Anatomical Description Research Articles

The history of the study of acute appendicitis from antiquity to the present day.

The author dwells in detail on the search in the medical literature of the nineteenth - twenty-first centuries for various options for describing the anatomy, physiology and pathological physiology of the appendix, as well as its acute inflammation, complicated course, the spectrum of principles of its treatment, as well as their outcomes from antiquity to the present day. At the same time, the emphasis is placed on the study of foreign literature reviews and the search for primary sources of priority works to identify historical facts described in previously unquoted works and unknown to domestic specialists, in order to familiarize domestic specialists in the history of medical science with important details of the formation of general surgery.There is a two-hundred-year period between the anatomical description of the appendix and the recognition that it is the appendix that is the focus of acute inflammatory disease in the lower right quadrant of the abdomen. This truth was not widely recognized until the publication of R. Fitz's work 120 years later. The disease of acute appendicitis has a social character and, apparently, influenced the course of history. A comparative analysis of the possibilities of treatment of acute appendicitis and their results allowed us to establish five stages in the history of the study of acute appendicitis

What happens under the flexor tendons of the fingers in dactylitis?

Tenosynovitis is one of the most frequently described inflammatory lesions in psoriatic dactylitis. The aim of the study was to assess by ultrasound the distribution of content within the synovial sheath of the finger flexor tendons in a cadaveric experimental model of tenosynovitis and to describe anatomically the elements of the space between the flexor tendons and the palmar aspect of the proximal phalanx of the fingers. Silicone was injected under ultrasound guidance into the digital flexor sheath of the index finger of a hand specimen. Ultrasound images of the distribution of the filling of the flexor synovial space with the injected material were obtained. These images were compared with images from patients with psoriatic dactylitis. The palmar regions of the hand and fingers were dissected to check the distribution of the injected silicone in the synovial cavity. Additionally, we dissected the 2nd to 5th fingers of five cadaveric hands, including the one used for the experiment. During the injection of the substance, we observed an increasing homogeneous hypoechoic band around the flexor tendons that differed from the images of patients. Dissection of the specimen showed the injected silicone distributed throughout the digital flexor sheath to the distal interphalangeal joint. In addition, we provided an illustrated anatomical description of the elements located between the flexor tendons and the palmar aspect of the proximal phalanx, the inflammation of which could simulate flexor tenosynovitis. The observations of this study may contribute to a better understanding of the anatomical structures involved in PsA dactylitis.

Mesh modeling of system geometry and anatomy phantoms for realistic GATE simulations and their inclusion in SPECT reconstruction

Objective. Monte-Carlo simulation studies have been essential for advancing various developments in single photon emission computed tomography (SPECT) imaging, such as system design and accurate image reconstruction. Among the simulation software available, Geant4 application for tomographic emission (GATE) is one of the most used simulation toolkits in nuclear medicine, which allows building systems and attenuation phantom geometries based on the combination of idealized volumes. However, these idealized volumes are inadequate for modeling free-form shape components of such geometries. Recent GATE versions alleviate these major limitations by allowing users to import triangulated surface meshes. Approach. In this study, we describe our mesh-based simulations of a next-generation multi-pinhole SPECT system dedicated to clinical brain imaging, called AdaptiSPECT-C. To simulate realistic imaging data, we incorporated in our simulation the XCAT phantom, which provides an advanced anatomical description of the human body. An additional challenge with the AdaptiSPECT-C geometry is that the default voxelized XCAT attenuation phantom was not usable in our simulation due to intersection of objects of dissimilar materials caused by overlap of the air containing regions of the XCAT beyond the surface of the phantom and the components of the imaging system. Main results. We validated our mesh-based modeling against the one constructed by idealized volumes for a simplified single vertex configuration of AdaptiSPECT-C through simulated projection data of 123I-activity distributions. We resolved the overlap conflict by creating and incorporating a mesh-based attenuation phantom following a volume hierarchy. We then evaluated our reconstructions with attenuation and scatter correction for projections obtained from simulation consisting of mesh-based modeling of the system and the attenuation phantom for brain imaging. Our approach demonstrated similar performance as the reference scheme simulated in air for uniform and clinical-like 123I-IMP brain perfusion source distributions. Significance. This work enables the simulation of complex SPECT acquisitions and reconstructions for emulating realistic imaging data close to those of actual patients.

Anatomical Description and Literature Review of the Endoscopic Endonasal Transclival Transodontoid Approach Combined with Endoscopic Transoral Decompression to the Anterior Craniovertebral Junction: A New Strategy

To describe and evaluate the steps required to perform a combined endoscopic endonasal/transoral transclival transodontoid approach for anterior decompression of the craniovertebral junction. The endoscopic endonasal transclival transodontoid approach combined with endoscopic transoral decompression was performed on 4 cadaveric specimens. Evaluation of this combined technique; a review of the literature; and the nuances, advantages, and pitfalls are reported. Adequate wide anterior decompression was achieved in all specimens. This combined approach allowed the preservation of the anterior arch of C1 without injuring the eustachian tube anatomy and avoiding internal carotid artery manipulation. Mastery of both techniques allows for a safe and comfortable surgical corridor. The transoral and transnasal approaches should not be considered as either/or techniques, but rather as a complement to each other. However, as with all new or developing techniques, there is a steep learning curve, which requires ample training in the skull base laboratory.

Anatomical Description of Rhinoceros Iguana (Cyclura cornuta cornuta) Head by Computed Tomography, Magnetic Resonance Imaging and Gross-Sections.

In this paper, we attempted to elaborate on an atlas of the head of the rhinoceros iguana, applying modern imaging techniques such as CT and MRI. Furthermore, by combining the images acquired through these techniques with macroscopic anatomical sections, we obtained an adequate description of the relevant structures that form the head of this species. This anatomical information could provide a valuable diagnostic tool for the clinical evaluation of different pathological processes in iguanas such as abscesses and osteodystrophy secondary to nutrient imbalances, skull malformations, fractures, and neoplasia.

Anatomical Basis for the Lower Eyelid Rejuvenation.

The tear trough, hollow concavity of the lower eyelid, is one of the recognizable signs of facial aging. Anatomical description is essential in improving tear through deformity for facial rejuvenation. Fifty cadaver were microdissected. Fat pad types, fat herniation and the fibrous support system of lower lid were investigated. The areas of the fat compartments were compared using photogrammetry method and ImageJ software. Lower lids develop palpebral bags as a result of herniation of orbital fat against a weak orbital septum in all cases (%100). The attachment of the arcus marginalis at the orbital edge is a large contributor to the middle-aged appearance of the midface in all cases (100%). The most common type is Type 1 (36%). In this type, three distinct fat pads were diverged by arcuate expansion at lateral, fascia of the inferior oblique muscle at medial, as central, medial and lateral. Type 2 specimens (20%) were observed with two fat pads. Double convexity contour is in Type 3 cases (%44). It is determined that the medial fat pads are located in larger areas. Also, herniation is particularly evident in the medial and mediocentral fat pads. Analysis of the lower lid morphology enables surgeons to apply safe and effective procedures. The inferior oblique muscle and arcuate expansion structures should be supported and not be damaged during surgical interventions. Surgeons should focus mainly on the anatomical data obtained, and in this sense, surgeons apply them during aesthetic and reconstructive procedures of the lower eyelids. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Morphobiometry of the scleral ossicle rings in Chelonia mydas sea turtles.

Scleral ossicle rings of reptiles have endoskeletal functions that are not completely understood. Moreover, descriptive reports on the anatomy of those rings are scarce. We tried to make an anatomical description that could contribute to a better understanding of their functions. We quantified, histologically characterized and evaluated the morphobiometry of the scleral ossicles, and measured the aditus orbitae of 25 sea turtle (Chelonia mydas) heads. The aditus orbitae represented about one-third of the total head length and the mean area of the internal opening of each ring was up to 8.37% of the aditus orbitae area. The mean internal diameter of the rings (6.32 mm) was characteristic of scotopic species and the most frequent number of ossicles per ring varied between 11 and 12. Two new classifications were proposed for the ossicle types: plus-Verzahnung (+V) and minus-Verzahnung (-V). The bone tissue revealed a lamellar arrangement typical of compact and resistant bones. The obtained data may be used to support and expand the understanding of functions, animal activity patterns, distinctions between taxa and taphonomic interpretations.

Changing the paradigm of research.

Changing the paradigm of research.

Hybrid Fluorescence and Frequency-Domain Photoacoustic Microscopy for Imaging Development of Parhyale hawaiensis Embryos

Parhyale hawaiensis is a marine crustacean which has emerged as a powerful model organism to study molecular and cellular mechanisms linked to embryonic development and regenerative processes. Recently, several fluorescence-based optical microscopy techniques have been employed for the study of Parhyale to obtain anatomical descriptions, analyze gene expression patterns and reconstruct cell lineages. Aiming at the expansion of the imaging repertoire for this emerging model organism, we introduce a low-cost hybrid diagnostic system which integrates confocal fluorescence and frequency domain photoacoustic (FDPA) microscopy modalities, concurrently capturing both the radiative and radiationless relaxations of molecules following their excitation by an intensity-modulated laser source. We initially characterize the hybrid microscope in terms of PA signal generation efficiency and lateral spatial resolution, and subsequently evaluate its capabilities for the in vivo imaging of unlabelled and fluorescently labelled Parhyale embryos found at different stages of development. The recorded hybrid images have revealed a remarkable contrast complementarity between the integrated imaging modes, providing valuable information regarding cells’ structure, nuclei location, cellular membranes and yolk distribution. Our findings may pave the way for the broader adoption of inexpensive hybrid optical and PA microscopy methods in developmental biology, significantly upgrading the capabilities of the currently used technologies.

Descriptive Anatomical Variant of The Superficial Temporal Artery in Temporoparietal Fascia Flap in Microtia Reconstruction

Introduction: Single-stage microtia auricular reconstruction is becoming more relevant. The determining factor is a temporoparietal fascia flap (TPF) with both branches of the superficial temporal artery (STA). There are not many studies regarding vascular branching and their relation with the frontal branch of the facial nerve, hence our study Materials and Methods: Anatomical study on TPF flap harvested during single-stage endoscopic assisted microtia auricular reconstruction from May 2018 to July 2021. Flaps were observed under microscope. Variables (vascular size, number of frontal/parietal branches, distance from branching location to estimated external ear canal, distance from frontal artery to projected course of facial nerve’s frontal branch etc.) and demographic information were obtained Results: Fifty-five flaps from 54 patients were included into the study. 50/55 (90,9%) had parietal branch and 55/55 (100%) had frontal branch with mean diameter of 0.98 and 0.91 mm respectively. Regarding frontal branch, 1.8%, 25.5%, 50.9%, 16.35, 5.45% had 0-4 traverse frontal branch(es), respectively. The mean distance from the frontal artery to the estimated course of the facial nerve’s frontal branch was 10.56 mm. 5/16 flaps that missing or small parietal/frontal branch (<0.5mm) had small necrosis while only 2/39 remaining flaps do, which is statically significant (p=0.018). All said necrosis were successfully repair with local flap, and no framework was removed. One case had nerve damage during flap harvest Conclusion: Detail anatomical description of the STA allow arterial-based flap designing and harvest, which in turn tremendously improve surgical success rate by diminishing flap necrosis and nerve damages.

Anatomical description of the perforating cutaneous nerve.

The perforating cutaneous nerve/perforating nerve of the sacrotuberous ligament is rarely observed. It usually arises from the posterior division of the sacral plexus or the pudendal nerve and perforates the sacrotuberous ligament. The anatomy of this nerve and its variants is poorly described in the literature, but there are data indicating its role in pudendal neuralgia. Herein, we present an anatomical study of six formalin-fixed cadavers with descriptions of the topography of spinal nerves S2-S4, the pudendal bundle, the perforating cutaneous nerve and the sacrotuberous ligament. We found three perforating cutaneous nerves and described each of them in detail, with measurements of length and width, and point of perforation of the sacrotuberous ligament. We distinguished three types of perforating cutaneous nerve on the basis of our findings and previous publications; two of the three types were observed in our study.

First jejunal vein, jejunal trunk, and pancreatico-duodenectomy: resolving the literature conundrum.

A detailed knowledge of the surgical anatomy of tributaries of the superior mesenteric vein, especially proximal jejunal venous anatomy (first jejunal vein and jejunal trunk), is a key prerequisite for performing a safe pancreatico-duodenectomy. However, the available literature on the anatomical course and surgical relevance of these vessels is scarce, the nomenclature across the articles is heterogeneous, and the resulting evidence is confusing to interpret. Standardized terminology and an in-depth review of these vessels with regard to their course, termination, vascular relations, and variations will help the surgeons in planning and performing this complex surgery safely, especially when a venous resection and reconstruction is planned in cases of borderline resectable pancreatic cancer. A uniform nomenclature and a unifying classification are proposed in this review for these two tributaries to help resolve the literature conundrum. This standardized terminology and anatomical description will assist the radiologists in reporting pancreatic protocol-computed tomography scans and surgeons in selecting the appropriate steps for the different anatomical orientations of these tributaries for the performance of safe pancreatic surgery. This will also help future researchers communicate in well-defined terms in reference to these tributaries so as to avoid confusion in future studies.

A neuromuscular human body model for lumbar injury risk analysis in a vibration loading environment

Background and objectiveLong-term intensive exposure to whole-body vibration substantially increases the risk of low back pain and degenerative diseases in special occupational groups, like motor vehicle drivers, military vehicle occupants, aircraft pilots, etc. This study aims to establish and validate a neuromuscular human body model focusing on improvement of the detailed description of anatomic structures and neural reflex control, for lumbar injury analysis in vibration loading environments. MethodsA whole-body musculoskeletal in Opensim codes was first improved by including a detailed anatomic description of spinal ligaments, non-linear intervertebral disc, and lumbar facet joints, and coupling a proprioceptive feedback closed-loop control strategy with GTOs and muscle spindles modeling in Python codes. Then, the established neuromuscular model was multi-levelly validated from sub-segments to the whole model, from regular movements to dynamic responses to vibration loadings. Finally, the neuromuscular model was combined with a dynamic model of an armored vehicle to analyze occupant lumbar injury risk in vibration loadings due to different road conditions and traveling velocities. ResultBased on a series of biomechanical indexes, including lumbar joint rotation angles, the lumbar intervertebral pressures, the displacement of the lumbar segments, and the lumbar muscle activities, the validation results show that the present neuromuscular model is available and feasible in predicting lumbar biomechanical responses in normal daily movement and vibration loading environments. Furthermore, the combined analysis with the armored vehicle model predicted similar lumbar injury risk to the experimental or epidemiologic studies. The preliminary analysis results also showed that road types and travelling velocities have substantial combined effects on lumbar muscle activities, and indicated that intervertebral joint pressure and muscle activity indexes can need to be jointly considered for lumbar injury risk evaluation. ConclusionIn conclusion, the established neuromuscular model is an effective tool to evaluate vibration loading effects on injury risk of the human body and assist vehicle design vibration comfort by directly concerning the human body injury itself.

Anatomical Description of the Duct System of the Pancreas: A Cadaveric and Magnetic Resonance Cholangiopancreatography Study

Anatomical Description of the Duct System of the Pancreas: A Cadaveric and Magnetic Resonance Cholangiopancreatography Study

"Neuro-Fiber Mapping": An Original Concept of Spinal Cord Neural Network Spatial Targeting Using Live Electrostimulation Mapping to (Re-)Explore the Conus Medullaris Anatomy.

Spinal cord (SC) anatomy is often assimilated to a morphologically encapsulated neural entity, but its functional anatomy remains only partially understood. We hypothesized that it could be possible to re-explore SC neural networks by performing live electrostimulation mapping, based on "super-selective" spinal cord stimulation (SCS), originally designed as a therapeutical tool to address chronic refractory pain. As a starting point, we initiated a systematic SCS lead programming approach using live electrostimulation mapping on a chronic refractory perineal pain patient, previously implanted with multicolumn SCS at the level of the conus medullaris (T12-L1). It appeared possible to (re-)explore the classical anatomy of the conus medullaris using statistical correlations of paresthesia coverage mappings, resulting from 165 different electrical configurations tested. We highlighted that sacral dermatomes were not only located more medially but also deeper than lumbar dermatomes at the level of the conus medullaris, in contrast with classical anatomical descriptions of SC somatotopical organization. As we were finally able to find a morphofunctional description of "Philippe-Gombault's triangle" in 19th-century historical textbooks of neuroanatomy, remarkably matching these conclusions, the concept of "neuro-fiber mapping" was introduced.

His bundle pacing success and electrical parameter stability regardless of three-dimensional transthoracic echocardiography lead localization.

His bundle pacing (HBP) is the most physiological form of ventricular pacing. Few prospective studies have analyzed lead localization using imaging techniques and its relationship with electrical parameters and capture patterns. The objective of this study is to examine the correlation between electrical parameters and lead localization using three-dimensional transthoracic echocardiography (3D TTE). This single-center, prospective, nonrandomized clinical research study (January 2018 to June 2020) included patients with an indication of permanent pacing, in whom 3D TTE was performed to define lead localization as supravalvular or subvalvular. A total of 92 patients were included: 56.5% of leads were supravalvular, and 43.5% were subvalvular, which resembles previous anatomic descriptions of autopsied hearts of His bundle localization within the triangle of Koch (ToK). R-wave sensing was higher when the His lead was localized subvalvular instead of supravalvular. His lead localization was not associated with HBP threshold or impedance differences, nor with the two different HBP patterns of capture, or with the ability of HBP to correct baseline BBB. The thresholds remained stable during follow-up visits, regardless of His lead localization. Higher R-wave sensing was observed during follow-up than at baseline, mainly in the subvalvular His leads. However, lead impedances in both positions decreased during follow-up. Lead localization in relation to the tricuspid valve did not influence the electrical performance of HBPs. Wide anatomical variations of the His bundle within the ToK explain our findings, reinforcing the idea that the technique for HBP should be fundamentally guided by electrophysiological and not anatomical parameters.

Clinical and anatomic description of patients with arteriovenous malformation treated with endovascular therapy in a Mexican population.

Arteriovenous malformations (AVMs) are benign congenital lesions. The estimated prevalence is 10-18 per 100,000 individuals, with an incidence rate of 1.1-1.4 per 100,000 person-year; only 12% of AVMs present symptoms during life. It is important to study different characteristics associated with AVMs because these patients require multidisciplinary treatment. A descriptive, observational, longitudinal, and retrospective study was carried out from January 15, 2016 to October 19, 2021. Convenience sampling was used on patients diagnosed with arteriovenous malformation. Sociodemographic data was obtained, such as: sex, age, site, predominant symptoms, clinical debut, type of malformation, data associated with post therapy evolution, type of embolizing agent used, associated complications, Rankin scale, and death. Data from 535 procedures was collected, we calculated an incidence of 4.4 cases per million inhabitants. Ninety procedures in 56 patients that used endovascular therapy were obtained with a female-male ratio of 0.75 and an age distribution of 35±14 (SD). A 36.3±11.5 (SD) mm diameter was registered. There was a 33% success rate for endovascular surgery. The multidisciplinary treatment of AVMs is made up of three pillar techniques: microsurgical resection, embolization, and radio-neurosurgery. It is extremely important to make an appropriate decision, with an emphasis on achieving better functional outcomes for the patient. Although neurological endovascular therapy was initially used as an adjuvant treatment for neurosurgery and radio-neurosurgery, it has been used more and more frequently as the first line of treatment.

Anatomical Description of Loggerhead Turtle (Caretta caretta) and Green Iguana (Iguana iguana) Skull by Three-Dimensional Computed Tomography Reconstruction and Maximum Intensity Projection Images.

The growing interest in reptiles has posed a challenge to veterinary clinicians due to the lack of a standardized system to perform anatomical studies similar to those used for dogs and cats. In this paper, we have attempted to describe, employing computed tomography and subsequent three-dimensional reconstructions, the normal anatomical features that comprise the skulls of two species of reptiles: the loggerhead turtle (Caretta caretta) and the green iguana (Iguana iguana). Computed tomography (CT) and subsequent image processing allowed the identification of the bony structures that comprise the head of these species. As a result, and based on previous articles, we propose the most significant anatomical differences and similarities between these species.

Neuroanatomy of the crocodylomorph Portugalosuchus azenhae from the late cretaceous of Portugal.

We present the first detailed braincase anatomical description and neuroanatomical study of Portugalosuchus azenhae, from the Cenomanian (Late Cretaceous) of Portugal. This eusuchian crocodylomorph was originally described as a putative Crocodylia and one of the oldest representatives of this clade; however, its phylogenetic position remains controversial. Based on new data obtained from high resolution Computed Tomography images (by micro-CT scan), this study aims to improve the original description of this taxon and also update the scarce neuroanatomical knowledge of Eusuchia and Crocodylia from this time interval, a key period to understand the origin and evolution of these clades. The resulting three-dimensional models from the CT data allowed a detailed description of its well-preserved neurocranium and internal cavities. Therefore, it was possible to reconstruct the cavities of the olfactory region, nasopharyngeal ducts, brain, nerves, carotid arteries, blood vessels, paratympanic sinus system and inner ear, which allowed to estimate some neurosensorial capabilities. By comparison with other crocodylomorphs, these analyses showed that Portugalosuchus, back in the Cenomanian, already displayed an olfactive acuity, sight, hearing and cognitive skills within the range of that observed in other basal eusuchians and crocodylians, including extant species. In addition, and in order to test its disputed phylogenetic position, these new anatomical data, which helped to correct and complete some of the original observations, were included in one of the most recent morphology-based phylogenies. The position of Portugalosuchus differs slightly from the original publication since it is now located as a "thoracosaurid" within Gavialoidea, but still as a crocodylian. Despite all this, to better contrast these results, additional phylogenetic analyses including this new morphological character coding together with DNA data should be performed.

Comparative Morphological and Computed Tomographical Measurements of the Orbit in Cattle and Pig Eyes

Understanding species intraocular parameters using computed tomography (CT) scanning is initial and crucial step in ophthalmology. There is a lack of studies that have specialized in estimating the cattle and pig eyes using CT scans. Therefore, this study aimed to describe the anatomical and computed tomography features of cattle and pig eyes and its internal structures. Animal heads that not suffer from any diseases related to the eye were disarticulated. CT scan was performed. Moreover, 10 % fixed buffered formalin Specimens were used for the anatomical description of the eye and the optic nerve in particular. The values of length, width of the lens and globe, radio density of the optic nerve, lens, the anterior chamber, the vitreous chamber, and orbital dimensions were measured. Statistically, all parameters of cattle optic nerve increased significantly than that of the pig except for radiodensity, and angle of the optic nerve. Furthermore, all intraocular parameters of cattle increased significantly than that of the pig except the radiodensity of aqueous and vitreous humor. There was no significant difference between species in the opening angle of the orbit. This study's findings represent a first step toward developing CT reference values for cattle and pigs intraocular structural assessments.