Back to the Roots: Reconstructing Large and Complex Cranial Defects using an Image-based Statistical Shape Model.

Designing implants for large and complex cranial defects is a challenging task, even for professional designers. Current efforts on automating the design process focused mainly on convolutional neural networks (CNN), which have produced state-of-the-art results on reconstructing synthetic defects. However, existing CNN-based methods have been difficult to translate to clinical practice in cranioplasty, as their performance on large and complex cranial defects remains unsatisfactory. In this paper, we present a statistical shape model (SSM) built directly on the segmentation masks of the skulls represented as binary voxel occupancy grids and evaluate it on several cranial implant design datasets. Results show that, while CNN-based approaches outperform the SSM on synthetic defects, they are inferior to SSM when it comes to large, complex and real-world defects. Experienced neurosurgeons evaluate the implants generated by the SSM to be feasible for clinical use after minor manual corrections. Datasets and the SSM model are publicly available at https://github.com/Jianningli/ssm .

Biological Identification of Skulls in Indonesian and Thai Populations: Ancestry Estimation, Sex Determination, Stature Estimation, and Age Estimation / Identificación Biológica de Cráneos en Poblaciones de Indonesia y Tailandia: Estimación de Ascendencia, Determinación del Sexo, Estimación de Estatura y Estimación de Edad

SUMMARY: This review article will present an overview of biological profiles in forensic utilities. The biological profile of the skull in the existing literature can help to identify humans, especially if the condition of the victim found is a result of mutilation or a bomb explosion. When it comes to the precision of identifying skeletal remains, the human skull is frequently cited as being first in the estimation of age and ancestry and second in terms of sex and stature. It can be an alternative to assessing the following biological parameters: sex, age, stature, and ancestry. The implementation of biological profiles in the identification process is very important considering that some cases require the assistance of forensic anthropology. This review article shows the importance of the value of skulls. The method that can be applied is craniometry which can be used to determine sex, age, stature, and estimated ancestry. Different results will occur depending on the completeness of the skull. Therefore, estimation formulas have different accurate results. Discriminant function analysis has been performed on various measurement sets and its discriminant power has been validated by many researchers. Geometric morphometric analysis has become the main tool for shape analysis and many attempts have been made to use it in analyzing skulls. Several methods supported by technology have also been developed. It is hoped that the review article will show significant differences in results between studies in Thailand and Indonesia, even though they are in the same racial group.

Este artículo presenta una descripción general de los perfiles biológicos en las utilidades forenses. El perfil biológico del cráneo en la literatura existente puede ayudar a identificar a los humanos, especialmente si la condición en la que se encuentra la víctima es el resultado de una mutilación o la explosión de una bomba. Cuando se trata de la precisión en la identificación de restos óseos, el cráneo humano se cita con frecuencia como el primero en la estimación de edad y ascendencia y el segundo en términos de sexo y estatura. Puede ser una alternativa para evaluar los siguientes parámetros biológicos: sexo, edad, estatura y ascendencia. La implementación de perfiles biológicos en el proceso de identificación es importante considerando que algunos casos requieren la asistencia de la antropología forense. Este artículo de revisión muestra la importancia del valor de las cnezas óseas. El método que se puede aplicar es la craneometría para determinar el sexo, la edad, la estatura y la ascendencia estimada. Se pueden obtener diferentes resultados dependiendo de la integridad del cráneo. Por lo tanto, las fórmulas de estimación tienen resultados precisos diferentes. Se ha realizado un análisis de función discriminante en varios conjuntos de medidas y muchos investigadores han validado su poder discriminante. El análisis a través de la morfometría geométrica se ha convertido en la principal herramienta para el análisis de formas y se ha utilizado frecuentemente en el análisis de cráneos. También se han desarrollado varios métodos apoyados en la tecnología. Se espera que este trabajo muestre diferencias significativas en los resultados entre los estudios realizados en Tailandia e Indonesia, aunque pertenezcan al mismo grupo racial.

Wormian Bones: Prevalence, Topography, and Implications.

BACKGROUND: Wormian bones also known as sutural bones are asymmetrical and shapeless bones occurring in cranial sutures and fontanelle of the skull. Their incidence is reported to vary in population. The exact etiology is debatable, but their formation is under the control of both genetic and environmental factors and has great anthropological and clinical implications related to the cranium. Due to high clinical relevance of Wormian bones, the study was carried out. The aim of the study is to expound the incidence and topography of Wormian bones along with clinical significance in dry adult skulls of Indian origin. METHODS: The study was conducted in the Department of Anatomy using 200 complete adult dry skulls of unknown age and sex. All the sutures in the skull were inspected for the presence of Wormian bones. The Wormian bones were classified into 10 categories, and associated implications were brought out. The Wormian bones were photographed, and details were compared with the available literature. RESULTS: The Wormian bones were observed in 190 (380 sides) skulls with 186 on the right side and 108 on the left side. The predominance site of sutural bone was lambdoid suture followed by sagittal suture. The least common site of Wormian bone was lambda. CONCLUSION: The detailed information of precise topography, frequency, and number of Wormian bones is of utmost use for surgeons performing surgery on the skull, anthropologists for identifying races, and forensic scientists for investigating child abuse cases.

A Deep Learning Framework for Skull Stripping in Brain MRI.

Skull-stripping, an important pre-processing step in neuroimage computing, involves the automated removal of non-brain anatomy (such as the skull, eyes, and ears) from brain images to facilitate brain segmentation and analysis. Manual segmentation is still practiced, but it is time-consuming and highly dependent on the expertise of clinicians or image analysts. Prior studies have developed various skull-stripping algorithms that perform well on brains with mild or no structural abnormalities. Nonetheless, they were not able to address the issue for brains with significant morphological changes, such as those caused by brain tumors, particularly when the tumors are located near the skull's border. In such cases, a portion of the normal brain may be stripped, or the reverse may occur during skull stripping. To address this limitation, we propose to use a novel deep learning framework based on nnUNet for skull stripping in brain MRI. Two publicly available datasets were used to evaluate the proposed method, including a normal brain MRI dataset - The Neurofeedback Skull-stripped Repository (NFBS), and a brain tumor MRI dataset - The Cancer Genome Atlas (TCGA). The method proposed in the study performed better than six other current methods, namely BSE, ROBEX, UNet, SC-UNet, MV-UNet, and 3D U-Net. The proposed method achieved an average Dice coefficient of 0.9960, a sensitivity of 0.9999, and a specificity of 0.9996 on the NFBS dataset, and an average Dice coefficient of 0.9296, a sensitivity of 0.9288, a specificity of 0.9866 and an accuracy of 0.9762 on the TCGA brain tumor dataset.

Analysis of the Asterion Morphology in Relation to Its Clinical Significance / Análisis de la Morfología del Asterion en Relación con su Importancia Clínica

SUMMARY: The asterion presents a significant anthropological marking and meeting point between three sutures. It is a surface landmark for the transverse-sigmoid venous sinus complex and is also a surgical landmark for access to the posterior cranial fossa, giving it clinical importance. The aim of this research was to analyze the shape of the asterion and to set the measurement methods that will determine distance between the asterion and surrounding features. The study sample, as a part of the Osteological collection of the Department of Anatomy, Faculty of Medicine Novi Sad, consisted of 43 skulls. Morphometric analysis was related to the measurement of the defined parameters and descriptive analysis presented the classification of asterion in relation to the presence of sutural bones, as well as the determination of the position of the asterion according to the transverse-sigmoid venous complex. There was a statistically significant difference between male and female skulls for all the measured parameters. The results show that 34.88 % were type 1 (one or more sutural bones are present) and 65.12 % were type 2 asteria (no sutural bones are present). More frequent occurrence of asteria type 2 was seen on both, male and female skulls. The most frequent position of the asteria on both sides of the skull was in the transverse- sigmoid venous complex (76.92 % on the right side vs. 72.22 % on the left cranial side). Clinical significance of knowing the area of asterion is reflected in order to make the surgical, as well as diagnostic procedures, as successful as possible.

El asterion presenta una importante marca antropológica y punto de encuentro entre tres suturas. Es un punto de referencia de superficie para el complejo del seno venoso sigmoideo transverso y también es un punto de referencia quirúrgico para el acceso a la fosa craneal posterior, lo que le confiere importancia clínica. El objetivo de esta investigación fue analizar la forma del asterión y establecer los métodos de medición que determinarán la distancia entre el asterión y las características circundantes. La muestra del estudio, que forma parte de la colección osteológica del Departamento de Anatomía de la Facultad de Medicina de Novi Sad, estuvo compuesta por 43 cráneos. El análisis morfométrico se relacionó con la medición de los parámetros definidos y el análisis descriptivo presentó la clasificación del asterion en relación a la presencia de huesos suturales, así como la determinación de la posición del asterion según el complejo venoso transverso-sigmoideo. Hubo una diferencia estadísticamente significativa entre los cráneos masculinos y femeninos para todos los parámetros medidos. Los resultados muestran que el 34,88 % eran tipo 1 (hay uno o más huesos suturales presentes) y el 65,12 % eran asteria tipo 2 (no hay huesos suturales presentes). Se observó una aparición más frecuente de asteria tipo 2 en cráneos tanto masculinos como femeninos. La posición más frecuente de la asteria en ambos lados del cráneo fue en el complejo venoso sigmoideo transverso (76,92 % en el lado derecho vs. 72,22 % en el lado craneal izquierdo). La importancia clínica de conocer el área de asterion se refleja en que los procedimientos quirúrgicos y de diagnóstico tengan el mejor resultado posible.

Pediatric focal calvarial lesions: an illustrated review.

Focal skull lesions in children can be diagnostically challenging with a wide variety of potential etiologies. Understanding the diverse pathologies and recognizing their associated clinical and imaging characteristics is crucial for accurate diagnosis and appropriate treatment planning. We review pertinent anatomy of the scalp and calvarium and review different pathologies that can present with focal skull lesions in pediatric patients. These include neoplastic, non-neoplastic tumor-like, congenital, post traumatic, and vascular-associated etiologies. We review the key clinical and imaging features associated with these pathologies and present teaching points to help make the correct diagnosis. It is important for radiologists to be aware of the common and rare etiologies of skull lesions as well as the clinical and imaging characteristics which can be used to develop an accurate differential to ensure a timely diagnosis and initiate appropriate management.

Turtle skull development unveils a molecular basis for amniote cranial diversity.

Amniote skulls display diverse architectural patterns including remarkable variations in the number of temporal arches surrounding the upper and lower temporal fenestrae. However, the cellular and molecular basis underlying this diversification remains elusive. Turtles are a useful model to understand skull diversity due to the presence of secondarily closed temporal fenestrae and different extents of temporal emarginations (marginal reduction of dermal bones). Here, we analyzed embryos of three turtle species with varying degrees of temporal emargination and identified shared widespread coexpression of upstream osteogenic genes Msx2 and Runx2 and species-specific expression of more downstream osteogenic genes Sp7 and Sparc in the head. Further analysis of representative amniote embryos revealed differential expression patterns of osteogenic genes in the temporal region, suggesting that the spatiotemporal regulation of Msx2, Runx2, and Sp7 distinguishes the temporal skull morphology among amniotes. Moreover, the presence of Msx2- and/or Runx2-positive temporal mesenchyme with osteogenic potential may have contributed to their extremely diverse cranial morphology in reptiles.

Evaluation of 3D Printed Burr Hole Simulation Models Using 8 Different Materials.

OBJECTIVE: 3D printing is increasingly used to fabricate three-dimensional neurosurgical simulation models, making training more accessible and economical. 3D printing includes various technologies with different capabilities for reproducing human anatomy. This study evaluated different materials across a broad range of 3D printing technologies to identify the combination that most precisely represents the parietal region of the skull for burr hole simulation. METHODS: Eight different materials (polyethylene terephthalate glycol, Tough PLA, FibreTuff, White Resin, BoneSTN, SkullSTN, polymide [PA12], glass-filled polyamide [PA12-GF]) across 4 different 3D printing processes (fused filament fabrication, stereolithography, material jetting, selective laser sintering) were produced as skull samples that fit into a larger head model derived from computed tomography imaging. Five neurosurgeons conducted burr holes on each sample while blinded to the details of manufacturing method and cost. Qualities of mechanical drilling, visual appearance, skull exterior, and skull interior (i.e., diploë) and overall opinion were documented, and a final ranking activity was performed along with a semistructured interview. RESULTS: The study found that 3D printed polyethylene terephthalate glycol (using fused filament fabrication) and White Resin (using stereolithography) were the best models to replicate the skull, surpassing advanced multimaterial samples from a Stratasys J750 Digital Anatomy Printer. The interior (e.g., infill) and exterior structures strongly influenced the overall ranking of samples. All neurosurgeons agreed that practical simulation with 3D printed models can play a vital role in neurosurgical training. CONCLUSIONS: The study findings reveal that widely accessible desktop 3D printers and materials can play a valuable role in neurosurgical training.

Osteological Study of the Parietal Foramen in the Adult Human Skull Bones and its Clinical and Surgical Correlations / Estudio Osteológico del Foramen Parietal en los Huesos del Cráneo Humano Adulto y sus Correlaciones Clínicas y Quirúrgicas

SUMMARY: Parietal emissary foramina (PEF) are small holes, which are localized between the middle and posterior thirds of the parietal bone posterior surface close to the sagittal suture. PEF are important structures that protect the parietal emissary vein, which passes through it. During neurosurgery procedures, parietal foramina (PF) knowledge is crucial. This work aimed to evaluate presence and location of the PF in the skull of an adult human. Moreover, measure the distance amidst PF and the sagittal suture's midline to ascertain its clinical repercussions. 74 adult human skulls, without gross pathology, were observed for the PF's existence. The PF's and sagittal suture's midline distance were measured. According to the PF patterns of presence, five groups were distributed. Finally, specimens were photographed and subjected to statistical analysis. The PF was absent in 7 skulls (9.5 %). There were 9 skulls (12.2 %) exhibited central parietal foramen where the parietal foramen lies on the sagittal suture. 17 skulls (23 %) showed right unilateral parietal foramen, whereas 15 skulls (20.3 %) demonstrated left unilateral parietal foramen. The final 26 skulls (35.1 %) exhibited bilateral parietal foramen. This descriptive study supplies valuable information of PF variations, which is crucial for neurosurgeons in modifying surgical techniques and procedures to alleviate injury to PF-emerging structures such as emissary veins.

Los forámenes emisarios parietales (FEP) son pequeños orificios que se localizan entre los tercios medio y posterior de la superficie posterior del hueso parietal, cerca de la sutura sagital. Los FEP son estructuras importantes que protegen la vena emisaria parietal, que lo atraviesa. Durante los procedimientos de neurocirugía, el conocimiento de los forámenes parietales (FP) es crucial. Este trabajo tuvo como objetivo evaluar la presencia y ubicación del FP en el cráneo de hombres adultos, además, medir la distancia entre el FP y la línea mediana de la sutura sagital para conocer su repercusión clínica. Se examinaron 74 cráneos humanos adultos, sin patología grave, para determinar la existencia del FP. Se midió la distancia de la línea mediana de la sutura sagital y del FP. De acuerdo con los patrones de presencia del FP, se distribuyeron en cinco grupos. Finalmente, los especímenes fueron fotografiados y sometidos a análisis estadístico. El PF estaba ausente en 7 cráneos (9,5 %). Hubo 9 cráneos (12,2 %) que presentaban un PF central localizándose en la sutura sagital. 17 cráneos (23 %) presentaban un FP unilateral derecho, mientras que 15 cráneos (20,3 %) se observó un FP unilateral izquierdo. Los 26 cráneos restantes (35,1 %) exhibieron FP bilaterales. Este estudio descriptivo proporciona información valiosa sobre las variaciones del FP, que es fundamental para los neurocirujanos en el momento de modificar las técnicas y los procedimientos quirúrgicos para aliviar las lesiones de las estructuras emergentes del FP, como las venas emisarias.

The Discovery of a Bone in the Anterior Fontanelle of the Skull of the Sheep (Ovis aries) / Descubrimiento de un Hueso en la Fontanela Anterior del Cráneo de la Oveja (Ovis aries)

SUMMARY: A comparative study of the skull morphology was conducted using 270 prenatal and 750 postnatal skull samples from three breeds of sheep in Nigeria namely, Balami, Uda and Yankasa. A unique bone peculiar to the Yankasa breeds of sheep was found consistently at the centre of the anterior fontanelle in the young (day-old to 1 year). At two years of age and above, the bone was fused and disappeared completely. This brings the total numbers of the neurocranium bones of the skull in the Yankasa breeds to 8, as against the 7 bones documented in the ovine species. Due to the fact that this bone has not been described in the literature, we venture to name it the anterio-fontanelle bone (of Atabo).

Se realizó un estudio comparativo de la morfología del cráneo utilizando 270 muestras de cráneos prenatales y 750 postnatales de tres razas de ovejas en Nigeria, Balami, Uda y Yankasa. Un hueso único peculiar de las razas de ovejas Yankasa se encontró consistentemente en el centro de la fontanela anterior en las crías (de un día a 1 año). A los dos años de edad o más, el hueso se fusionó y desapareció por completo. Esto eleva el número total de huesos del neurocráneo en el cráneo en las razas Yankasa a 8, frente a los 7 huesos documentados en la especie ovina. Debido a que este hueso no ha sido descrito en la literatura, nos aventuramos a denominarlo hueso antero-fontanela (de Atabo).

Pesquisa de novos pontos craniométricos para aumento da precisão em reconstrução facial forense / Ressearch of new craniometric points for more accurate facial reconstruction

A estimativa de aparência da face de uma pessoa, partindo de um crânio seco, é chamada de Reconstrução Facial Forense (RFF). Pode ser realizada de maneira digital ou manual, a partir da marcação de pontos cranianos, que possuem diferentes médias de espessura de tecido mole sobreposto. Nas reconstruções digitais o uso de tomografias computadorizadas de feixe cônico (TCFC), que nos permite obter o volume de pacientes sentados, possibilitou um avanço significativo na mensuração das médias de volume dos tecidos moles faciais. Foi desenvolvido um protocolo para medições de tecidos moles a partir de 32 pontos craniométricos (10 sagitais e 11 bilaterais). Este trabalho propõe a inserção de cinco novos pontos cranianos ao protocolo, com medidas a partir dos pontos Mentual (Ml), Supra Canino (sC), Fronto-zigomático (Fz), Ptério (Pt) e Posterior do Ramo Mandibular (prM), com o intuito de aumentar a acurácia das reconstruções. As TCFC foram manipuladas no software Horus® (LGPL 3.0) e mensuradas conforme protocolo adaptado de Beaini et al. (1), obtidas as espessuras de tecido mole a partir dos pontos craniométricos propostos. Foram estudadas 100 TCFC de brasileiros adultos (maiores de 18 anos) que disponibilizaram seus exames para utilização em pesquisas de maneira anônima e que compõe um banco de dados já estruturado e utilizado em pesquisas anteriores. Esse banco de dados contém exames de 50 indivíduos do sexo feminino e 50 do sexo masculino, separados em grupos por sexo e idade. Estatisticamente, foram aplicados testes de normalidade e a diferença entre cada grupo foi testada para obtenção das espessuras médias referentes a cada ponto craniano. Para o ponto Fz, as médias de espessura de tecidos moles foram de 4.56mm para mulheres e 5.14mm para homens. Para o ponto Ml, as médias de ETMF foram de 12.88mm para mulheres e 14.74mm para homens. No ponto prM, as médias de ETMF foram de 18.30mm para homens e 19.69mm para mulheres. No ponto Pt, as médias de ETMF foram de 11.01mm para mulheres e 13.09mm para homens. No ponto sC, as médias de ETMF foram de 10.99mm para mulheres e 12.71mm para homens. A divisão de ETMFs por sexo é justificada, concordando com parcela significativa da literatura, uma vez que quatro 10 dos cinco pontos estudados apresentaram diferenças estatísticas significativas, com as espessuras de indivíduos do sexo masculino sendo maiores que de indivíduos do sexo feminino.

Evaluation of the normal craniocervical junction craniometry in 137 asymptomatic patients / Evaluación de la craneometría de la unión craneocervical normal en 137 pacientes asintomáticos

SUMMARY: To our best knowledge, most of the craniometric studies on the normal craniocervical junction (CCJ), are still poorly studied and based on measurements taken from plain radiographs. In this study, the authors conducted a craniometric evaluation of the CCJ in a population without known CCJ abnormalities. The purpose of the study was to assess the normal CCJ craniometry based on measures obtained from CT scans. The authors examined 137 consecutive CCJ CT scans obtained in patients evaluated at their hospital for treatment of non-CCJ conditions between 2018 and 2019. Twelve craniometrical dimensions were conducted, including the relation of the odontoid with the cranial base, the atlantodental interval (ADI), the clivus length, and the clivus-canal angle (CCA).

Hasta donde sabemos, aun son escasos y pocos los estudios craneométricos respecto a la unión craneocervical normal (UCCN) y estos se basan en mediciones tomadas de radiografías simples. En este estudio, realizamos una evaluación craneométrica de la UCCN en una población sin anomalías conocidas. El propósito del estudio fue evaluar la craneometría UCCN normal en función de las medidas obtenidas de las tomografías computarizadas. Los autores examinaron 137 tomografías computarizadas UCCN consecutivas obtenidas en pacientes evaluados en su hospital para el tratamiento de condiciones no UCCN entre los años 2018 y 2019. Se realizaron doce dimensiones craneométricas, incluida la relación del proceso odontoides con la base del cráneo, el intervalo atlantodental (ADI), la longitud del clivus y el ángulo clivus-canal (CCA).

Clinical applications of the mastoid emissary vein.

PURPOSE: During retrosigmoid craniotomy, the mastoid emissary vein (MEV) can be a source of considerable bleeding during the operation, especially when the larger diameter MEV or sigmoid sinus is torn. In this study, we evaluated the relevant structure of the MEV for their anatomy and applied the data in surgery to summarize their clinical significance. METHODS: The posterior craniocervical regions of 15 silicon-injected Chinese human cadaver specimens were dissected to expose the MEV and adjacent structures. Fifty-one patients who were scheduled to undergo retrosigmoid craniotomy were selected. All patients underwent preoperative routine CT of the head. The relevant data were collected on cadaveric anatomy and CT. Eventually, all patients underwent retrosigmoid craniotomy and the MEV was observed during the operation. RESULTS: In cadaver specimens, the prevalence of the MEV was 90.0%. It originated from the middle and lower parts of the posterior wall of the sigmoid sinus and extended in the posterior direction in the mastoid process, usually having 1-2 external openings (86.7%) and only 1 internal opening. The intraosseous courses of the MEV were classified as straight and curved. The straight type accounted for 57.9%, and the curved type for 42.1%. The mean diameter of the MEV was 1.84 ± 0.85 mm, and the straight length of the MEV inside the mastoid process was 11.93 ± 3.58 mm. In 16.7% and 6.7% of all cadaver specimens, the MEV diameter was greater than 2.5 and 4 mm, respectively. In 51 patients (bilateral), routine head CT scan showed the MEV in 49.0% of the patients, and the MEV diameter was greater than 2.5 and 4 mm, respectively, in 17.6% (18/102) and 3.9% (4/102) of the cases. During surgery (unilateral) in the 51 patients, 48 had the MEV and 3 had no MEV. None of the patients had sigmoid sinus tears or massive bleeding. CONCLUSION: In the process of retrosigmoid craniotomy, detailed anatomical knowledge of the MEV, well-planned CT scan, and meticulous microsurgical techniques are key for successful operation, which can reduce the occurrence of complications.

Radiologic Evaluation of the Fossa Navicularis on Dry Skull: A Comparative CBCT Study.

Fossa navicularis (FN) is defined as bony depression that is not always present and is located anterior to the foramen magnum and pharyngeal tubercle on the inferior aspect of the basilar part of the occipital bone. It has been reported that FN can create an infection spread path from the pharynx to the intracranial structures. Therefore, the diagnosis of this variation is important. Although cone beam computed tomography (CBCT) diagnostic accuracy has mostly been verified in detection and quantification particularly on human skulls, there is no study comparing morphometric measurements between direct measurement on the skull and CBCT measurement. The main object of this study is to evaluate the presence of FN on dry bones and CBCT images of the same dry skull and to examine the morphometric and morphological features of this formation. Thirty-two random craniums that were made available for this study that did not have any fractures or deformities of the cranial base were examined. The sagittal diameter, transverse diameter, and depth of the FN was measured both directly on dry skulls and radiologically on CBCT images of dry skull. In addition, the shape of FN (SFN) was determined. FN was detected in 10 (31.25%) of 32 craniums examined with both modalities. It was determined that sagittal diameter of the FN, transverse diameter of the FN, depth of the FN, and the shape of FN did not show a statistically significant difference between the 2 measurements. Unlike the literature, FN was investigated on dry bones both directly and in CBCT images in this study. In contrast to previously thought the FN may be smaller according to this findings, and this small variation can be detected with CBCT images. According to this findings, it can be said that morphometric evaluations on CBCT are accurate and reliable, and CBCT is a safe method for clinical diagnosis and treatment.

Creating morphological diversity in reptilian temporal skull region: A review of potential developmental mechanisms.

Reptilian skull morphology is highly diverse and broadly categorized into three categories based on the number and position of the temporal fenestrations: anapsid, synapsid, and diapsid. According to recent phylogenetic analysis, temporal fenestrations evolved twice independently in amniotes, once in Synapsida and once in Diapsida. Although functional aspects underlying the evolution of tetrapod temporal fenestrations have been well investigated, few studies have investigated the developmental mechanisms responsible for differences in the pattern of temporal skull region. To determine what these mechanisms might be, we first examined how the five temporal bones develop by comparing embryonic cranial osteogenesis between representative extant reptilian species. The pattern of temporal skull region may depend on differences in temporal bone growth rate and growth direction during ontogeny. Next, we compared the histogenesis patterns and the expression of two key osteogenic genes, Runx2 and Msx2, in the temporal region of the representative reptilian embryos. Our comparative analyses suggest that the embryonic histological condition of the domain where temporal fenestrations would form predicts temporal skull morphology in adults and regulatory modifications of Runx2 and Msx2 expression in osteogenic mesenchymal precursor cells are likely involved in generating morphological diversity in the temporal skull region of reptiles.

Anatomical study of a human skull with multiple osteomas in a seventeenth-century Dutch still-life painting: bone morphology and artistic intention.

Skulls were frequently depicted in seventeenth-century Dutch still-life paintings. Skulls were interpreted as symbols of vanitas-meaning the evanescence of life-but their morphological features have received little attention. This study analyzed a skull with abnormal tumors in a seventeenth-century Dutch still-life painting by a renowned artist, Edwaert Collier (ca. 1642-1708), from anatomical, forensic, and pathological perspectives. The morphology of the cranium and teeth indicated that the skull likely belonged to a middle-aged female. We carefully diagnosed the abnormal masses as multiple osteomas on the skull and left femur, based on clinical studies and paleopathological literature, which reported lesions with a similar appearance to those observed in Collier's work. Furthermore, detailed observations of the cranial sutures and epiphyses of the long bones in his paintings revealed that the artist may have selected bones with a morphology that was suitable for the subject of vanitas. Collier repeatedly depicted the skull with metopism, the rare condition of having a persistent metopic suture in adulthood. A skull with a metopic suture is called Kreuzschädel, meaning the cross skull, because it forms a cruciform by connecting with the sagittal and coronal sutures. The artist might have chosen skulls with metopic sutures, which is reminiscent of the crucifixion of Christ, as an appropriate motif for the vanitas painting. This paper argues that anatomical analysis could explain the hidden meaning of the painting and disclose the fascinating collaborations between anatomy and art in the seventeenth-century Dutch Republic.

A morphometric study on skulls of Hasmer and Hasak sheep breeds / Un estudio morfométrico de cráneos de razas de ovejas Hasmer y Hasak

SUMMARY: The aim of the study was to investigate the head structures of two domestic sheep breeds (Hasak and Hasmer) in Turkey. Gender neutral eight adult Hasmer sheep of 45-66 kg and eight Hasak sheep breeds of 43-66 kg obtained from Bahri Dag˘das¸ International Agricultural Research Institute were used in this study. Measurements were made using digital caliper from 40 points on the skulls of both species. The skull of Hasmer sheep (265.56 ± 14.08) was longer than the skull of Hasak sheep (262.86 ± 9.65). However, the length of the arcus alveolaris maxillaris (77.01 ± 5.08), the length of the molar teeth (50.81 ± 1.22) and the length of the premolar teeth (26.16 ± 4.62) of Hasak sheep were compared to the Hasmer sheep (71.59, ± 5.25; 47.99 ± 3.64; 24.03 ± 3.76, respectively) was observed to be greater. According to these findings, although the skull length of Hasak sheep was shorter than that of Hasmer sheep and arcus alveolaris maxillaris in which molar and premolar teeth were placed was longer. In Hasmer sheep the values of greatest breadth of the foramen magnum, height of the foramen magnum (basion - opisthion), greatest neurocranium breadth-greatest breadth of the braincase (euryon - euryon) were higher than those of Hasak sheep. The difference between these values was also statistically significant (p <0.05). The lateral length of the premaxilla (nasointermaxillare- prosthion) parameter measured between these two species was statistically very important (p <0.01). In conclusion, in this study craniometric values depending on skull morphology of Hasmer and Hasak sheep which accepted as native breeds of Turkey were tried, to reveal similarities and differences with other sheep breeds in both amongst themselves.

El objetivo del estudio fue investigar las estructuras de la cabeza de dos razas de ovejas domésticas (Hasak y Hasmer) de Turquía. En este estudio se utilizaron ocho ovejas Hasmer adultas de género neutral de 45-66 kg y ocho ovejas de raza Hasak de 43-66 kg, obtenidas del Instituto Internacional de Investigación Agrícola Bahri Dagdas. Las mediciones en los cráneos de ambas especies se realiza-ron con caliper digital de 40 puntos. El cráneo de la oveja Hasmer (265,56 ± 14,08 mm) era más largo que el cráneo que el de la oveja Hasak (262,86 ± 9,65 mm). En las ovejas Hasak la longitud del arcus alveolaris maxillaris fue 77,01 ± 5,08 mm, la longitud de los dientes molares fue 50,81 ± 1,22 mm y la longitud de los dientes premolares fue de 26,16 ± 4,62 mm, en cambio en las ovejas Hasmer fue de 71,59 ± 5,25 mm; 47,99 ± 3,64 mm; 24,03 ± 3,76 mm, respectivamente. Según estos hallazgos, la longitud del cráneo de la oveja Hasak era más corta que la de la oveja Hasmer y el arcus alveolaris maxillaris en el que se colocaron los dientes molares y premolares era más largo. En ovinos Hasmer los valores de mayor amplitud del foramen magnum, altura del foramen magnum (basion - opisthion), mayor amplitud del neurocráneo-mayor amplitud de la caja craneana (euryon - euryon) fueron superiores a los de las ovejas Hasak. La diferencia entre estos valores también fue estadísticamente significativa (p <0,05). El parámetro de longitud lateral del premaxilar (nasointermaxillare-prosthion) medido entre estas dos especies fu estadísticamente significativo (p <0.01). En conclusión, los valores craneométricos en relación a la morfología del cráneo de las ovejas Hasmer y Hasak que se definieron como razas autóctonas de Turquía revelaron similitudes y diferencias con otras razas de ovejas.

Development of craniofacial superimposition: a review / Desarrollo de la superposición craneofacial: una revisión

SUMMARY: Craniofacial superimposition is a method for identifying individuals by using secondary data in order to identify a target group of persons before a DNA process can be used, or to identify an individual instead of using primary data in cases where DNA, fingerprint or dental records are not found. Craniofacial superimposition has continued to evolve, with various techniques, including computer-assisted and photography techniques, to help the operation be more convenient, faster and reliable. The knowledge of forensic anthropology is applied, with a comparison between anatomical landmarks. The study of developments in craniofacial superimposition using computer-assistance has yielded satisfactory results.

La superposición craneofacial es un método para identificar individuos mediante el uso de datos secundarios, se utiliza para identificar un grupo objetivo de personas, antes de que se pueda utilizar un proceso de ADN, o para identificar a un individuo en lugar de utilizar datos primarios en los casos en que no se cuenta con registros de ADN, huellas dactilares o dentales. La superposición craneofacial ha seguido evolucionando, con diversas técnicas, incluidas las técnicas fotográficas y asistidas por computador, para ayudar a que la operación sea más conveniente, rápida y confiable. Se aplica el conocimiento de la antropología forense, con una comparación entre hitos anatómicos. El estudio de la evolución de la superposición craneofacial con asistencia informática ha arrojado resultados satisfactorios.

A Simple and Descriptive Assessment of Morphology Based on the Horizontal Plane of the Pediatric Head and Creation of a Normative Database in Japanese Children 6 Years Old and under: Horizontal Vector Analysis.

We herein introduce horizontal vector analysis, a simple method for assessing cranial morphology based on measurement of the head's horizontal plane, and use this method to establish normal cranial morphology in Japanese children Computed tomography scans taken in 2010-2019 in healthy Japanese children aged ≤ 6 years. The two measurement planes were parallel to the orbitomeatal plane: namely, a plane passing through the dorsum sellae (DS) and the plane superior to that with the maximal area (Max plane). A protractor was used to circumferentially measure the lengths from the central point to the outer surface of the skull. A total of 487 images were extracted. The distances between the DS and Max planes were consistently almost 30 mm for each age group, so we fixed the Max plane as the plane 30 mm superior to the DS plane. Finally, we established datasets of normal values for each age group and sex. Using these norms, perioperative evaluation of various cranial deformities could be performed more easily and circumstantially.