Purpose The median cubital vein (MCV) is frequently used for venipuncture, but anatomical variation and tourniquet application can alter its relationship to the brachial artery and median nerve. This study used ultrasonography to characterise these effects across sex and ethnicity. Methods Sixty healthy adults (28 men, 32 women; aged 18–46 years) from South Asian, Middle Eastern and North African (MENA), Sub-Saharan African (SSA), and other backgrounds underwent ultrasonographic assessment (GE LOGIQ system, 12 MHz linear transducer) of MCV diameter and its distance from the brachial artery, median nerve, and skin surface, before and after tourniquet application. Results Tourniquet application significantly increased MCV diameter and its distance from the brachial artery and median nerve (p<0.05), with no significant change in skin depth. MCV diameter did not differ significantly by sex; however, after tourniquet application, males showed significantly greater distance from the brachial artery and median nerve than females (p<0.05). MCV diameter differed significantly across ethnic groups after tourniquet application (one-way ANOVA, p=0.037), with MENA participants having the largest and SSA participants the smallest mean diameter; no other parameter differed by ethnicity. Anatomical variants included MCV absence (8.3%), MCV coursing deep to the bicipital aponeurosis (3.6% of visualized veins), and the brachial artery or median nerve lying directly beneath the MCV (5.5%). Conclusion Tourniquet application, sex, and ethnicity significantly influence MCV anatomy and its neurovascular relationships. Ultrasonography reliably detects clinically important variants that could compromise venipuncture safety, supporting its selective use before vascular access in high-risk patients.
Purpose Transoral endoscopic surgery of the parapharyngeal space (PPS) reduces morbidity compared with external approaches, but the narrow surgical corridor, the “inside-out” viewing angle, and the lack of visible bony landmarks increase the risk of hemorrhage, airway compromise, and cranial nerve injury. This study aimed to describe the endoscopic identification of the styloglossus muscle (SGM) via the transoral route, to evaluate its relationship with high-risk structures (external carotid artery, lingual nerve), and to propose an SGM-based orientation protocol for transoral endoscopic PPS surgery. Methods A descriptive cadaveric anatomical study was performed on 10 fresh adult cadaveric heads (20 sides). Transoral endoscopic dissection of the PPS was carried out layer by layer, from the mucosa through the superior pharyngeal constrictor muscle to the prestyloid fat pad. Distances from the SGM to the lateral pharyngeal mucosa, to the lingual nerve at two anatomical levels, and to the external carotid artery were measured and expressed as mean ± SD and range (minimum–maximum). Results The SGM was identified in 100% of dissected specimens as a muscular bundle coursing obliquely from the styloid region anteromedially toward the tongue base, deep to the lateral pharyngeal wall, and became visible early after dissection of the prestyloid fat pad. The external carotid artery and its branches (lingual and facial arteries) coursed posterior to the SGM, while the lingual nerve ran superolateral to it and approached it more closely toward the tongue base. Conclusion Within this cadaveric cohort, the SGM was a readily identifiable and consistent anatomical landmark under transoral endoscopy that may provide orientation during PPS access, particularly for recognizing the posterior limit of the prestyloid compartment before entering the vascular-rich poststyloid region. Its value as a surgical safety landmark requires confirmation in clinical studies.
Background True versus pseudo-trifurcation of the celiac trunk (CT) is assigned by visual impression, without a numerical threshold, despite its surgical and endovascular relevance. We aimed to derive a candidate measurement-based criterion and to test whether a structure crossing the proximal trunk relates to branching pattern. Methods Thirty-six formalin-fixed cadavers were dissected. We measured the distance from the CT's aortic origin to its first branch (L1) and to complete separation of all three branches (L2), and their difference (ΔL = L2 − L1). Trifurcation was classified qualitatively before measurement and used as the reference standard for ROC analysis of ΔL. All dissections, classifications and measurements were performed once, by a single unblinded observer. The threshold, derived and evaluated in the same 27 trunks, was internally validated by bootstrap resampling (2000 replicates). Results Of 27 assessable trunks, 10 (37.0%) were true and 17 (63.0%) pseudo-trifurcations. ΔL gave an apparent AUC of 0.976 (cutoff >2.5 mm; sensitivity 100%, specificity 90%) and an optimism-corrected AUC of 0.976 with corrected sensitivity 98.3% and specificity 88.0%. Youden's J was maximal across a plateau (0.6–4.38 mm) of which 2.5 mm is only the midpoint; one specimen caused the entire loss of specificity. Variant branching (61.1%) and crossing structures (66.7%) were mutually independent (p > 0.05). Conclusions ΔL reproduced an independent qualitative classification with high derivation-sample accuracy, but remains a candidate criterion only: the threshold is poorly determined and was obtained by one unblinded observer without repeated measurements. Independent blinded confirmation and prospective validation against imaging are required before clinical use.
Background/objective Stature estimation from skeletal remains is a fundamental component of biological profile construction in forensic anthropology. When long bones are unavailable, the cranium represents a viable alternative source. This study compared linear regression (LR), support vector regression (SVR), and random forest (RF) for stature estimation from cranial computed tomography (CT) measurements in Northeastern Thai adults. Methods A total of 240 subjects (120 males, 120 females) aged 20–94 years were included. Eight cranial dimensions were measured from CT reconstructions, and models were developed for combined, male, and female groups using seven cranial measurements selected on the basis of significant correlations with stature, with all models validated using leave-one-out cross-validation. Results Seven of eight cranial measurements correlated significantly with stature in the combined sample. RF achieved the highest predictive accuracy (R2 = 0.424, RMSE = 6.975 cm), followed by LR (R2 = 0.414, SEE = 7.109 cm) and SVR (R2 = 0.382, RMSE = 7.227 cm), with RF producing the narrowest limits of agreement in Bland–Altman analysis. In the male subsample, LR outperformed both ML models (R2 = 0.314, SEE = 6.206 cm). Female-specific models demonstrated limited predictive capacity across all approaches (R2 ≤ 0.063). Conclusion Cranial CT measurements provide a viable basis for stature estimation in this population. RF offers superior performance in the combined sample, while LR remains a practical and interpretable alternative. The combined model is recommended when biological sex has not been established.
Background The interatrial septum may present several anatomical variants, including the left-sided septal pouch (LSSP), right-sided septal pouch (RSSP), and a smooth septum. The aim of this study was to identify telocyte-like cells in these variants and to evaluate their immunophenotype and tissue distribution. Materials and methods The study was performed on 75 human hearts obtained during forensic autopsy and without gross structural abnormalities (38 LSSP, 17 RSSP, and 20 smooth septa). Double-immunofluorescence staining was carried out for CD34 in combination with PDGFRα, vimentin, and CD117 (c-Kit), and the material was examined using confocal microscopy with additional quantitative image analysis. Results Telocyte-like cells, recognized on the basis of elongated morphology and CD34 co-expression with PDGFRα or vimentin, were found in all examined septal variants. No CD34/CD117 co-expression was detected. Quantitative analysis showed no significant differences between LSSP, RSSP, and smooth septum in the proportion of CD34/PDGFRα- or CD34/vimentin-positive cells. Assessment of tissue distribution demonstrated the presence of telocyte-like cells in all major tissue layers and structural components of each septal variant, including the endocardium, fibroelastic connective tissue, and myocardial component. No evident qualitative differences in their distribution were observed between variants, except for a lower apparent density in the fibroelastic anchor zone at the fusion point of the septal pouches. Conclusions Telocyte-like cells are consistently identifiable across the human LSSP, RSSP, and smooth interatrial septum. Their comparable distribution suggests preservation of a baseline stromal framework across these anatomical configurations and provides a basis for further studies of septal remodeling.
Background: The quadriceps femoris muscle group demonstrates considerable anatomical variation, among which the tensor vastus intermedius (TVI) has been increasingly recognized as a distinct muscular component. Methods and results: The present case report describes bilateral, well-defined TVI identified during routine cadaveric dissection. The muscle was located between the vastus lateralis and vastus intermedius on both sides, displaying a distinct muscle belly and a separate fascial plane. The morphology and location were symmetrical on both sides, with no obvious differences in fibre orientation. Conclusion: A well-defined Vastus lateralis type (VL type) TVI muscle was identified during cadaveric dissection. Its recognition has important implications for surgical approaches to the anterior thigh, interpretation of imaging studies, and understanding of quadriceps biomechanics. To our knowledge, this is the first reported case of a bilateral tensor vastus intermedius from Sri Lanka.
Background: Psychological well-being is increasingly recognized as a determinant of mental and physical health, yet its assessment remains dominated by subjective self-reports constrained by cultural bias and temporal variability. Neuroimaging offers the potential for identifying objective indicators, although its application to psychological well-being remains at an early stage. Aim: To synthesize structural, functional, and molecular neuroimaging evidence of psychological well-being and evaluate its readiness for biomarker development. Methods: A narrative review was conducted integrating evidence from structural imaging (MRI, diffusion imaging), functional modalities (fMRI, EEG, MEG), and molecular imaging (PET), alongside psychometric assessments of well-being and affective states. Results: Structural and diffusion imaging link white matter integrity, particularly in the corpus callosum and fronto-limbic tracts, with adaptive functioning. Functional MRI and electrophysiological studies reveal connectivity and oscillatory dynamics involving the prefrontal cortex (PFC), insula, and limbic regions that support affect regulation. Molecular imaging highlights neurotransmitter systems, including dopaminergic and serotonergic pathways, underlying motivation and mood. Across modalities, converging evidence identifies the PFC, insula, limbic regions, and corpus callosum as key neural correlates of well-being. However, the evidence is largely based on cross-sectional designs, with small effect sizes, methodological heterogeneity, and substantial overlap with stress and psychopathology, which limits specificity. Conclusion: Neuroimaging provides valuable insights into the neural correlates of psychological well-being, but current evidence does not yet meet criteria required for clinically meaningful biomarkers. Progress requires longitudinal multimodal designs, standardised protocols, cross-cultural validation, and improved integration with psychometric and physiological measures to achieve clinically meaningful and predictive biomarkers.
Background The lateral circumflex femoral vein is ligated and transected to access the proximal portion of the deep femoral artery during femoral tripod revascularization. However, few studies have been conducted on the lateral circumflex femoral vein, and data are lacking on the relationship between the lateral circumflex femoral vein and the deep femoral artery. The aim of this study was to investigate the relationship between the lateral circumflex femoral vein and the deep femoral artery in order to propose a classification. Materials and methods This was an anatomical, cross-sectional, and descriptive study. It spanned a five-year period from February 2021 to January 2026. Results The most frequent relationship was a single lateral circumflex femoral vein passing anterior to the deep femoral artery, with a prevalence of 51.1%. The single lateral circumflex femoral vein passed posterior to the deep femoral artery in 11.7% of cases. Two lateral circumflex femoral veins, both passing either anterior or posterior to the deep femoral artery, were observed in 20% and 5% of cases, respectively. In 3.9% of cases, one of the two veins passed anterior to the deep femoral artery and the other posterior. The presence of three lateral circumflex femoral veins, all three passing anterior to the deep femoral artery, was observed in 1.7% of cases. The deep femoral artery passed between the three lateral circumflex femoral veins in 5.5% of cases. Conclusion The lateral circumflex femoral vein exhibits variations in its number and its relationship to the deep femoral artery. Understanding these variations is important for addressing the deep femoral artery in femoral tripod reconstruction techniques.
Background: The atlas vertebra (C1) has a close anatomical relationship with the vertebral artery through the transverse foramen. Incomplete osseous closure of this canal, described as an unclosed transverse foramen (UTF), may modify the expected bony boundaries around the vertebral artery. Objective: This systematic review and meta-analysis estimated the prevalence of UTF in anatomically modern humans and summarized its anatomical and potential clinical implications. Methods: Searches were conducted in MEDLINE, CINAHL, Web of Science, Scopus and complementary sources following PRISMA 2020 and evidence-based anatomy recommendations. Eligible studies were original human anatomical, osteological, cadaveric, skeletal or imaging-based studies that reported C1-specific UTF with an extractable numerator and denominator. Methodological quality was assessed using the AQUA tool. Pooled prevalence was estimated using a random-effects model with logit-transformed proportions. Results: Six studies were included in the quantitative synthesis. The pooled prevalence of UTF was 8.8%, with negligible between-study heterogeneity. Methodological quality was predominantly favorable. Conclusions: UTF is an uncommon but recurrent anatomical variant of the atlas. Current evidence does not establish isolated UTF as an independent cause of symptoms. The variant should nevertheless be recognized in anatomical description, radiological reporting and preoperative planning for upper cervical procedures.
Background: The parotid gland, the largest of the major salivary glands, plays a crucial role in oral and digestive physiology by producing enzyme-rich serous saliva. Despite decades of research, variations reported among the authors on the timeline of glandular duct appearance, canalization, and the onset of functional maturation persist. Thus, the present study aimed to address the details of duct formation, acinar maturation, and glandular differentiation during the fetal period in parotid development. Methods: This observational study included 28 fetal samples from stillborn and medically terminated pregnancies, selected based on inclusion and exclusion criteria. Necessary protocols, such as ethical clearance, dissection of the specimen, parotid tissue procurement, tissue processing, and staining (hematoxylin and eosin, MassonGoldner), were followed as per the standard guidelines. Results: In the first trimester (8-12 weeks), development initiates with solid epithelial cords from the oral ectoderm projecting into the mesenchyme, lacking lumina or organization, progressing to primitive canalization by 16-20 weeks. The second trimester (13-24 weeks) shows branching ducts, emerging serous acini with initial secretory granules, and primitive myoepithelial cells amid a reducing mesenchymal stroma. By the third trimester (24-40 weeks), well-formed pyramidal serous acini with abundant zymogen granules, a completely branched ductal tree, and mature contractile myoepithelial cells appear similar to near-adult morphology. Conclusion: Trimester-specific data enhances further understanding of parotid gland development and its application in congenital anomaly diagnostics and regenerative medicine. Understanding the developmental determinants of glandular architecture and neurovascular relationships improves procedural accuracy in maxillofacial surgery.
Background: Cerebral small vessel disease (CSVD) is a major cause of vascular cognitive impairment, yet early-stage alterations remain insufficiently characterized. This study investigated the relationship between behavioral deficits, hippocampal microstructure, and histopathological changes in a preclinical CSVD model. Methods: Male stroke-prone spontaneously hypertensive rats (SHRSP) and Wistar Kyoto (WKY) controls were evaluated at 8, 14, and 42 weeks. Behavioral assessments included open field, novel object recognition, and Morris's water maze. Brain MRI was performed using a 3.0 T system with diffusion tensor imaging (DTI), followed by region-of-interest analysis of the hippocampus. Histological evaluation included hematoxylin and eosin (H&E) and Nissl staining. Results: SHRSP demonstrated age-associated behavioral alterations, including reduced locomotor activity (strain & times; age: p = 0.013), preserved recognition memory at early stages but declined at 42 weeks, and impaired spatial learning with absent acquisition improvement in aged animals. Notably, hippocampal DTI metrics remained unchanged across the examined experimental time points, with no significant effects of strain or age on fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), or radial diffusivity (RD) (all p > 0.25). Whole-brain analyses yielded non-significant findings similarly. Histologically, enlarged perivascular spaces (ePVS) were consistently observed, while microbleeds and hemosiderin deposition were absent. Hippocampal thickness (CA1, CA3, dentate gyrus) was preserved; however, selective neuronal loss was detected in the CA3 subfield of aged SHRSP (42 weeks). Conclusion: Behavioral decline was observed despite the absence of detectable hippocampal microstructural alterations using conventional DTI metrics, suggesting that functional impairment may emerge before abnormalities become evident within the sensitivity limits of the current imaging framework. These findings suggest that early CSVD involves subtle cellular and vascular dysfunction not captured by standard imaging, emphasizing the need for more sensitive, network-based, and molecular approaches.
Median nerve entrapment most commonly occurs at the wrist, though proximal compression due to rare fascial or myofascial variations is likely underrecognized. Fascial tunnels may persist during development or result from incomplete remodeling, creating confined spaces that predispose neurovascular structures to compression. Concurrent entrapment of both neural and vascular structures within the arm is particularly uncommon and may produce overlapping neuropathic and ischemic symptoms. We report a rare brachial myofascial tunnel identified at the junction of the middle and distal thirds of the arm. The tunnel enclosed both the median nerve and brachial artery over a 9.5 cm course extending to the cubital fossa. It possessed a thick fascial roof attached medially to the brachialis muscle and laterally to the medial intermuscular septum. Within the tunnel, the median nerve remained medial to the brachial artery, received a communicating branch from the musculocutaneous nerve, and demonstrated adhesions to the brachial artery and adjacent musculature, suggesting potential compressive interaction. Distally, the tunnel continued as a thin fascial band surrounding only the median nerve, while the brachial artery resumed its typical course. This prolonged shared neurovascular course within a confined tunnel represents a potential site of dual entrapment, with possible manifestations including proximal median neuropathy, exertional arm pain, or distal ischemic symptoms. Recognition of such anatomical variations is important for surgeons, anatomists, and clinicians, as unrecognized configurations may contribute to diagnostic uncertainty and increase the risk of iatrogenic injury during upper extremity procedures.
Background The mandible represents a practical skeletal element for sex estimation in forensic anthropological casework, by virtue of its preservation potential and measurable sexual dimorphism, particularly when primary diagnostic elements are absent. Materials and Methods A total of 260 adult skeletal specimens (130 males, 130 females) were obtained from the Unit of Human Bone Warehouse for Research, Khon Kaen University, Thailand. Seven mandibular measurements were extracted digitally from structured light 3D surface scans using standardized landmark definitions and randomly allocated into a training set (n = 200) and an independent holdout test set (n = 60). Three machine learning classifiers were evaluated: Support Vector Machine (SVM), Random Forest (RF), and Neural Network (NN), trained using 10-fold stratified cross-validation and assessed using classification accuracy (CA), F1-score, precision, recall, Matthews Correlation Coefficient (MCC), and area under the receiver operating characteristic curve (AUC). Results All seven measurements demonstrated statistically significant sexual dimorphism (p < 0.01), with bigonal width, bicondylar breadth, and bicoronoid breadth exhibiting the greatest discriminatory capacity. During cross-validation, RF achieved the highest CA (81.5%, MCC = 0.630), while SVM demonstrated the highest AUC (0.860). Upon independent validation, NN achieved the highest overall performance (CA = 86.7%, AUC = 0.938), with all three models maintaining or exceeding training set performance, suggesting preliminary evidence of generalizability with no apparent overfitting observed. Conclusion The trained models provide deployable sex estimation tools for Northeastern Thai skeletal material, contributing population-specific reference data and a multi-algorithm machine learning framework to forensic anthropological practice.
Background Sphenoid sinus pathology (e.g., sinusitis, mucocele, fungus balls, benign and malignant lesions, etc.) is common and frequently overlooked, creating a danger of inevitable complications, considering the sphenoid sinus close relations with surrounding structures. Understanding anatomical variability of this anatomical structure is crucial for proper evaluation of the sphenoid sinus pathology and development of the treatment plan. Methods This observational cross-sectional study conducted in Ukrainian population on 124 CT studies of the head of healthy subjects aged from 17 to 86 years. The following linear parameters of the sphenoid sinuses were measured separately for the right and left sinuses: height, width, and length. These parameters were compared for the right and left sphenoid sinuses in entire sample as well as for male and female groups. Pneumatization types of the sphenoid sinuses were documented and proportions were assessed. Relations with age were assessed with regression analysis and correlation coefficient. Results Statistically significant differences were identified for the right and left sphenoid sinus length, and height, and were slightly greater in males compared to females, and were found to decrease with age. The most common pneumatization type was postsellar (60.5%), seconded by presellar (16.1%) and sellar (15.3%). Conclusion The study provides new data about the anatomic variability of parameters of height, length, and width of sphenoid sinus in the Ukrainian population. Statistically significant differences in sphenoid sinus parameters between males and females were identified. The sphenoid sinus parameters can be predicted by age with statistical significance for the right sphenoid sinus.
Background: Lumbar spine morphometry varies across populations and can influence clinical and surgical outcomes. Classical morphometric indices, while informative, may not fully capture subtle anatomical variations between individuals. Objective: This study aimed to document extended Computed Tomography (CT)-derived morphometric indices of the lumbar spine in a Nigerian adult population, providing a refined assessment of structural differences between degenerative and non-pathologic (control) conditions. Methods: This retrospective case-control study included 61 participants (37 control, 24 degenerative). Lumbar CT images (<= 1 mm, 120 kVp) were analyzed using RadiAnt (R) and Vitrea. Vertebral, pedicle, and foraminal measurements were used to derive extended CT-derived morphometric indices: Vertebral Strength Index (VSI), Vertebral Shape Ratio (VSR), Pedicle Safety Angle Index (PSAI), and Pedicle-Foraminal Occupancy Index (PFOI). Group differences were assessed using independent t-tests and paired t-tests for the bilateral comparisons in IBM SPSS version 25.0 Statistics (p G 0.05). Results: Degenerative participants (58.3 +/- 9.1 years) were significantly older than controls (42.6 +/- 8.4 years; p G 0.001). Cross-sectional area (CSA) decreased at L1 (p G 0.001) but increased at L4 (p = 0.013-0.021). Extended CT-derived morphometric indices showed significant differences across multiple levels, with lower VSR and altered VSI, PSAI, and PFOI in degeneration (p G 0.001-0.043). Conclusion: Extended CT-derived morphometric indices provide a refined and practical approach to characterize spinal structural differences between control and degenerative cohorts. These extended indices can serve as useful quantitative tools for assessing degenerative spinal changes in both clinical and research settings, complement classical morphometric indices, and may provide valuable guidance for surgical planning.
Background: The superior articular facets (SAFs) of the axis vertebra (C2) are critical to atlantoaxial stability and cervical spine biomechanics. Variation in SAF angulation may influence joint congruency, load distribution, and surgical corridor orientation, with direct implications for imaging interpretation and operative planning. Population-specific morphometric data from South African osteological samples remain limited, constraining translational application. Methods: A cross-sectional osteological study was conducted on 200 adult axis vertebrae from the Raymond A. Dart Collection, South Africa. Bilateral SAF angulation was quantified using standardised digital image analysis. Specimens were stratified by age group, biological sex, and population affinity. Statistical analyses assessed bilateral asymmetry and between-group differences, with significance (p < 0.05). Results: Mean SAF angulation measured 26.13 degrees on the right and 25.98 degrees on the left, demonstrating minimal bilateral asymmetry (p = 0.679). No significant differences were observed across age groups (right: p = 0.675; left: p = 0.239) or biological sex (right: p = 0.400; left: p = 0.154). An overall association with population affinity was identified (p = 0.027; p = 0.008); however, side-specific comparisons were not significant (right: p = 0.468; left: p = 0.298). Variability within subgroups was low. Conclusion: SAF angulation demonstrates relative morphological consistency across demographic subgroups in this South African sample. Although population affinity showed an overall association, this was not consistently observed in side-specific analyses. These findings provide clinically relevant, population-specific reference values that may support preoperative planning, implant trajectory considerations, and radiological assessment. Further work integrating 3D imaging and biomechanical modelling is required to strengthen translational applicability.
