Search Results (155)

Fenestrations of mammalian skull bones are rare and poorly understood, particularly within the parietal bone. In bats—a group characterised by advanced sensory specialisation and echolocation—superficial modifications of the cranial vault may have functional significance, yet their occurrence and organisation remain insufficiently documented. In this study, we describe an exceptional fenestrated complex in the posterolateral parietal bone of Plecotus auritus, comprising structural elements not previously recorded within Vespertilionidae. The aim of the study was to characterise in detail the morphology, topography, and variability of the surface structure termed Fenestras Elisabeth (nova structura), with particular emphasis on its relationship with the auditory region and its potential biomechanical–acoustic significance. The material consisted of ten skulls of P. auritus, examined using micro-CT scanning, 3D reconstruction, and qualitative analysis of fenestrated structures and their topographic relationships. Within the posterolateral parietal region, we identified an extensive and repeatable fenestrated complex comprising numerous fenestrae parietales Elisabeth, paired fenestrula Elisabeth, a central depression (recessus acousticus parietalis), and a bordering fissure (fissura occipitalis mastoidea, nova structura topographica). The complex exhibited a stable spatial organisation despite individual variation in the number and shape of the openings. All fenestrations were confined to the posterolateral zone, and the contact between the fenestrae and the fissura occipitalis mastoidea represented a diagnostic feature. Our analysis suggests that the Fenestras Elisabeth complex may be associated with combined biomechanical and acoustic constraints: (1) a biomechanical role—reducing strain in the parietal lamina during movements of the extremely mobile and elongated pinnae; and (2) an acoustic role—modulating micro-vibrations transmitted to the inner-ear structures. Individual variability and lateral asymmetry of fenestration patterns indicate a high degree of adaptive plasticity in this region of the skull. This study provides the first documentation of a large, structurally organised parietal-bone fenestration complex in Plecotus auritus, expanding current knowledge of bat cranial morphology and suggesting a likely functional significance for these previously unknown bony structures. Full article

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

Background/Objectives: The sella turcica (ST) is a central craniofacial and endocrinological landmark whose morphology reflects both local skeletal development and systemic influences. Alterations in its form have been observed in various genetic syndromes, including trisomy 21 (Down syndrome, DS). Considering the characteristic craniofacial morphology of DS, this review aimed to evaluate whether individuals with DS present distinctive morphometric features and shape variants of the ST compared with non-syndromic populations and to discuss their diagnostic and clinical relevance. Methods: A systematic literature search was carried out in PubMed, the Cochrane Library, Web of Science, Wiley, MDPI, and Google Scholar on 8 May 2024. Search terms included “sella turcica,” “Down syndrome,” and “morphology.” Studies employing lateral cephalograms, cone-beam computed tomography (CBCT), or computed tomography (CT) to assess ST morphology were included when quantitative or qualitative comparisons with control groups were available. The review followed the PRISMA 2020 guidelines and was prospectively registered in PROSPERO (CRD42024580071). Results: Only six studies fulfilled the inclusion criteria. Increased ST dimensions and a predominance of U-shaped and J-shaped variants in individuals with DS compared with controls were most frequently reported. Although the studies differed in methodology, the findings consistently indicated characteristic enlargement and remodeling of the ST in trisomy 21. Conclusions: Individuals with Down syndrome exhibit distinctive sella turcica morphology characterized by increased size and specific shape variants. The evidence base remains small and heterogeneous, with few observational studies and mixed age groups and imaging modalities, which limits the strength and generalizability of the conclusions. The present study aims to provide a modern, updated systematic review of current evidence on sella turcica morphology in patients with Down syndrome, to identify reported patterns of variation, and to explore their clinical and diagnostic significance. Recognition of these features enhances diagnostic accuracy in craniofacial evaluation, facilitates comprehensive orthodontic, endocrine, and oncological assessment, and advances understanding of cranial base development within the context of genetic syndromes. Full article

Head posture assessment commonly involves measuring cranial angles, with photogrammetry favored for its simplicity over CT scans or goniometers. However, most photo-based measurements remain manual, making them time-consuming and inefficient. Existing automatic measuring approaches often requires specific markers and clean backgrounds, limiting their usability. We present AutoMCA, a robust automatic measurement system for cranial angles using accessible markers and tolerating typical indoor backgrounds. AutoMCA integrates MediaPipe Pose, a machine-learning solution, for head–neck segmentation and applies color thresholding and morphological operations for marker detection. Validation tests demonstrated Pearson correlation coefficients above 0.98 compared to manual Kinovea measurements for both the craniovertebral angle (CVA) and cranial rotation angle (CRA), confirming high accuracy. Further validation on individuals with neck disorders showed similarly strong correlations, supporting clinical applicability. Speed comparison tests revealed that AutoMCA significantly reduces measurement time compared to traditional photogrammetry. Robustness tests confirmed reliable performance across varied backgrounds and marker types. In conclusion, AutoMCA measures head posture efficiency and lowers the requirements for instruments and space, making the assessment more versatile and applicable. Full article

The skull provides essential diagnostic features for species identification and sex determination. Cranial sexual dimorphism in guinea pigs (Cavia porcellus) is particularly important to understand, as these animals are frequently used in experimental research and veterinary practice, yet detailed morphometric evaluations remain limited. This study aimed to assess cranial size and shape variation between sexes using three-dimensional geometric morphometric (GM) methods. Computed tomography scans of 30 clinically healthy guinea pigs were used to reconstruct three-dimensional skull models. Twenty-one anatomical landmarks were digitized, and the dataset was subjected to generalized Procrustes analysis, followed by principal component analysis, Procrustes ANOVA, and regression-based allometric assessments. The results revealed pronounced sexual dimorphism. Males exhibited significantly larger centroid sizes and more robust cranial morphologies, whereas females presented smaller and more gracile skull forms. Procrustes ANOVA confirmed significant shape differences between sexes (p < 0.01), with size being the primary driver of morphological divergence. Body weight had a weaker but detectable influence on cranial variation, although its effect diminished after accounting for centroid size (R²: 0.085). These findings demonstrate that three-dimensional geometric morphometrics can effectively detect subtle patterns of cranial dimorphism in guinea pigs. Beyond their anatomical relevance, the results provide a valuable reference for veterinary sciences, taxonomy, and future biomedical research requiring precise morphological characterization. These findings show that three-dimensional geometric morphometrics can effectively detect subtle patterns of sexual dimorphism in cranial shape, which is particularly relevant for sex identification in skeletal collections and for the development of comparative anatomical databases in veterinary and experimental research. Full article

The Daurian ground squirrel (Spermophilus dauricus) is an important animal model that is frequently used by researchers studying the physiological ecology of hibernation in China. There has been considerable controversy regarding the classification of its subspecies, and there is a lack of relevant comparisons of morphometric data. To clarify this issue, this study aims to systematically compare five external morphological traits and 20 cranial traits of S. dauricus collected from 10 locations within China to assess the phenotypic differentiation of S. dauricus within China. Through morphological cluster analysis (MCA), discriminant function analysis (DFA), and principal component analysis (PCA), the samples from 10 locations (FK, n = 5; JZ, n = 11; DQ, n = 7; KP, n = 6; HEB, n = 4; EE, n = 10; CF, n = 3; ZB, n = 6; CD, n = 8; WL, n = 7) can be divided into three geographical populations: the Northeast population (NE); the Inner Mongolia population (IM); and the Hebei population (HB). There is significant morphological variation in four external traits and 19 cranial traits among populations within the species. Specifically, the NE population presented greater body length, tail length, and cranial dimensions. The IM population has the shortest tail, whereas the HB population has the smallest overall body size—its tail length, however, falls between those of the NE and IM populations. These morphological differences may be related to differences in habitat. This study revealed a significant correlation between environmental factors and the morphological traits of S. dauricus. Redundancy analysis (RDA) further revealed that the mean annual temperature (MAT) and mean annual precipitation (MAP) significantly affected the morphological traits of S. dauricus. This study challenges the current subspecies classification, clarifies the geographical morphological variation pattern of S. dauricus, reveals the influence of the environment on the differentiation of its morphological traits, and provides new morphological evidence for resolving the controversy over its subspecies classification. Full article

Background/Objectives: Complex aneurysms of the posterior inferior cerebellar artery (PICA) remain challenging because of their deep location, variable morphology, and proximity to critical neurovascular structures. Although endovascular therapy is preferred, its feasibility is limited in wide-necked, fusiform, or dissecting lesions. We describe our tertiary referral hospital single-center experience with tailored microsurgical and endovascular strategies—emphasizing occipital artery–PICA (OA-PICA) bypass, transcondylar fossa craniotomy, and cerebellomedullary fissure opening—and analyze perioperative factors that influence outcome. Methods: All consecutive patients treated for PICA origin or distal-PICA aneurysms between January 2021 and April 2025 were retrospectively reviewed. Demographics, aneurysm characteristics, procedure type, antithrombotic regimen, complications, diffusion-weighted MRI findings, and 3-month modified Rankin Scale scores were collected. Results: Twelve aneurysms (mean age 61.4 ± 15.2 years; 8 women) were treated: trapping + OA-PICA bypass in 5, direct clipping in 2, flow diverter in 1, endovascular parent artery occlusion in 2, coil embolization in 1, and a hybrid bypass-plus-coil strategy in 1. Two cases were ruptured aneurysms. Perioperative aspirin was used in 2/5 bypass cases; heparin was added in one hybrid case. Asymptomatic PICA-territory infarcts occurred in the three bypasses performed without antiplatelet therapy (one with intra-anastomotic thrombus). No leaks or subcutaneous collections of cerebrospinal fluid were encountered, and no graft occlusions were observed. At 3 months, 9/12 patients achieved a good outcome (mRS 0–2); among them, only one patient with subarachnoid hemorrhage (SAH) experienced postoperative worsening of the mRS. Two cranial nerve palsies (one permanent, one transient) and one wound site hematoma (heparin-associated) resolved without sequelae. Conclusions: Meticulous operative planning allows safe treatment of complex PICA aneurysms. Perioperative aspirin appears beneficial for OA-PICA bypass, whereas perioperative heparin increases bleeding risk. Individualized selection of endovascular, microsurgical, or combined strategies yields favorable early neurological outcomes in this demanding subset of cerebrovascular disease. Full article

Horses were widely distributed in North America during the Pleistocene epoch and their fossil remains are common in sedimentary deposits of this age. Despite their rich fossil record, the systematics and taxonomy of North American Pleistocene horses remain unresolved. We evaluated a large sample of cranial and postcranial horse fossils of Irvingtonian and Rancholabrean North American Land Mammal Age. In this study, we present Part 1 of our evaluation, which centers on caballine horses, Equus (Equus). We present data (measurements and photographs) and analyses (Simpson’s ratio diagrams, scatter diagrams, and anatomical comparisons) that reveal morphological variation in North American caballine horses. These analyses serve as the basis for recognizing different morphospecies: E. (E.) scotti, E. (E.) alaskae, E. (E.) lambei (the latter two possibly representing “ecological variants” of a single species), E. (E.) niobrarensis, E. (E.) pacificus, and E. (E.) complicatus. How these morphospecies (or chronospecies or ecological variants) were phylogenetically related remains to be evaluated. Equus (E.) hatcheri may be considered as a morphological variant or chronological variant of E. (E.) niobrarensis. Equus holmesi is considered a junior synonym of E. (E.) scotti, while E. bautistensis may be regarded as a junior synonym of E. (E.) pacificus. Equus laurentius is a junior synonym of E. (E.) caballus, a synonymy proposed previously in other studies. We are uncertain about the nature of E. midlandensis. In addition, we identify morphometric and anatomical features that distinguish between Equus (Equus), North American Equus (Amerhippus), and Equus (Hesperohippus) mexicanus. This study aims to advance our understanding of the taxonomy of North American Pleistocene horses, providing a thoroughly documented catalogue as a basis for further studies. Full article

Background: The human skull has a very complex and diverse structure, and morphological characteristics vary by population. The purpose of this study is to comprehensively analyze the cranial morphology using postmortem computed tomography (PMCT), and to identify anatomical characteristics through a multifaceted approach in Koreans. Methods: 358 PMCT cross-sectional images (179 males, 179 females) provided by the National Forensic Service were analyzed, and the average age was 55.1 ± 18.9 years. The maximum cranial length was divided by the maximum cranial width and multiplied by 100 to calculate the cranial index (CI). Petrous ridge–midline angle (PMA) was measured as the angle between the petrous ridge and the midline. Results: In both the classification of skull shape using CI and PMA, the brachycranic type showed the highest frequency (p < 0.001). Classified by CI, there were no significant differences in frequency by sex (p = 0.533), or age (p = 0.110). However, classified by PMA, the frequency of the brachycranic type in men was significantly higher than in women (p = 0.022), and there was a significant difference in the frequency of cranial morphology by age (p < 0.001). Conclusions: The results of cranial morphology classification targeting Koreans are expected to provide useful basic data for clinical and forensic use. Full article

This study aimed to characterize the computed tomographic (CT) dimensions and contrast attenuation properties of the equine eye. CT scans from 21 horses without ocular abnormalities were analyzed to obtain detailed ocular measurements and attenuation values. In addition, cranial measurements, such as nasal–occipital length and zygomatic width, were incorporated to explore potential anatomical relationships between the skull and intraocular structures. Although most correlations between cranial and ocular parameters were weak, statistically significant associations—particularly those involving lens dimensions and anterior chamber measurements—suggest that skull morphology may exert a subtle influence on ocular anatomy. Full article

The stylohyoid complex (SHC), comprising the styloid process (SP), stylohyoid ligament, and lesser horn of the hyoid bone, arises from Reichert’s cartilage and plays a central role in head and neck organization. Although anatomically small, it occupies a strategic position in the parapharyngeal space, linking neural, vascular, and visceral compartments. This review integrates embryological, comparative, anatomical, and clinical perspectives to provide an updated synthesis of SHC morphology and significance. Developmental studies highlight the early segmentation of Reichert’s cartilage, its transient relationships with the otic capsule, facial canal, and carotid arteries, and its role in shaping muscular and fascial compartments. Comparative anatomy demonstrates the evolutionary transition from a continuous ossicular chain to a vestigial human structure, reflecting a trade-off between rigidity and vocal tract flexibility. In humans, the SHC exhibits marked variability in length, angulation, segmentation, and ligamentous ossification, which directly influence its spatial relationships with the internal and external carotid arteries, the internal jugular vein, and the lower cranial nerves. These variations underpin the clinical spectrum of Eagle’s syndrome and vascular complications, including carotid artery dissection and jugular compression syndromes. Recognition of these embryological origins, evolutionary trajectories, and anatomical variants is essential for accurate diagnosis, imaging interpretation, and surgical planning. As both an embryological remnant and a clinical landmark, the SHC bridges fundamental anatomy with practical implications for imaging, diagnosis, and surgery. Full article

Understanding the anatomy of the avian nasal cavity and paranasal sinuses is essential for diagnosing respiratory diseases and interpreting imaging findings. However, detailed tomographic descriptions of these structures are scarce in seabirds. This study aimed to provide an anatomical and radiological characterization of the nasal cavity and associated sinuses of the yellow-legged gull (Larus michahellis atlantis). Computed tomography (CT) was performed on eight cadaveric specimens using a 16-slice helical scanner with bone and pulmonary window settings. Anatomical cross-sections of the same heads were subsequently obtained to correlate and validate CT findings. CT imaging clearly delineated major nasal structures, including the rostral, middle, and caudal nasal conchae, the nasal septum, and the infraorbital sinus, as well as their connections to adjacent cranial bones. The integration of CT and anatomical cross-sections provided detailed spatial relationships and accurate visualization of the internal nasal architecture. This study demonstrates the value of CT for examining avian cranial anatomy and provides a morphological reference framework that may aid in diagnosing nasal and sinus pathologies in seabirds. Full article

Background and Objectives: Advanced gynecomastia/pseudogynecomastia (Simon grades IIb–III) in post-bariatric patients presents both esthetic and technical challenges. Conventional excisional methods often result in flattened chest contours, extensive scarring, and loss of nipple–areolar complex (NAC) sensation. There is a growing need for conservative, tissue-preserving strategies that respect the unique morphology of massive weight-loss patients. Materials and Methods: This consecutive case series included 15 male patients (median age: 38 years, IQR 36.5–39.5) with advanced gynecomastia/pseudogynecomastia and stable weight loss following bariatric surgery. All underwent a glandular transposition technique, preserving the NAC on a pedicle based on thoracic perforators and avoiding free grafting. Redundant lower-pole skin was excised, a new NAC site was created cranially, and the gland was repositioned beneath a dermo-adipose flap. Outcomes included complication rates, patient satisfaction, and changes in BODY-Q chest appearance scores. Results: No major complications occurred. NAC viability and sensation were preserved in all patients. One patient required secondary revision for residual contour bulging, while three developed minor hematomas that resolved spontaneously. At 3 months, the median Likert satisfaction score improved from 2 (IQR 2–3) preoperatively to 5 (IQR 4–5) postoperatively (p < 0.001, Wilcoxon signed-rank test). BODY-Q chest appearance scores improved significantly from 31 (IQR 28–35) to 78 (IQR 74–82) (p < 0.001). External observers preferred postoperative results in 90% of randomized photo-pair comparisons. Conclusions: Glandular transposition is a safe, reproducible, and esthetically effective technique for advanced gynecomastia/pseudogynecomastia in post-bariatric men. By preserving glandular continuity and avoiding free NAC grafting, this method achieves natural chest projection, maintains nipple sensitivity, and provides high patient satisfaction with minimal complications. It represents a compelling alternative to conventional radical excision strategies. Full article

Background/Objectives: Morphological defects such as limb malformations, cranial asymmetries, loin deviations, jaw misalignments, and navel irregularities are associated with early culling and reduced productivity in beef cattle. In Bos taurus indicus such as Nellore, the genetic basis of these traits remains poorly characterized. This study aimed to investigate the genetic architecture of six morphological defects in Nellore cattle, namely feet and legs malformation, chamfer asymmetry, fallen hump, loin deviation, jaw misalignment, and navel irregularities, via a genome-wide association study (GWAS) approach tailored for binary traits. Methods: Depending on the trait, the number of genotyped animals analyzed ranged from 3369 to 23,206, using 385,079 SNPs (after quality control). Analyses were conducted using a linear mixed model framework adapted for binary outcomes. Results: Significant associations were identified for four traits: feet and legs, chamfer, hump, and loin. No significant markers were detected for jaw or navel defects, likely due to lower sample sizes and trait incidence. Gene annotation revealed 49 candidate genes related to feet and legs, 4 for chamfer, 4 for hump, and 6 for loin. Conclusions: Candidate genes were enriched for biological functions, including bone remodeling, muscle development, lipid metabolism, and epithelial organization. Overlaps with QTL related to conformation, feed intake, reproductive traits, and carcass quality were also observed. These findings provide novel insights into the genetic control of morphological defects in Nellore cattle and may inform breeding strategies aimed at improving structural soundness. Full article

Background/Objective: Neuronal intranuclear inclusion disease (NIID) is characterized by widespread deposition of eosinophilic intranuclear inclusions in multiple systems throughout the body. The aim of this study was to investigate the clinical and phenotypic features of NIID, with a focus on the potential association between the morphological features of fibrils formed by polyG (polyglycine) proteins and cognitive dysfunction in patients with NIID. Methods: This study involved a retrospective collection of clinical data from 15 patients with NIID harboring GGC repeat expansions in the NOTCH2NLC (Notch 2 N-Terminal Like C) gene (including symptoms, signs, biochemical markers, cranial MRI, MMSE, and MoCA cognitive scores). All patients underwent skin biopsy, with one additional autopsy of brain tissue. Some skin samples were stained with hematoxylin and eosin (H&E) and immunohistochemistry (IHC) staining with anti-p62 antibody. The remaining skin samples and brain tissue samples obtained from autopsies were analyzed using anti-p62 antibody immunofluorescence (IF) staining and transmission electron microscopy (TEM). The number of GGC repeats was quantified using repeat primer PCR (RP-PCR). Based on ultrastructural characteristics (morphology and diameter), inclusion fibers were classified into two subtypes, and differences in the severity of cognitive impairment between subtypes were compared. Results: The majority of patients in this cohort with NIID were female (73.3%), with an average age of onset of 61.06 ± 7.67 years. The core clinical manifestations were cognitive decline (93.3%) and autonomic dysfunction (93.3%). Cranial MRI revealed characteristic DWI “ribbon sign” in 93.3% of patients, accompanied by lateral ventricle enlargement (93.3%), cerebellar atrophy (86.6%), and high T2-FLAIR signal in the corpus callosum (93.3%). All patients were found to have pathogenic GGC amplification in the NOTCH2NLC gene (median 115, range 88–210). Skin/brain tissue pathology confirmed p62-positive nuclear inclusions, and transmission electron microscopy revealed two fiber subtypes for the first time: type A (Long, thin filamentous, 202.38 ± 42.35 nm) and type B (short rod-shaped, 73.08 ± 11.56 nm). Group analysis indicated that the diameter of fibers was significantly larger in the cognitive impairment group (p < 0.05), and the type B fiber group had lower cognitive levels (p < 0.05) and larger diameters (p < 0.05), suggesting a strong association between type B fibers and severe cognitive impairment and poor prognosis. Conclusions: The presence of two different forms of fibrils, type A and type B, in the inclusion bodies of NIID patients, and the poorer cognitive level of NIID patients in the type B group than that of type A suggest that type B fibrils can be used as a novel pathological marker of severe cognitive impairment and poor prognosis in NIID. Full article