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1.
Cell Death Dis ; 15(6): 420, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886383

RESUMO

The regeneration of the mammalian skeleton's craniofacial bones necessitates the action of intrinsic and extrinsic inductive factors from multiple cell types, which function hierarchically and temporally to control the differentiation of osteogenic progenitors. Single-cell transcriptomics of developing mouse calvarial suture recently identified a suture mesenchymal progenitor population with previously unappreciated tendon- or ligament-associated gene expression profile. Here, we developed a Mohawk homeobox (MkxCG; R26RtdT) reporter mouse and demonstrated that this reporter identifies an adult calvarial suture resident cell population that gives rise to calvarial osteoblasts and osteocytes during homeostatic conditions. Single-cell RNA sequencing (scRNA-Seq) data reveal that Mkx+ suture cells display a progenitor-like phenotype with expression of teno-ligamentous genes. Bone injury with Mkx+ cell ablation showed delayed bone healing. Remarkably, Mkx gene played a critical role as an osteo-inhibitory factor in calvarial suture cells, as knockdown or knockout resulted in increased osteogenic differentiation. Localized deletion of Mkx in vivo also resulted in robustly increased calvarial defect repair. We further showed that mechanical stretch dynamically regulates Mkx expression, in turn regulating calvarial cell osteogenesis. Together, we define Mkx+ cells within the suture mesenchyme as a progenitor population for adult craniofacial bone repair, and Mkx acts as a mechanoresponsive gene to prevent osteogenic differentiation within the stem cell niche.


Assuntos
Diferenciação Celular , Proteínas de Homeodomínio , Osteogênese , Crânio , Animais , Camundongos , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Osteogênese/genética , Crânio/metabolismo , Osteoblastos/metabolismo , Osteoblastos/citologia , Suturas Cranianas/metabolismo , Células-Tronco/metabolismo , Células-Tronco/citologia , Biomarcadores/metabolismo
2.
Proc Biol Sci ; 291(2025): 20240654, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38889789

RESUMO

The morphology and biomechanics of infant crania undergo significant changes between the pre- and post-weaning phases due to increasing loading of the masticatory system. The aims of this study were to characterize the changes in muscle forces, bite forces and the pattern of mechanical strain and stress arising from the aforementioned forces across crania in the first 48 months of life using imaging and finite element methods. A total of 51 head computed tomography scans of normal individuals were collected and analysed from a larger database of 217 individuals. The estimated mean muscle forces of temporalis, masseter and medial pterygoid increase from 30.9 to 87.0 N, 25.6 to 69.6 N and 23.1 to 58.9 N, respectively (0-48 months). Maximum bite force increases from 90.5 to 184.2 N (3-48 months). There is a change in the pattern of strain and stress from the calvaria to the face during postnatal development. Overall, this study highlights the changes in the mechanics of the craniofacial system during normal development. It further raises questions as to how and what level of changes in the mechanical forces during the development can alter the morphology of the craniofacial system.


Assuntos
Força de Mordida , Crânio , Lactente , Humanos , Fenômenos Biomecânicos , Crânio/anatomia & histologia , Pré-Escolar , Tomografia Computadorizada por Raios X , Análise de Elementos Finitos , Feminino , Masculino , Mastigação , Adaptação Fisiológica , Recém-Nascido , Estresse Mecânico , Músculos da Mastigação/fisiologia
3.
Nat Commun ; 15(1): 4575, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834586

RESUMO

Bone regeneration requires a well-orchestrated cellular and molecular response including robust vascularization and recruitment of mesenchymal and osteogenic cells. In femoral fractures, angiogenesis and osteogenesis are closely coupled during the complex healing process. Here, we show with advanced longitudinal intravital multiphoton microscopy that early vascular sprouting is not directly coupled to osteoprogenitor invasion during calvarial bone regeneration. Early osteoprogenitors emerging from the periosteum give rise to bone-forming osteoblasts at the injured calvarial bone edge. Microvessels growing inside the lesions are not associated with osteoprogenitors. Subsequently, osteogenic cells collectively invade the vascularized and perfused lesion as a multicellular layer, thereby advancing regenerative ossification. Vascular sprouting and remodeling result in dynamic blood flow alterations to accommodate the growing bone. Single cell profiling of injured calvarial bones demonstrates mesenchymal stromal cell heterogeneity comparable to femoral fractures with increase in cell types promoting bone regeneration. Expression of angiogenesis and hypoxia-related genes are slightly elevated reflecting ossification of a vascularized lesion site. Endothelial Notch and VEGF signaling alter vascular growth in calvarial bone repair without affecting the ossification progress. Our findings may have clinical implications for bone regeneration and bioengineering approaches.


Assuntos
Regeneração Óssea , Células-Tronco Mesenquimais , Neovascularização Fisiológica , Osteogênese , Crânio , Animais , Regeneração Óssea/fisiologia , Camundongos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Masculino , Receptores Notch/metabolismo , Receptores Notch/genética , Camundongos Endogâmicos C57BL , Transdução de Sinais , Feminino , Angiogênese
4.
Anat Histol Embryol ; 53(4): e13064, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38841825

RESUMO

There are different strains of laboratory mouse used in many different fields. These strains differ anatomically. In order to determine these anatomical differences, shape analysis was conducted according to species. CD-1, C57bl/6 and Balb-c strains were preferred to study these differences. Forty-eight adult mouse strains belonging to these strains were utilized. The bones were photographed and geometric morphometry was applied to these photographs. Principal Component Analysis was applied to determine shape variations. In Principal component 1 for cranium, CD-1 and C57bl/6 strain groups showed different shape variations, while Balb-c strain group showed similar shape variations to the other strain groups. Principal Component 1 for the mandible separated the CD-1 and C57bl/6 strain groups in terms of shape variation. Principal Component 2 explained most of the variation between the C57bl/6 and CD-1 lineage groups. In PC1 for molars, the CD-1 group showed a different shape variation from the other groups. Mahalanobis distances and Procrustes distances were measured using Canonical variance analysis to explain the differences between the lineage groups. These measurements were statistically significant. For cranium, in canonical variate 1, CD-1 group of mouse and Balb-c group of mouse were separated from each other. In canonical variate 2, C57bl/6 group of mouse were separated from the other groups. For mandible, Balb-c group of mouse in canonical variate 1 and CD-1 group of mouse in canonical variate 2 were separated from the other groups. For molars, CD-1 group of mouse in canonical variate 1 and Balb-c group of mouse in canonical variate 2 were separated from the other groups. It was thought that these anatomical differences could be caused by genotypic factors as well as dietary differences and many different habits that would affect the way their muscles work.


Assuntos
Mandíbula , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Crânio , Animais , Crânio/anatomia & histologia , Camundongos/anatomia & histologia , Mandíbula/anatomia & histologia , Camundongos Endogâmicos BALB C/anatomia & histologia , Camundongos Endogâmicos C57BL/anatomia & histologia , Dente/anatomia & histologia , Análise de Componente Principal , Especificidade da Espécie , Masculino
5.
J Craniofac Surg ; 35(4): 1080-1083, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38829144

RESUMO

BACKGROUND: Titanium mesh cranioplasty is the most common strategy for the repair of skull defects. However, as the frequency of cranioplasty increases, the incidence of titanium mesh exposure following cranioplasty increases as well. This study aimed to investigate the methods and outcomes of plastic surgery in the management of titanium mesh exposure following cranioplasty. METHODS: Patients with titanium mesh exposure following cranioplasty were retrospectively selected from January 2016 to August 2021. Titanium mesh exposure was corrected with reconstructive plastic surgery, including skin grafting, expander insertion, partial removal of the exposed mesh, replacement of the mesh, or flap transplantation. RESULTS: This study included 21 patients with titanium mesh exposure with surgical site infection and a variant of scalp deformity. The age of the patients ranged from 18 to 74 years, with the mean age being 54 years. All patients underwent reconstructive plastic surgery and exhibited complete wound healing. The follow-up period ranged from 17 to 90 months. One patient experienced titanium mesh re-exposure and subsequently underwent an additional procedure for the partial removal of the exposed mesh. No serious complications were observed postoperatively. CONCLUSION: Reconstructive plastic surgery can facilitate wound healing at the titanium mesh exposure site following cranioplasty. However, an individualized treatment strategy is required for each patient, and complications should be managed by adopting standard measures.


Assuntos
Procedimentos de Cirurgia Plástica , Crânio , Telas Cirúrgicas , Infecção da Ferida Cirúrgica , Titânio , Humanos , Pessoa de Meia-Idade , Masculino , Adulto , Feminino , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Idoso , Adolescente , Crânio/cirurgia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/cirurgia , Retalhos Cirúrgicos , Adulto Jovem , Cicatrização , Complicações Pós-Operatórias/cirurgia , Transplante de Pele
6.
Growth Horm IGF Res ; 76: 101594, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38833815

RESUMO

OBJECTIVES: This study aims to investigate whether the middle ear resonance frequency (RF) is affected in acromegaly, which causes growth in the skull bone. METHODS: Thirty acromegaly patients and 38 volunteers were included in the study. Pure tone average scores and middle ear RF values of the groups that underwent pure tone audiometry, tympanometry, and multifrequency tympanometry tests were compared. RESULTS: The pure tone mean was 14.95 ± 12.13 in acromegaly patients and 5.70 ± 8.52 in the control group (p:0.18). Sensorineural hearing loss(SNHL) was observed in 16.6% of the patients. The average middle ear RF was calculated as 815 ± 179.05 Hz in patients with acromegaly and 773 ± 127.15 in the control group. (p = 0.0001). CONCLUSION: This study is the first to evaluate middle-ear RF in acromegaly patients. Acromegaly-induced changes in soft tissues and bone structures impact middle ear functions. In this patient group, we found an increase in middle ear RF without conductive-type hearing loss and a 16.6% rate of SNHL.


Assuntos
Acromegalia , Orelha Média , Crânio , Humanos , Acromegalia/fisiopatologia , Acromegalia/patologia , Feminino , Orelha Média/patologia , Masculino , Adulto , Crânio/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos de Casos e Controles , Perda Auditiva Neurossensorial , Testes de Impedância Acústica , Audiometria de Tons Puros , Prognóstico
7.
Sci Rep ; 14(1): 13817, 2024 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879680

RESUMO

The nasal cavity of living mammals is a unique structural complex among tetrapods, acquired along a series of major morphological transformations that occurred mainly during the Mesozoic Era, within the Synapsida clade. Particularly, non-mammaliaform cynodonts document several morphological changes in the skull, during the Triassic Period, that represent the first steps of the mammalian bauplan. We here explore the nasal cavity of five cynodont taxa, namely Thrinaxodon, Chiniquodon, Prozostrodon, Riograndia, and Brasilodon, in order to discuss the main changes within this skull region. We did not identify ossified turbinals in the nasal cavity of these taxa and if present, as non-ossified structures, they would not necessarily be associated with temperature control or the development of endothermy. We do, however, notice a complexification of the cartilage anchoring structures that divide the nasal cavity and separate it from the brain region in these forerunners of mammals.


Assuntos
Fósseis , Mamíferos , Crânio , Conchas Nasais , Microtomografia por Raio-X , Animais , Mamíferos/anatomia & histologia , Fósseis/anatomia & histologia , Crânio/anatomia & histologia , Crânio/diagnóstico por imagem , América do Sul , Conchas Nasais/anatomia & histologia , Conchas Nasais/diagnóstico por imagem , Evolução Biológica , Cavidade Nasal/anatomia & histologia , Cavidade Nasal/diagnóstico por imagem , Filogenia
8.
PeerJ ; 12: e17544, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881866

RESUMO

Much of the ecological discourse surrounding the polarising theropod Spinosaurus has centred on qualitative discussions. Using a quantitative multivariate data analytical approach on size-adjusted linear measurements of the skull, we examine patterns in skull shape across a range of sauropsid clades and three ecological realms (terrestrial, semi-aquatic, and aquatic). We utilise cluster analyses to identify emergent properties of the data which associate properties of skull shape with ecological realm occupancy. Results revealed terrestrial ecologies to be significantly distinct from both semi- and fully aquatic ecologies, the latter two were not significantly different. Spinosaurids (including Spinosaurus) plotted away from theropods in morphospace and close to both marine taxa and wading birds. The position of nares and the degree of rostral elongation had the greatest effect on categorisation. Comparisons of supervised (k-means) and unsupervised clustering demonstrated categorising taxa into three groups (ecological realms) was inappropriate and suggested instead that cluster division is based on morphological adaptations to feeding on aquatic versus terrestrial food items. The relative position of the nares in longirostrine taxa is associated with which skull bones are elongated. Rostral elongation is observed by either elongating the maxilla and the premaxilla or by elongating the maxilla only. This results in the nares positioned towards the orbits or towards the anterior end of the rostrum respectively, with implications on available feeding methods. Spinosaurids, especially Spinosaurus, show elongation in the maxilla-premaxilla complex, achieving similar functional outcomes to elongation of the premaxilla seen in birds, particularly large-bodied piscivorous taxa. Such a skull construction would bolster "stand-and-wait" predation of aquatic prey to a greater extent than serving other proposed feeding methods.


Assuntos
Dinossauros , Ecossistema , Crânio , Animais , Crânio/anatomia & histologia , Dinossauros/anatomia & histologia , Dinossauros/fisiologia , Análise por Conglomerados , Fósseis
9.
PLoS Biol ; 22(6): e3002664, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829885

RESUMO

Neuroscientists studying the neural correlates of mouse behavior often lack access to the brain-wide activity patterns elicited during a specific task of interest. Fortunately, large-scale imaging is becoming increasingly accessible thanks to modalities such as Ca2+ imaging and functional ultrasound (fUS). However, these and other techniques often involve challenging cranial window procedures and are difficult to combine with other neuroscience tools. We address this need with an open-source 3D-printable cranial implant-the COMBO (ChrOnic Multimodal imaging and Behavioral Observation) window. The COMBO window enables chronic imaging of large portions of the brain in head-fixed mice while preserving orofacial movements. We validate the COMBO window stability using both brain-wide fUS and multisite two-photon imaging. Moreover, we demonstrate how the COMBO window facilitates the combination of optogenetics, fUS, and electrophysiology in the same animals to study the effects of circuit perturbations at both the brain-wide and single-neuron level. Overall, the COMBO window provides a versatile solution for performing multimodal brain recordings in head-fixed mice.


Assuntos
Encéfalo , Optogenética , Animais , Camundongos , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Optogenética/métodos , Neurônios/fisiologia , Camundongos Endogâmicos C57BL , Crânio/fisiologia , Masculino , Comportamento Animal/fisiologia , Imagem Multimodal/métodos , Ultrassonografia/métodos , Impressão Tridimensional
10.
Sci Data ; 11(1): 626, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871782

RESUMO

The chondrocranium provides the key initial support for the fetal brain, jaws and cranial sensory organs in all vertebrates. The patterns of shaping and growth of the chondrocranium set up species-specific development of the entire craniofacial complex. The 3D development of chondrocranium have been studied primarily in animal model organisms, such as mice or zebrafish. In comparison, very little is known about the full 3D human chondrocranium, except from drawings made by anatomists many decades ago. The knowledge of human-specific aspects of chondrocranial development are essential for understanding congenital craniofacial defects and human evolution. Here advanced microCT scanning was used that includes contrast enhancement to generate the first 3D atlas of the human fetal chondrocranium during the middle trimester (13 to 19 weeks). In addition, since cartilage and bone are both visible with the techniques used, the  endochondral ossification of cranial base was mapped since this region is so critical for brain and jaw growth. The human 3D models are published as a scientific resource for human development.


Assuntos
Imageamento Tridimensional , Humanos , Feto/diagnóstico por imagem , Feminino , Microtomografia por Raio-X , Crânio/diagnóstico por imagem , Crânio/embriologia , Gravidez , Cartilagem/diagnóstico por imagem , Cartilagem/embriologia
11.
Sci Rep ; 14(1): 13707, 2024 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877045

RESUMO

Determining the fundamental characteristics that define a face as "feminine" or "masculine" has long fascinated anatomists and plastic surgeons, particularly those involved in aesthetic and gender-affirming surgery. Previous studies in this area have relied on manual measurements, comparative anatomy, and heuristic landmark-based feature extraction. In this study, we collected retrospectively at Cedars Sinai Medical Center (CSMC) a dataset of 98 skull samples, which is the first dataset of this kind of 3D medical imaging. We then evaluated the accuracy of multiple deep learning neural network architectures on sex classification with this dataset. Specifically, we evaluated methods representing three different 3D data modeling approaches: Resnet3D, PointNet++, and MeshNet. Despite the limited number of imaging samples, our testing results show that all three approaches achieve AUC scores above 0.9 after convergence. PointNet++ exhibits the highest accuracy, while MeshNet has the lowest. Our findings suggest that accuracy is not solely dependent on the sparsity of data representation but also on the architecture design, with MeshNet's lower accuracy likely due to the lack of a hierarchical structure for progressive data abstraction. Furthermore, we studied a problem related to sex determination, which is the analysis of the various morphological features that affect sex classification. We proposed and developed a new method based on morphological gradients to visualize features that influence model decision making. The method based on morphological gradients is an alternative to the standard saliency map, and the new method provides better visualization of feature importance. Our study is the first to develop and evaluate deep learning models for analyzing 3D facial skull images to identify imaging feature differences between individuals assigned male or female at birth. These findings may be useful for planning and evaluating craniofacial surgery, particularly gender-affirming procedures, such as facial feminization surgery.


Assuntos
Aprendizado Profundo , Imageamento Tridimensional , Redes Neurais de Computação , Crânio , Humanos , Crânio/anatomia & histologia , Crânio/diagnóstico por imagem , Imageamento Tridimensional/métodos , Feminino , Masculino , Estudos Retrospectivos , Caracteres Sexuais , Adulto , Processamento de Imagem Assistida por Computador/métodos
12.
Niger J Clin Pract ; 27(5): 647-653, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38842715

RESUMO

BACKGROUND: The occipital spur (OS) can be described as an abnormal elongation of the external occipital protuberance (EOP). The cephalic index (CI) refers to the ratio of width to length in any skull. AIM: The aim of the present study was to evaluate the frequency and types of OS. It also aimed to determine the mean CI and the distribution of skull types using cone beam computed tomography (CBCT). And to determine if there was a relationship between the cephalic index and the presence and types of OS. METHODS: CBCT scans from 523 patients were included in the study. OSs were classified as type 1 (flat), type 2 (crest), and type 3 (spine). Skull length and width were measured on axial sections and the CI was calculated. Based on the cephalic index (CI), skull types were classified as dolichocephalic (CI < 75), mesocephalic (75 < CI < 80), brachycephalic (80 < CI < 85), and hyperbrachycephalic (CI > 85). RESULTS: The most common cranial types in the study group were brachycephalic (44.7%), mesocephalic (28.3%), hyperbrachycephalic (21.2%), and dolichocephalic (5.7%). Regarding the presence of OS, 54.3% of the participants had no OS, 23.1% had flat type, 15.3% had crest type, and 7.2% had spin type OS. There was a statistically significant difference (P < 0.05) in the frequency of OS according to skull type. CONCLUSION: This study, the first to evaluate CI and OS using CBCT, concludes that brachycephaly is the most common cranial type. OS is more common in mesocephalic and dolichocephalic skulls, at older ages, and in males.


Assuntos
Cefalometria , Tomografia Computadorizada de Feixe Cônico , Osso Occipital , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Masculino , Feminino , Osso Occipital/diagnóstico por imagem , Osso Occipital/anatomia & histologia , Adulto , Pessoa de Meia-Idade , Cefalometria/métodos , Adolescente , Adulto Jovem , Criança , Idoso , Pré-Escolar , Crânio/diagnóstico por imagem , Crânio/anatomia & histologia
13.
Fa Yi Xue Za Zhi ; 40(2): 128-134, 2024 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38847026

RESUMO

OBJECTIVES: To establish age estimation models of northern Chinese Han adults using cranial suture images obtained by CT and multiplanar reformation (MPR), and to explore the applicability of cranial suture closure rule in age estimation of northern Chinese Han population. METHODS: The head CT samples of 132 northern Chinese Han adults aged 29-80 years were retrospectively collected. Volume reconstruction (VR) and MPR were performed on the skull, and 160 cranial suture tomography images were generated for each sample. Then the MPR images of cranial sutures were scored according to the closure grading criteria, and the mean closure grades of sagittal suture, coronal sutures (both left and right) and lambdoid sutures (both left and right) were calculated respectively. Finally taking the above grades as independent variables, the linear regression model and four machine learning models for age estimation (gradient boosting regression, support vector regression, decision tree regression and Bayesian ridge regression) were established for northern Chinese Han adults age estimation. The accuracy of each model was evaluated. RESULTS: Each cranial suture closure grade was positively correlated with age and the correlation of sagittal suture was the highest. All four machine learning models had higher age estimation accuracy than linear regression model. The support vector regression model had the highest accuracy among the machine learning models with a mean absolute error of 9.542 years. CONCLUSIONS: The combination of skull CT-MPR and machine learning model can be used for age estimation in northern Chinese Han adults, but it is still necessary to combine with other adult age estimation indicators in forensic practice.


Assuntos
Determinação da Idade pelo Esqueleto , Povo Asiático , Suturas Cranianas , Aprendizado de Máquina , Tomografia Computadorizada por Raios X , Humanos , Suturas Cranianas/diagnóstico por imagem , Pessoa de Meia-Idade , Adulto , Idoso , Idoso de 80 Anos ou mais , Determinação da Idade pelo Esqueleto/métodos , Estudos Retrospectivos , Feminino , China/etnologia , Masculino , Crânio/diagnóstico por imagem , Antropologia Forense/métodos , Teorema de Bayes , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional , Etnicidade , Modelos Lineares , População do Leste Asiático
14.
J Morphol ; 285(6): e21740, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38858850

RESUMO

The neurocranial elevation generated by axial muscles is widespread among aquatic gnathostomes. The mechanism has two functions: first, it contributes to the orientation of the mouth gape, and second, it is involved in suction feeding. To provide such mobility, anatomical specialization of the anterior part of the vertebral column has evolved in many fish species. In modern chimaeras, the anterior part of the vertebral column develops into the synarcual. Possible biological roles of the occipital-synarcual joint have not been discussed before. Dissections of the head of two species of ratfishes (Chimaera monstrosa and Chimaera phantasma) confirmed the heterocoely of the articulation surface between the synarcual and the neurocranium, indicating the possibility of movements in the sagittal and frontal planes. Muscles capable of controlling the movements of the neurocranium were described. The m. epaxialis is capable of elevating the head, the m. coracomandibularis is capable of lowering it if the mandible is anchored by the adductor. Lateral flexion is performed by the m. lateroventralis, for which this function was proposed for the first time. The first description of the m. epaxialis profundus is given, its function is to be elucidated in the future. Manipulations with joint preparations revealed a pronounced amplitude of movement in the sagittal and frontal planes. Since chimaeras generate weak decrease in pressure in the oropharyngeal cavity when sucking in prey, we hypothesised the primary effect of neurocranial elevation, in addition to the evident lateral head mobility, is accurate prey targeting.


Assuntos
Peixes , Animais , Peixes/fisiologia , Peixes/anatomia & histologia , Crânio/anatomia & histologia , Crânio/fisiologia , Adaptação Fisiológica , Articulações/fisiologia , Articulações/anatomia & histologia
15.
Sultan Qaboos Univ Med J ; 24(2): 250-258, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38828246

RESUMO

Objectives: Cranioplasty is a complex craniofacial and neurosurgical procedure that aims to reinstate the architecture of the cranial vault and elevate both its aesthetic and neurological function. Several reconstructive materials have been thoroughly explored in the search for the optimal solution for cranioplasty. This study aimed to evaluate different material used for cranial reconstruction in Oman. Methods: This retrospective study included all patients who had had cranioplasty procedures performed at Khoula Hospital, Muscat, Oman, from 2012 to 2022. Demographic information, the characteristics of the cranial defect and any complications that occurred post-operatively were analysed. Results: A total of 47 patients were included in this study. The most common cause of cranial defects was craniectomy following traumatic head injury (70.2%) along with excision of fibrous dysplasia (10.6%). The most frequently utilised material for cranial repair was autologous bone grafts (n = 28), followed by polyetheretherketone (PEEK; n = 14). Interestingly, the replacement of bone grafts from previous craniectomy showed a notably high resorption rate (71.4%), in contrast to split calvarial grafts (0%) and other types of bone grafts (14.3%). Additionally, delayed graft infection was observed in 3.6% of the bone graft group and 7.1% of the PEEK group. Conclusion: Patient-specific alloplastic implants such as PEEK have gained popularity for large and complex cranioplasty, as they provide excellent aesthetic outcomes and leave no donor site morbidity. In contrast, bone grafts remain the gold standard for small to medium-sized cranial defects.


Assuntos
Procedimentos de Cirurgia Plástica , Humanos , Omã/epidemiologia , Estudos Retrospectivos , Masculino , Feminino , Adulto , Procedimentos de Cirurgia Plástica/métodos , Procedimentos de Cirurgia Plástica/estatística & dados numéricos , Pessoa de Meia-Idade , Adolescente , Crânio/cirurgia , Criança , Transplante Ósseo/métodos , Transplante Ósseo/estatística & dados numéricos , Polímeros/uso terapêutico , Benzofenonas , Idoso , Pré-Escolar
16.
Sci Transl Med ; 16(749): eadj3143, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809965

RESUMO

Visualization of human brain activity is crucial for understanding normal and aberrant brain function. Currently available neural activity recording methods are highly invasive, have low sensitivity, and cannot be conducted outside of an operating room. Functional ultrasound imaging (fUSI) is an emerging technique that offers sensitive, large-scale, high-resolution neural imaging; however, fUSI cannot be performed through the adult human skull. Here, we used a polymeric skull replacement material to create an acoustic window compatible with fUSI to monitor adult human brain activity in a single individual. Using an in vitro cerebrovascular phantom to mimic brain vasculature and an in vivo rodent cranial defect model, first, we evaluated the fUSI signal intensity and signal-to-noise ratio through polymethyl methacrylate (PMMA) cranial implants of different thicknesses or a titanium mesh implant. We found that rat brain neural activity could be recorded with high sensitivity through a PMMA implant using a dedicated fUSI pulse sequence. We then designed a custom ultrasound-transparent cranial window implant for an adult patient undergoing reconstructive skull surgery after traumatic brain injury. We showed that fUSI could record brain activity in an awake human outside of the operating room. In a video game "connect the dots" task, we demonstrated mapping and decoding of task-modulated cortical activity in this individual. In a guitar-strumming task, we mapped additional task-specific cortical responses. Our proof-of-principle study shows that fUSI can be used as a high-resolution (200 µm) functional imaging modality for measuring adult human brain activity through an acoustically transparent cranial window.


Assuntos
Encéfalo , Crânio , Humanos , Encéfalo/diagnóstico por imagem , Animais , Crânio/diagnóstico por imagem , Ultrassonografia/métodos , Ratos , Acústica , Imagens de Fantasmas , Polimetil Metacrilato/química , Razão Sinal-Ruído , Masculino
17.
Plast Reconstr Surg ; 153(6): 1379-1386, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810163

RESUMO

BACKGROUND: Patients are commonly monitored for hyponatremia after intracranial procedures, yet the prevalence of hyponatremia after cranial vault reconstruction (CVR) remains unclear. The purpose of this study is to define the prevalence, risk factors, and complications of hyponatremia after CVR to optimize postoperative sodium surveillance protocols. METHODS: Patients with nonsyndromic, single-suture craniosynostosis who underwent primary CVR between 2009 and 2020 at Michigan Medicine were included (n = 231). Demographic, intraoperative, and postoperative characteristics were compared by postoperative hyponatremia status at P < 0.05 significance. Hyponatremia was defined as mild (<135 mEq/L), moderate (<130 mEq/L), or severe (<125 mEq/L) based on the lowest postoperative laboratory draw. RESULTS: Twenty-three patients (10.0%) developed mild postoperative hyponatremia. No patient developed moderate or severe postoperative hyponatremia. On multivariable regression, decreased preoperative sodium level (P = 0.03) and decreased preoperative weight (P = 0.02) were significantly associated with mild postoperative hyponatremia. No patient developed complications or required hospital readmission because of hyponatremia. CONCLUSIONS: This large retrospective cohort study of patients with nonsyndromic single-suture craniosynostosis demonstrated a 10% prevalence of mild, clinically inconsequential hyponatremia and 0% prevalence of moderate or severe, clinically significant hyponatremia after primary CVR. Patients with low preoperative sodium level or weight were at increased risk for developing mild postoperative hyponatremia. The results suggest that patients with preoperative sodium greater than 140 mEq/L or preoperative weight greater than 10 kg may be candidates for limited postoperative sodium surveillance; however, future prospective studies are warranted before implementation. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.


Assuntos
Craniossinostoses , Hiponatremia , Procedimentos de Cirurgia Plástica , Complicações Pós-Operatórias , Humanos , Hiponatremia/epidemiologia , Hiponatremia/etiologia , Craniossinostoses/cirurgia , Feminino , Masculino , Estudos Retrospectivos , Prevalência , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Procedimentos de Cirurgia Plástica/efeitos adversos , Procedimentos de Cirurgia Plástica/métodos , Lactente , Fatores de Risco , Michigan/epidemiologia , Crânio/cirurgia
18.
Neurol India ; 72(2): 391-394, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38817177

RESUMO

Role of 3-D models in the identification of the site and extent of bone defects in the skull base for the treatment of CSF rhinorrhea is analyzed. Such models were used successfully in the management of two patients who failed previous attempts at basal reconstruction. The principal advantage of the models was in exact delineation of the size and site of bone defect and deciphering of its relationship with adjoining critical regions of the brain.


Assuntos
Rinorreia de Líquido Cefalorraquidiano , Impressão Tridimensional , Humanos , Crânio/diagnóstico por imagem , Masculino , Adulto , Base do Crânio/diagnóstico por imagem , Base do Crânio/patologia , Modelos Anatômicos , Feminino , Imageamento Tridimensional , Tomografia Computadorizada por Raios X
19.
Nature ; 629(8013): 810-818, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38778234

RESUMO

Accurate and continuous monitoring of cerebral blood flow is valuable for clinical neurocritical care and fundamental neurovascular research. Transcranial Doppler (TCD) ultrasonography is a widely used non-invasive method for evaluating cerebral blood flow1, but the conventional rigid design severely limits the measurement accuracy of the complex three-dimensional (3D) vascular networks and the practicality for prolonged recording2. Here we report a conformal ultrasound patch for hands-free volumetric imaging and continuous monitoring of cerebral blood flow. The 2 MHz ultrasound waves reduce the attenuation and phase aberration caused by the skull, and the copper mesh shielding layer provides conformal contact to the skin while improving the signal-to-noise ratio by 5 dB. Ultrafast ultrasound imaging based on diverging waves can accurately render the circle of Willis in 3D and minimize human errors during examinations. Focused ultrasound waves allow the recording of blood flow spectra at selected locations continuously. The high accuracy of the conformal ultrasound patch was confirmed in comparison with a conventional TCD probe on 36 participants, showing a mean difference and standard deviation of difference as -1.51 ± 4.34 cm s-1, -0.84 ± 3.06 cm s-1 and -0.50 ± 2.55 cm s-1 for peak systolic velocity, mean flow velocity, and end diastolic velocity, respectively. The measurement success rate was 70.6%, compared with 75.3% for a conventional TCD probe. Furthermore, we demonstrate continuous blood flow spectra during different interventions and identify cascades of intracranial B waves during drowsiness within 4 h of recording.


Assuntos
Velocidade do Fluxo Sanguíneo , Encéfalo , Circulação Cerebrovascular , Ultrassonografia , Humanos , Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Circulação Cerebrovascular/fisiologia , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Erros Médicos , Razão Sinal-Ruído , Pele , Crânio , Sonolência/fisiologia , Ultrassonografia/instrumentação , Ultrassonografia/métodos , Adulto
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