Clinical Anatomy最新文献

This research sought to examine the prevalence and severity of hyperostosis frontalis interna (HFI) in the Chicagoland anatomical body donor population. The study further aimed to elucidate potential demographic risk factors for HFI, including sex, age at death, and structural vulnerability index (SVI), as well as any common comorbidities, as gleaned from death certificates. HFI is an irregular bony overgrowth of the endocranial surface of the frontal bone. It is most often observed in postmenopausal women or in individuals with growth hormone disorders. This work investigated the distribution of HFI in a predominantly geriatric anatomical body donor population (n_total = 235, n_female = 127 n_male = 108; 19-104 years), using a macroscopic classification system that considers both the morphological appearance and the size of the affected area. Relationships between HFI and variables of interest were assessed through various non-parametric statistical tests and binomial logistic regression. While HFI was not associated with age-at-death or SVI, results indicate that there were significant sex differences in both HFI prevalence and severity. Females demonstrated higher rates of HFI across all severity types, whereas in males, HFI lesions were much less common and mostly limited to the earliest stages of disease progression. HFI was also associated with neoplasms as a cause of death. Among cancer deaths, individuals with hormone-sensitive cancers had a higher prevalence of HFI, but this difference was not statistically significant. While the causal pathways of these relationships remain unclear, the association with cancer may potentially explain the reportedly higher HFI prevalence rates in modern compared to past populations. Moreover, this research has bioarcheological and forensic implications as HFI is sometimes used to infer age and sex, given its association with older-aged females.

Plantar melanomas present unique diagnostic and surgical challenges owing to substantial regional variations in skin thickness. Although the Breslow thickness remains the primary criterion for staging and surgical excision, its application on plantar melanoma is complicated by the inherent thickness of the glabrous plantar epidermis, which may lead to tumor depth overestimation. Accurate assessment of plantar skin thickness is essential for optimizing staging accuracy and refining surgical margins. This study aimed to investigate plantar epidermal, dermal, and total skin thicknesses at 14 anatomical locations using high-frequency ultrasonography (HFUS) and histological analysis. A total of 35 ft (27 from cadavers and eight from patients) were examined. Mean total skin thickness was 1.71 ± 0.31 mm, although mean epidermal thickness was 0.55 ± 0.12 mm and mean dermal thickness was 1.16 ± 0.27 mm. Significant regional variations were observed (p < 0.05), with the heel (S11) exhibiting the greatest thickness (2.19 ± 0.29 mm) and the medial arch (S4) the least (1.41 ± 0.26 mm). The results also included thickness ranking in order of the heel, forefoot, lateral arch, and medial arch. These findings suggest that plantar skin thickness correlates with mechanical stress distribution, with weight-bearing regions exhibiting greater epidermal and dermal thicknesses. By providing a comprehensive dataset of site-specific plantar skin thicknesses, this study enhances the precision of ultrasonographic melanoma assessment, refines tumor staging, and aids in optimizing excision margins. These findings offer clinically relevant anatomical reference points that may improve surgical decision-making, minimize unnecessary excisions, and enhance the prognosis of melanoma. Further studies should explore the correlation between ultrasonographic and histopathological measurements across diverse populations to strengthen their clinical applicability.

Hyrtl's anastomosis, a transverse inter-arterial connection between the two umbilical arteries near their placental insertion, plays a vital role in maintaining hemodynamic stability in fetal circulation. Despite being a consistent finding in most term placentas, its functional role and clinical significance are underappreciated in perinatal medicine. This review explores the anatomy, physiological function, diagnostic assessment, and clinical implications of Hyrtl's anastomosis, with emphasis on its protective role in ensuring balanced placental perfusion and mitigating hemodynamic stress in compromised pregnancies. Its relevance in various obstetric conditions such as fetal growth restriction, twin pregnancies, and abnormal cord insertions is discussed. Advances in imaging and the role of placental pathology in evaluating Hyrtl's anastomosis are also highlighted. Hyrtl's anastomosis is a significant vascular protection in the fetoplacental circulation. Greater knowledge and targeted investigation into its presence, patency, and variability may improve our understanding of fetal adaptation mechanisms and help with risk stratification in high-risk pregnancies. Understanding this anatomical structure enhances diagnostic accuracy and informs clinical decision-making in fetal medicine.

There are no standardized guidelines for reconstructive surgery of large temporal bone defects following lateral temporal bone resection for external auditory (acoustic) meatus carcinoma. Filling the defect with well-vascularized tissue is important for large tissue defects to promote wound healing and prevent infection postoperatively. Patients with malignant tumors of the external acoustic meatus requiring lateral temporal bone resection may sometimes necessitate postoperative adjuvant chemoradiotherapy. Therefore, it is essential to facilitate wound healing and initiate adjuvant therapy promptly after surgery. Moreover, to prevent complications such as osteonecrosis after radiotherapy, filling the defect with well-vascularized tissue is particularly important. Reconstructing a large temporal bone defect using the temporalis muscle following lateral temporal bone resection requires several surgical tips based on anatomical knowledge. However, no previous reports have described these techniques in detail. In this report, we highlight that the creation of an effective temporalis muscle flap for large temporal bone defects after lateral temporal bone resection requires cutting the deep layer of the temporalis fascia and the pericranium, as well as the separation of tendinous structures within the temporalis muscle. In this report, based on the microsurgical anatomy of the temporalis muscle, we present an effective method for creating a reliable temporalis muscle flap for reconstructive surgery.

The postglenoid foramen (PGF) is a rarely reported anatomical variant of the temporal bone, with limited data on its morphology, prevalence, and clinical relevance, particularly in non-European populations. This study aimed to investigate the anatomy and frequency of foramina located on the squamous part of the temporal bone, including the PGF, and to propose a classification system based on their anatomical positions. A total of 117 human skulls (234 sides), including both dried and Thiel-embalmed specimens, were examined through gross observation, cadaveric dissection, and computed tomography (CT) in selected cases. Foramina were localized relative to the postglenoid process (PGP) and zygomatic arch, and classified accordingly. Foramina were identified in 48 skulls (41.0%) and 67 sides (28.6%), with no significant difference between left and right sides (p = 1.00). Based on anatomical location, three main types were identified: preglenoid (76.7%), postglenoid (6.8%), and supra-arcuate (16.4%). Three foramina were found to communicate with the middle cranial fossa, confirmed by CT imaging. The proposed classification provides a practical framework for describing their positional variation. These findings are of clinical importance, particularly in surgical planning and radiologic interpretation, as such foramina may serve as conduits for venous communication or infection. Further studies are warranted to explore their histological structure and developmental origins.

Meticulous determination of the time since death (TSD) is critical in certain criminal investigations. This study aimed to identify optimal markers for TSD estimation and develop a mathematical model applicable under varying conditions. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and β-Actin (ACTB) mRNA levels were analyzed in 10 human skeletal muscle samples using real-time quantitative PCR at eight time intervals (6, 12, 18, 24, 30, 36, 42, and 48 h) within 48 h postmortem at 25°C. Among the candidate markers, GAPDH demonstrated the strongest correlation with times since death. At the same time, ACTB expression remained comparatively stable across all samples and time points as identified by RefFinder (reference gene analysis tool). Mathematical equations were developed using the C_t values for GAPDH, ACTB, and ΔC_t (GAPDH-ACTB) and the cubic model gave the highest determination of coefficient while the error rates were low in the quadratic model. The findings indicate that ACTB is an optimal marker for estimating TSD within the 30 to 36-h postmortem interval, while GAPDH is more suitable for the 36 to 48-h period.

The connective tissue support of female pelvic viscera-endopelvic fascia-has been studied in fetal and immunohistochemical models to demonstrate its relationship with the autonomic nerves of the female pelvis. Due to a paucity of literature examining the gross anatomical relationships between endopelvic fascia and autonomic nerves in adult female pelvises, it remains unknown whether defects in endopelvic fascia predisposing pelvic organ prolapse and/or manipulation of endopelvic fascia during prolapse repair may be the cause of prolapse-related pelvic pain and sexual dysfunction. Through the dissection of formalin-fixed hemipelvises (n = 10) the present study aimed to map the loci of the visceral branches of the inferior hypogastric plexus and associate them with endopelvic fascia of the female pelvis. In all specimens, two gross bundles of autonomic nerves were identified within pubocervical fascia traveling caudally to innervate the clitoral crura, vestibular bulbs, and anterior vaginal wall. Moreover, a distinct bundle was found traveling within the rectovaginal septum innervating the posterior vaginal wall. Immunohistochemical staining for S100 protein confirmed the presence of nerves and ganglia within pubocervical fascia that were localized near the vaginal arteries. Additionally, our dissections revealed that the visceral branches of the inferior hypogastric plexus can be stratified to correspond to different named components of endopelvic fascia. Clinically, our results provide a robust anatomical characterization that will inform the development of surgical approaches to reduce the risk of pelvic neuropathy during vaginal prolapse surgery.

Urogenital epithelium replaces the original paramesonephric (Müllerian) epithelium in the human fetal vagina. We re-investigated this cell replacement histologically and with three-dimensional reconstructions. In the lesser pelvis, both Müllerian ducts fuse to form the uterovaginal canal. Its large caudal “head” is flanked by the locally widened Wolffian ducts. In the 9th week, the urogenital epithelium that covers the Müllerian tubercle differentiates into small, dense-staining basal cells and columnar “clear cells” apically. Mesonephric (Wolffian-duct) outlet epithelium in contact with clear cells degenerates and is replaced by clear-cell epithelium. Meanwhile, the small cells of the urogenital-sinus epithelium form a funnel that physically contacts the underlying uterovaginal head, locally breaks down its basement membrane, and establishes a bridgehead. Here, extensive cell mixing of urogenital and Müllerian cells produces a “transformational” epithelium with regressing Müllerian and healthy urogenital cells as components. After spreading throughout the vaginal epithelium, the urogenital cells near their incursion site under the Wolffian-duct outlets begin to produce the bilateral “vaginal plates.” Its cells surround the transformational epithelium as a deflated double-layered cell plate. Where the vaginal plates contact the transformational epithelium, the epithelial cell layer thickens, its surface becomes rugged, and large regressive cells become numerous. The number of regressive cells drops precipitously in the adjacent vaginal plates, implying that this band of cells functions as a “purging zone.” Once the purging process reaches the midline, the vaginal epithelium consists of urogenital cells only. Their arrangement as a deflated double-layered cell plate temporally occludes the vaginal lumen.

The microvasculature of peripheral nerve not only is important for the understanding of the development of compression syndromes, but it plays a critical role in the evolution of other nerve pathologies, including, for example, the distribution of intraneural ganglion cysts and lymphoma. We investigated the anatomical course of vessels around the human sciatic nerve and its bifurcation in eight human cadavers. Specifically, the presence of fenestrations on the epineurium and paraneurium's thickness in relation to the intraneural vessels was investigated. The sciatic, tibial, peroneal and sural nerves at the level of the bifurcation are surrounded by different layers, including the epineurium and paraneurial layers. Multiple fenestrations were observed in all membranes surrounding these nerves, which formed openings for the transfer of adipocytes and vessels from one compartment to the neighboring one. The openings were relatively large compared to the size of the vessels. In conclusion, vessels always travel through a natural opening in the paraneurial and epineurium. These vessels are important connections between the extrinsic and intrinsic nerve vasculature. In addition, the fenestration provides an important anatomical explanation for the possibility of transfer of anesthetic agents or different nerve pathologies, including intraneural ganglion cyst and tumors.

In 1922, Lewis published a study of in vitro plasma clot culture of vascular endothelium. In the 1950-1960s, the use of electron microscopy allowed us to demonstrate the presence in endothelial cells of specific organelles, including plasmalemmal vesicles and Weibel-Palade bodies, and the existence of structural heterogeneity. In 1980, Folkman and Haudenschild demonstrated that capillary endothelial cells can organize themselves in vitro in three-dimensional branching tubular networks. In 1983, Montesano and coworkers demonstrated that when a monolayer of microvascular endothelial cells on the surface of a collagen gel is covered with a second layer of collagen, it reorganizes within a few days into a network of branching and anastomosing tubules.