerve, travel through the foramen ovale, a crucial foramen in the middle cranial fossa that plays a crucial role in both diagnosis and surgery. Therefore, for proper therapy, diagnosis, and identification of foramen ovale-related disorders, it is critical to comprehend the morphometric and morphological differences in the foramen ovale. Aim: The purpose of this study was to evaluate the morphometry specifics and morphological differences in Indian individuals' foremen ovale. METHODS: The anatomical changes as well as the sizes and shapes of the foramen ovale in the skulls were assessed in the current radiography examination. 200 human skulls--100 male and 100 female--were evaluated for the study using computed tomography images. Results: The average foramen length, breadth, and distance from midline were 2.4563±0.51273, 4.895±10629, and 6.460±1.679 mm on the right side and 2.4288±0.60037, 4.810±1.0846, and 6.449±1.6689 mm on the left. Most research participants had oval foramen ovale shapes (47%), with round foramen ovale shapes observed in 31% of patients. None of the individuals had any spurs or other bony outgrowths. Male and female morphometric differences were statistically not significant (p>0.05). Conclusions: The current study comes to the conclusion that differences in the foramen ovale's morphology should be taken into account since they have substantial clinical anatomical variances for different surgical and diagnostic procedures. [ABSTRACT FROM AUTHOR]

Giraffe (Giraffa spp.) are among the most unique extant mammals in terms of anatomy, phylogeny, and ecology. However, aspects of their evolution, ontogeny, and taxonomy are unresolved, retaining lingering questions that are pivotal for their conservation. We assembled the largest known dataset of Giraffa skulls (n = 515) to investigate patterns of cranial variability using 3D geometric morphometrics. The results show distinct sexual dimorphism and divergent ontogenetic trajectories of skull shape for the north clade (G. camelopardalis antiquorum, G. c. camelopardalis, G. c. peralta, and G. reticulata) and the south clade (G. giraffa angolensis, G. g. giraffa, G. tippelskirchi tippelskirchi, and G. t. thornicrofti) which was further supported statistically. Discriminant functions found statistically significant cranial shape differences between all four Giraffa species, and in some cases also between subspecies of the same species. Our 3D morphometric analysis shows that the four genetically distinct Giraffa spp. also have distinct cranial morphologies, largely addressable to features of display (ossicones). Our results highlight the importance of focusing future giraffe conservation efforts on each taxon to maintain their unique characteristics and biodiversity in the wild. [ABSTRACT FROM AUTHOR]

Background: External ventricular drain (EVD) insertion is one of the most commonly performed neurosurgical procedures. Herein, we introduce a new concept of a cranial fixation device for insertion of EVDs, that reduces reliance on freehand placement and drilling techniques and provides a simple, minimally invasive approach that provides strong fixation to minimal thickness skulls. Methods: An experimental device for catheter insertion and fixation was designed and tested in both ex-vivo and in-vivo conditions to assess accurate cannulation of the ventricle and to test the strength of fixation to the skull. The ex-vivo experiments were conducted at Ben-Gurion University of the Negev (BGU) in Be'er Sheva, Israel. These experiments included functionality bench testing and pullout force measurements for the ball mechanism and catheter fixation. For the in-vivo experiments the fixation device was initially tested at the Cincinnati Children's Hospital Medical Center (CCHMC) in Cincinnati, Ohio on one day of life 1 (DOL 1) male control lamb. Additional experiments were conducted on 3 hydrocephalic DOL 0 lambs (1 male 2 female) at the Jesús Usón Minimally Invasive Surgery Centre (JUMISC) in Caceres, Spain. The hydrocephalic animal model used for this study was created with in utero intracisternal injection of BioGlue in fetal lambs. The catheter insertion trajectory was determined using MR imaging to assess the device's impact on the placement accuracy. The fixation device was evaluated on reaching the ventricle and enabling extraction of CSF for all 7 fixations placed. For 5 of the fixation devices, post-mortem pullout force was measured. The general functionality of the device was also evaluated. Results: In the experiments, 7/7 (100%) catheter trajectories successfully reached the ventricle without any apparent complications related to the device or the procedure. The cranial fixation device base demonstrated significant strength in withstanding an average pull-out force of 4.18kgf (STD 0.72, N = 5) without detachment from the subject's skull for all 5 devices included in this test. Additionally, the EVD catheter pull test was conducted with the addition of a safety loop which did not allow movement of the EVD to a force of 3.6kgf. At this force the catheter tore but did not release from its fixation point. Conclusion: The newly designed experimental device demonstrates initial proof of concept from ex vivo and in vivo testing. It appears suitable for accurate ventricular catheter placement and cranial fixation. [ABSTRACT FROM AUTHOR]

A total of 297 wolf skulls from the collection of the Central Forest State Biosphere Reserve were studied for the presence of trauma. Of these, 129 (43.4 ± 2.9%) skulls had trauma of various origins or a deformed sagittal crest. Aside from the sagittal crest, the level of trauma was 32.3 ± 2.7%. Based on the causes of origin, the types of trauma were divided into three groups: those received when preying on moose, those sustained during aggressive intraspecific contacts, and accidental. Complicated fractures of dental crowns predominate among accidental trauma. Moose preying trauma and intraspecific aggression are more common in subadult wolves than in adults, which can be attributed to the elimination of injured animals. The frequency of occurrence of accidental trauma, on the contrary, increases with age. The level of trauma serves as a population characteristic, indicating tension in the predator–prey system and the degree of intraspecific aggression. [ABSTRACT FROM AUTHOR]

In 2021 and 2022, archaeological surveys and major excavations were conducted at the Xuetang Liangzi site in Areas B, C, and E. These efforts uncovered archaeological remains that include a complete sequence of Paleolithic cultures in southern China. The history of prehistoric human activity at the site spans more than one million years, covering the early to late Paleolithic period. The No. 3 skull of Yunxian Man, unearthed from Layer 3 in Area B, dates to approximately one million years ago and is the best-preserved hominin cranium found on the Eurasian continent of its period. [ABSTRACT FROM AUTHOR]

Utilising segmental data of MHIN-UNSL-GEO-V 465, we extend and re-evaluate previous observations on the morphology of the macraucheniid Oxyodontherium zeballosi comparing with additional micro and medical CT evidence from published data on Litopterna and other South American Native Ungulates (SANU). This new anatomical information includes qualitative and quantitative data on cranial pneumatization, nasal and encephalic cavities, and body mass estimates. The calculated Encephalization Quotients for MHIN-UNSL-GEO-V 465 range between 0.32 and 0.43, which are relatively low compared to other macraucheniids. The neopallial height ratio indicates a less expanded neopallial surface than in Huayqueriana and other Miocene SANU, and a higher ratio than several early ungulates. Our data reveal that O. zeballosi shares characteristics with the protolipternid cf. Miguelsoria parayirunhor, such as a shallow rostral tympanic process and a bulkier pars canalicularis of the inner ear. Although O. zeballosi shows less pneumatic spaces than other macraucheniids, it does show an important degree of pneumatization in the anterior portion of the caudal cranium, especially affecting frontals, parietals, and the alisphenoid. Finally, the estimated body mass of O. zeballosi is around 122–180 kg. This study increases the knowledge of the internal cranial anatomy of litopterns providing potentially valuable characters for future phylogenetic analyses. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 infection is associated with long-lasting neurological symptoms, although the underlying mechanisms remain unclear. Using optical clearing and imaging, we observed the accumulation of SARS-CoV-2 spike protein in the skull-meninges-brain axis of human COVID-19 patients, persisting long after viral clearance. Further, biomarkers of neurodegeneration were elevated in the cerebrospinal fluid from long COVID patients, and proteomic analysis of human skull, meninges, and brain samples revealed dysregulated inflammatory pathways and neurodegeneration-associated changes. Similar distribution patterns of the spike protein were observed in SARS-CoV-2-infected mice. Injection of spike protein alone was sufficient to induce neuroinflammation, proteome changes in the skull-meninges-brain axis, anxiety-like behavior, and exacerbated outcomes in mouse models of stroke and traumatic brain injury. Vaccination reduced but did not eliminate spike protein accumulation after infection in mice. Our findings suggest persistent spike protein at the brain borders may contribute to lasting neurological sequelae of COVID-19. [Display omitted] • SARS-CoV-2 spike protein persists in the skull-meninges-brain axis in COVID-19 patients • Spike protein is sufficient to induce brain pathological and behavioral changes in mice • Spike protein enhances brain vulnerability and exacerbates neurological damage in mice • mRNA vaccines reduce, but do not eliminate, the spike burden SARS-CoV-2 infection can lead to long-lasting neurological sequelae, but underlying mechanisms are unclear. Rong et al. report that SARS-CoV-2 spike protein persists in the skull-meninges-brain axis, inducing inflammation, neurodegeneration-related changes, and increasing the brain's vulnerability to further injury. [ABSTRACT FROM AUTHOR]

Objective: This study investigates the impact of non-standard positioning on the accuracy of 6D-skull tracking using dual-panel imaging systems. It explores whether positioning patients' heads at various angles during intracranial lesion treatment affects the accuracy of the CyberKnife 6D-skull tracking system. Materials and methods: A heterogeneous density skull phantom was used to simulate various patient skull positioning angles. To accurately compare 6D-skull tracking and fiducial tracking, their center coordinates were pre-set to be identical in the treatment plan. The phantom was positioned using fiducial tracking, and the offset value recorded. The system was then switched to 6D-skull tracking to observe the corresponding offset. The difference between the two tracking methods was calculated, and a paired-sample T-test was conducted to assess statistical significance across different angles. Additionally, the gamma passing rate (criteria: 3%/3mm) was employed to quantitatively delineate dosimetric disparities attributable to positional variations. Results: Paired sample T-tests on the deviations between rotational and translational parameters of fiducial tracking and skull tracking under identical conditions revealed no statistically significant differences between the methods across all selected angles. The minimal deviations and lack of statistical significance demonstrate that both tracking methods are equivalent in skull positioning. Furthermore, the gamma passing rate analysis showed that in all tested conditions, the rates exceeded 95%, which aligns with clinical requirements. This high passing rate indicates a high degree of dosimetric accuracy and consistency between the two tracking methods, providing robust assurance of treatment precision in skull positioning. Conclusion: Since fiducial tracking is not affected by patient or phantom positioning, this study compares the registration results of 6D-skull tracking with fiducial tracking under the same conditions. The results show minimal deviations and no statistically significant differences, indicating that 6D-skull tracking is not dependent on the skull's positioning angle. Furthermore, the gamma passing rate analysis was conducted to quantitatively assess the dosimetric differences arising from variations in patient positioning. Our results demonstrated that under all tested conditions, the gamma passing rates exceeded the clinically accepted threshold of 95%, confirming the clinical adequacy of both tracking methods in maintaining treatment precision. In clinical practice, patients do not need to maintain a strict supine position; the algorithm can accurately perform registration even if patients need to rotate their heads or lie prone. Clinical recommendations should prioritize patient comfort and safety without imposing overly strict requirements. [ABSTRACT FROM AUTHOR]

The evolution and ecomorphology of rodent craniomandibular apparatus have been extensively studied at a broad spatial scale. However, the question of how phenotypes and developmental instability interact with ecological pressures in human‐modified landscapes has been less explored. In this study, we test the influence of evolutionary history, diet, and habitat use on skull and mandible shape variation within a rodent community composed of eight cricetid species from an agroecosystem in central Argentina. We used geometric morphometrics, phylogenetic relationships, and ecological specializations in diet and habitat use to test the interplay between these factors. Our results indicated a strong phylogenetic signal for the symmetric components of the skull shape, but not for the mandible or asymmetric shapes. The strict insectivorous Oxymycterus rufus was the most phenotypically diverged within the rodent community. In general, more generalist species, both in terms of diet and habitat use, presented more phenotypic disparity (diversity) than specialists (e.g., strict insectivorous and natural and semi‐natural specialists) in craniomandibular shape variation. Dietary generalists and non‐strict granivores presented a tendency to show more skull asymmetric variation than non‐strict insectivores. These results suggest that generalist species exhibit higher levels of variation compared to specialist species, likely due to their wider range of responses to environmental stress. In cricetid species with similar ecological preferences, coexistence may thus be facilitated by morphological partitioning and developmental instability canalization based on dietary differences. [ABSTRACT FROM AUTHOR]

Chronic osteomyelitis of the skull base is a commonly reported pathology in existing scientific literature, but chronic osteomyelitis of the skull vault (COSV) is a rarely documented disease. We report the case of a 38 years old Afghan male with a presenting complaint of irregular swelling on the skull vault for six months. The patient had a history of head trauma one year back with a compound depressed fracture which had been surgically managed then. Physical examination revealed a 15 x 15 cm hard, immobile swelling with an old scar mark over the scalp. Neuroimaging was consistent with diffuse, bilateral frontoparietal swelling of bony origin, sparing underlying brain parenchyma. Surgically excision of the lesion was done through a bicoronal skin flap and cranioplasty done at the same time. Histological findings of the specimen reported chronic osteomyelitis. However, microbiology revealed no growth in culture. Patient was discharged on the second postoperative day uneventfully. This case turns minds into keeping skull vault osteomyelitis as differential diagnosis besides other spontaneous bony lesions; e.g. fibrous dysplasia, osteoma and giant cell tumours. [ABSTRACT FROM AUTHOR]

Introduction: The purpose of this study was to evaluate the use of a novel imaging modality, digital tomosynthesis (DT), for identification of predefined anatomic dental and maxillomandibular structures in dogs. Methods: DT images were compared to conventional intraoral dental radiography (DR) for the diagnostic yield regarding the presence and quality of visualization of 35 structures. DT imaging and full mouth DR were obtained on 16 canine cadaver heads and a semi-quantitative scoring system was used to characterize the ability of each imaging method to identify the anatomic structures. Results: The results demonstrated that each imaging modality, and orientation, was superior for certain anatomic structures. Discussion: Overall, although one modality did not prove superior to the other, digital tomosynthesis appears to be an appropriate novel tool for identification of specific anatomic structures in the dog skull. [ABSTRACT FROM AUTHOR]

Introduction and Objectives: Skull vibration-induced nystagmus (SVIN) has become a validated tool for evaluating the vestibular function. The presence of SVIN is a useful indicator of the asymmetry of vestibular function between the two ears. In unilateral vestibular loss, a 100 Hz bone-conducted vibration given to either mastoid immediately causes a primarily horizontal nystagmus. The aim of this study is to review the usefulness of this tool in different clinical situations according to the results published. Methods: We performed an electronic search using PubMed and BVS. Eleven studies were discussed. Results: A progressive linear relationship has been identified between the slow-phase velocity (SPV) of SVIN determined using a 100 Hz skull vibrator and the gain difference (healthy ear/affected ear) measured by video head impulse test (vHIT). The SPV of SVIN may be more sensitive than vHIT in identifying the recovery of vestibular function following intratympanic gentamicin (ITG) administration. A link between a reduction in SPV and the likelihood of vertigo episodes in patients with MD who have been treated with intraympanic gentamicin (ITG) has been illustrated. SVIN in superior canal dehiscence (SCD) patients has greater sensitivity than the air-conducted Tullio phenomenon (ACTP) or the Hennebert sign. SVIN can be combined with vHIT to reveal vestibular asymmetry in nonprogressive vestibular schwannomas. An upbeating SVIN may reveal superior branch vestibular neuritis. Vibration-induced downbeat nystagmus should be added to the list of central vestibular signs and is likely due to cerebellar dysfunction. Conclusions: SVIN has become an interesting screening tool for diagnosing or during the follow-up of many different vestibular pathologies. [ABSTRACT FROM AUTHOR]

During the radiographic examination, the cranium orientation varies not only individually but also within the same subject, in different imaging sessions. Knowing how changes in the orientation of the cranium influences cervical sagittal alignment during the radiographic examination of the cervical spine can aid clinicians in the accurate evaluation for cervical sagittal alignment in clinical practice. To radiographically examine the influence of cranium orientation on cervical sagittal alignment during radiographic examination in an asymptomatic cohort. A prospective radiographic study. Eighty asymptomatic volunteers (mean age, 40.4 years; 50.0% male) were enrolled. Cervical sagittal parameters including the regional slope (C1 slope, C2 slope, C5 slope, C7 slope, and T1 slope), Cobb angle (O–C1 angle, C1–C2 angle, C2–C5 angle, C5–C7 angle, and C7–T1 angle), and cranial/cervical offset (sella turcica tilt [ST tilt] and C2 tilt). In all participants, standing lateral radiographs of the cervical spine were taken in 3 forward-gazing positions: anteverted-cranium (AC) position; neutral-cranium (NC) position; and retroverted-cranium (RC) position. Cervical sagittal parameters, including the regional slope, Cobb angle, and cranial/cervical offset, in these 3 positions were statistically compared. The C1 and C2 slopes were anteverted and retroverted in the AC and RC positions, respectively, compared to those in the NC position. The C5 slope, C7 slope, and T1 slope were constant among the 3 positions. In O–C2 and C2–C5, statistically significant differences in the regional Cobb angles were identified among the 3 positions; however, there were no significant differences in the C5–C7 or C7–T1 segments. Cranial and cervical offsets of ST tilt and C2 tilt increased and decreased when the cranium was anteverted and retroverted, respectively. The current study suggests that the adjustment of the cranium orientation when taking cervical spine radiographs is mainly controlled at the upper cervical spine of the O–C2 segment in an asymptomatic cohort. On radiograph, alignment in the upper cervical segment of O–C2 changes; accordingly, the middle cervical segment of C2–C5 can change during the adjustment of cranium orientation. However, alignment in the lower cervical segment of C5–C7 and the cervicothoracic junction of C7–T1 remains constant. Further, cranial/cervical offset increases and decreases when the cranium is anteverted and retroverted, respectively. Our results can help the accurate evaluation of cervical sagittal alignment on plain radiographs in clinical practice. [ABSTRACT FROM AUTHOR]

Mourasuchus is one of the most well-known components of the notable South American crocodylomorph fauna of the Cenozoic. There has been a recent renewed interest in the taxonomy of Mourasuchus, but some issues remained. This study addressed the taxonomic problems of the genus, concluding that there are four valid species: M. amazonensis (Price 1964), M. atopus , M. arendsi (Bocquentin-Villanueva 1984) and M. pattersoni (Cidade et al. 2017). M. arendsi may be a junior synonym of M. atopus, but this can only be evaluated through an eventual reanalysis of the ventral aspect of the skull of the holotype of M. arendsi. The specimens LACM-160157, UFAC-1424 and UFAC-5883 may either belong to M. amazonensis or represent a new species, which can be evaluated only through an eventual reanalysis of the dorsal aspect of the skull of the holotype of M. amazonensis. Mourasuchus nativus is considered a nomen dubium as its holotype is indistinguishable from at least two other Mourasuchus species: M. arendsi and either M. amazonensis or the possible new species represented by LACM-160157, UFAC-1424 and UFAC-5883. This study stresses the importance of taxonomic accuracy to comprehend fossil faunas, including remarkably diverse ones like South American cenozoic crocodylomorphs. [ABSTRACT FROM AUTHOR]

The transverse dimensions of internasal and nasopremaxillary sutures in rats were assessed at different ages and following different dietary functional demands.Eighty‐four male Wistar rats were divided into two groups fed either a hard or a soft diet from 4 weeks of age, and sacrificed at 4 weeks (baseline: n = 12),16 weeks (n = 24), 26 weeks (n = 24), or 38 weeks (n = 24) of age. High‐resolution micro‐computed tomograms of the internasal and left nasopremaxillary sutures were obtained with 10 µm voxel size and 5 × 5 mm field of view. The endocranial and ectocranial suture widths, the mean suture width, and the suture height were measured. Linear regression analysis was used to estimate the effects of age and type of diet on suture dimensions. Internasal and nasopremaxillary suture dimensions were influenced by age, with a generally lower width and a larger height in the older animal. Regarding diet consistency, internasal suture widths were on average larger in the hard‐diet group (e.g., mean suture width 43 µm in the hard‐ versus 30 µm in the soft‐diet group at 26 weeks). In conclusion, the internasal and nasopremaxillary sutures tend to become narrower with age, while being influenced by masticatory functional demands. [ABSTRACT FROM AUTHOR]

X‐ray Computed Tomography (CT) images are widely used in various fields of natural, physical, and biological sciences. 3D reconstruction of the images involves segmentation of the structures of interest. Manual segmentation has been widely used in the field of biological sciences for complex structures composed of several sub‐parts and can be a time‐consuming process. Many tools have been developed to automate the segmentation process, all with various limitations and advantages, however, multipart segmentation remains a largely manual process. The aim of this study was to develop an open‐access and user‐friendly tool for the automatic segmentation of calcified tissues, specifically focusing on craniofacial bones. Here we describe BounTI, a novel segmentation algorithm which preserves boundaries between separate segments through iterative thresholding. This study outlines the working principles behind this algorithm, investigates the effect of several input parameters on its outcome, and then tests its versatility on CT images of the craniofacial system from different species (e.g. a snake, a lizard, an amphibian, a mouse and a human skull) with various scan qualities. The case studies demonstrate that this algorithm can be effectively used to segment the craniofacial system of a range of species automatically. High‐resolution microCT images resulted in more accurate boundary‐preserved segmentation, nonetheless significantly lower‐quality clinical images could still be segmented using the proposed algorithm. Methods for manual intervention are included in this tool when the scan quality is insufficient to achieve the desired segmentation results. While the focus here was on the craniofacial system, BounTI can be used to automatically segment any hard tissue. The tool presented here is available as an Avizo/Amira add‐on, a stand‐alone Windows executable, and a Python library. We believe this accessible and user‐friendly segmentation tool can benefit the wider anatomical community. [ABSTRACT FROM AUTHOR]

The finding also represents the first detection of this trematode on the Balkan Peninsula. The study was conducted between 2014 and 2023. Nineteen road-killed polecats, mainly from southern Bulgaria, were examined. A four-year-old male polecat road-killed near Chepelare, a town in the Somlyan Province in the Rhodope Mountains, was infested with six adult Troglotrema acutum within its frontal sinus. The skull exhibited only weakly developed lesions. The prevalence of 5.26% observed in this sample was lower than values reported from other European countries. This finding extends the known southeastern distribution range of T. acutum by over 700 km. [ABSTRACT FROM AUTHOR]

Peromyscus sonoriensis is a widespread species ranging from southern Texas to the Yukon, from the Mississippi to the Pacific. Because of this extensive range, there are substantial differences in morphology due to variation in temperature, precipitation, and habitat. We used 2 data sets (n = 4,840 and n = 20,175) to study morphological differences of their crania and appendages. Consistent with Allen's rule (shorter appendages with colder temperature), both data sets show a strong, positive, correlation between tail length and the average January temperature. However, there was an equally strong, but negative, correlation between tail length and average July temperature. We observed similar results for feet and crania. Ear length had a significant negative correlation with July average temperature but no correlation with January average temperature. When we controlled for temperature, cranial and appendage length increased with latitude, which was opposite of what we expected. Furthermore, longitude had a strong impact as mice trapped further west had longer appendages. When divided into habitats, forest deer mice are more likely than prairie or desert deer mice to demonstrate morphological responses to differences in climate, location, and year trapped. Our results show that P. sonoriensis exhibit notable morphological variation linked to location, habitat, and climate. [ABSTRACT FROM AUTHOR]

Background: In zooarchaeology, reference collections are essential for identifying skeletal remains and for predicting measurements of living animals. To date, the archaeozoological studies in Algeria are still limited and morphometric reference datasets of local breeds are yet to be established. This study aimed to reveal the correlations between measurements of living animals and their skulls. Methods: A total of 30 females of the Ouled Djellal Algerian White Arab breed were analyzed: 15 adults and 15 young adults. Eight external body measurements were taken before slaughter and the live weight was estimated. After slaughter, the heads were collected, meticulously cleaned, weighed and measured. Sixteen craniometric measurements were taken and two indices were calculated. Result: The differences between the mean values of young adults and adults were not statistically significant (p>0.05), except for wither height, naso-dental oblique length (CL31), greatest palatal breadth (CB14), greatest breadth across the premaxillae (CB18) and least height of the occipital (CH5). Young adults have a higher neurocranium and are more massive, whereas adults have a wider viscerocranium. Correlations between cranial and external measurements were partially significant, predominantly in adults. The strongest correlation was observed between the thoracic perimeter and condylobasal length (p<0.0001). These results provide a new reference dataset for archaeozoology. [ABSTRACT FROM AUTHOR]

Purpose: Combined micro-PET/CT scanners are widely employed to investigate models of brain disorders in rodents using PET-based coregistration. We examined if CT-based coregistration could improve estimates of brain dimensions and consequently estimates of nondisplaceable binding potential (BPND) in rodent PET studies. Procedures: PET and CT scans were acquired on 5 female and 5 male CD-1 mice with 3-[18F]fluoro-5-(2-pyridinylethynyl)benzonitrile ([18F]FPEB), a radiotracer for the metabotropic glutamate receptor subtype 5 (mGluR5). In the proposed PET/CT (PTCT) approach, the tracer-specific standard volume was dimension-customized to each animal using the scaling factors from CT-to-standard CT coregistration to simplify PET-to-standard PET coregistration (i.e., 3 CT- and 6 PET-derived parameters). For comparison, conventional PET-based coregistration was performed with 9 (PT9) or 12 (PT12) parameters. PET frames were transferred to the standard space by the three approaches (PTCT, PT9, and PT12) to obtain regional time-activity curves (TACs) and BPND in 14 standard volumes of interest (VOIs). Lastly, CT images of the animals were transferred to the standard space by CT-based parameters from PTCT and with the scaling factors replaced with those from PET-based PT9 to evaluate agreement of the skull to the standard CT. Results: The PET-based approaches showed various degrees of underestimations of scaling factors in the posterior-anterior-direction compared to PTCT, which resulted in negatively proportional overestimation of radioactivity in the cerebellum (reference region) up to 20%, and proportional, more prominent underestimation of BPND in target regions down to -50%. The skulls of individual animals agreed with the standard skull for scaling factors from PTCT but not for the scaling factors from PT9, which suggested inaccuracy of the latter. Conclusions: The results indicated that conventional PET-based coregistration approaches could yield biased estimates of BPND in proportion to errors of brain dimensions when applied to tracers for which the cerebellum serves as reference region. The proposed PTCT provides evidence of a quantitative improvement over PET-based approaches for brain studies using micro-PET/CT scanners. [ABSTRACT FROM AUTHOR]

Intraoperative neurophysiological monitoring (IONM) is instrumental in mitigating neurological deficits following cranial and spinal procedures. Despite extensive research on IONM's ability to recognize limb-malposition-related issues, less attention has been given to other secondary neural injuries in cranial surgeries. A comprehensive multimodal neuromonitoring approach was employed during a left frontal craniotomy for tumor resection. The electronic medical record was reviewed in detail in order to describe the patient's clinical course. The patient, a 46-year-old female, underwent craniotomy for excision of a meningioma. Deteriorations in somatosensory evoked potential and transcranial motor evoked potential recordings identified both a mal-positioned limb as well as an infiltrated intravenous (IV) line in the arm contralateral to the surgical site. The IONM findings for the infiltrated IV were initially attributed to potential limb malposition until swelling and blistering of the limb were appreciated and investigated. The timely identification and management of the infiltrated IV and adjustment of limb positioning contributed to the patient's recovery, avoiding fasciotomy, with no postoperative neurological deficits. This case is the first published demonstration of the utility of IONM in detecting IV infiltration. This early recognition facilitated early intervention, saving the patient from a potential fasciotomy and enabling their recovery with no postoperative neurological deficits. The findings from this single case highlight the necessity for vigilant and dynamic application of IONM techniques to enhance patient safety and outcomes in neurosurgical procedures. Further research is needed to explore broader applications and further optimize the detection capabilities of IONM. [ABSTRACT FROM AUTHOR]

Knowledge of Didelphidae taxonomy and diversity has increased steadily over the last decades, mainly due to increasing collection efforts and revisionary works. Yet, especially for mouse opossums, a proper appraisal of morphological variation is still incipient. Thylamys karimii occurs in the Brazilian biomes of Caatinga and Cerrado, and specimens with two different shades of dorsal coloration (brown and gray) were recently documented in sympatry in the Parque Nacional (PARNA) do Catimbau (Caatinga biome). We used qualitative and morphometric data from skulls and skins (n = 7 from PARNA Catimbau and n = 26 from other localities) to compare these two coat color morphotypes and characterize the morphological diversity and taxonomic status of the Caatinga populations. We used Student's t-tests to compare sexes and morphotypes' measurements. We found at least three well-defined coat color morphotypes distinguishable by dorsal and ventral coloration and not restricted to PARNA Catimbau. Variation of the other morphological traits suggests that these morphotypes are more likely a case of intraspecific variation in the Brazilian northeastern region. Morphometric differences, particularly between coat color morphotypes, might be better elucidated in larger samples. Additionally, these specimens represent an important extension of the species' known distribution reaching the Atlantic Forest borders. [ABSTRACT FROM AUTHOR]

Defining species within the Canidae family is challenging due to morphological convergence, behavioral plasticity, traditional taxonomic limitations, and possible hybridisation. This challenge is timely with the recent population and range expansion of the golden jackal (Canis aureus). Exploring their morphological data and sexual dimorphism is essential for identifying factors driving their success in new habitats. The proven hybridization of golden jackals with dogs and wolves may affect species description, population dynamics, and genetic diversity, impacting conservation strategies. This study, for the first time, conducts a morphometric analysis of golden jackals in Somogy County, Hungary, to prove sexual size dimorphism (SSD) in body and skull and sexual shape dimorphism (SShD) in skull across juvenile and adult age groups. 719 golden jackals (362 females and 357 males) were collected between January 2021 and January 2023. Descriptive statistics revealed significant SSD in body and skull measurements among both age groups, with males generally larger than females, particularly in body mass (11.72% in juveniles and 13.37% in adults). Most skull dimensions differed significantly between sexes and age groups, except for foramen magnum height, foramen magnum width, and postorbital breadth among juveniles and foramen magnum height and postorbital breadth among adults. We used principal component analyses (PCA) on raw dimension data and the log shape ratio method to extract shape information. Linear discriminant analysis (LDA) explored skull SShD between sexes. Notably, our study achieved over 71% accuracy in sex classification, illustrating the clear presence of SShD of the skull in golden jackals across both age groups. Our study provides a comprehensive database of golden jackals in the overpopulated Hungarian habitat, which will be helpful for further research on ecology, behavior, and conservation management. [ABSTRACT FROM AUTHOR]

Purpose: Calvarial dermoid and epidermoid cysts are benign lesions common in pediatric neurosurgery. Diagnosis is primarily clinical, with frequent but inconsistent use of imaging. Dermoids have been shown to possess distinct sonographic features, but ultrasound (US) remains underutilized in their management. The purpose of this study is to investigate the independent reliability of US in managing pediatric calvarial dermoids and distinguishing them from other calvarial lesions. Methods: A retrospective review of consecutive patients ≤ 21 years of age with surgically resected calvarial masses between 2017–2024 was performed. Demographic, clinical, and imaging data were analyzed. Pearson chi-squared tests were used for comparison of categorical variables and a binomial linear model was generated controlling for age, lesion tenderness, growth, and suture location. Results: Fifty-nine patients with 61 lesions (31 in females; median age 13 months) were included. Dermoids were more common in younger patients (median age 12 months), along suture lines, and were less likely to present with tenderness (p < 0.001) or rapid growth (p = 0.003). Ultrasound was used in 83% of cases and was the sole imaging modality in 33%. On multivariate analysis, suture location was a significant positive predictor of a dermoid diagnosis (OR = 8.08, 95% CI = 1.67–44.18), while rapid growth was a significant negative predictor (OR = 0.08, 95% CI = 0.003–0.80). Conclusion: Ultrasound presents a sensitive and reliable method for the evaluation of most pediatric calvarial lesions, especially dermoid cysts, and warrants being part of standard workup. With appropriate patient selection, US obviates the need for additional imaging in pediatric patients. [ABSTRACT FROM AUTHOR]

Background: Encephalocele represent a group of disorders which is characterised by extracranial herniation of the leptomeninges, brain, and CSF through a structural defect in the cranium. They are usually associated with other intracranial anomalies which may impact the neurological development. Aim: This study aimed to assess the predictors of neurological development of patients undergone surgical excision of occipital encephalocele. Methods: All patients with occipital encephaloceles operated over the last decade (2012–2022). The sac size, presence of hydrocephalous, and associated anomalies were noted. The biopsy of these patients were reviewed and categorised as those which contains mature neural tissue and those without. The neurological outcomes were assessed by social, language, cognitive, and motor milestone and has been stratified into no delay, mild (1 of 4), moderate (2 or 3 of 4), and severe development delay (4 of 4). Results: Total of 35 patients were included with median age of 10 months (IQR = 5–20 months). Fifteen (42.9%) patients had sac size of ≥ 5 cm, and 23 (65.7%) patients had mature neural tissues on biopsy. The median follow-up period was 6.4 years (IQR = 4.38–10.65) years. Seventeen (49.6%) patients had moderate to severe developmental delay. The sac size of ≥ 5 cm (AOR = 33.5; 95%CI = 3.35–334.8) (p = 0.003) and presence of mature neural content in the sac (AOR = 13.32; 95%CI = 1.1–160.36) (p = 0.041) were associated with significant neurodevelopmental delay. Conclusion: The presence of a large sac of ≥ 5 cm and the presence of mature neural tissues on histopathological specimen of patients with encephalocele point towards the possibility of poor neurological development. [ABSTRACT FROM AUTHOR]