Anatomical study of jugular foramen in the neck / Estudo anatômico do forame jugular no pescoço

Abstract Introduction The anatomical complexity of the jugular foramen makes surgical procedures in this region delicate and difficult. Due to the advances in surgical techniques, approaches to the jugular foramen became more frequent, requiring improvement of the knowledge of this region anatomy. Objective To study the anatomy of the jugular foramen, internal jugular vein and glossopharyngeal, vagus and accessory nerves, and to identify the anatomical relationships among these structures in the jugular foramen region and lateral-pharyngeal space. Methods A total of 60 sides of 30 non-embalmed cadavers were examined few hours after death. The diameters of the jugular foramen and its anatomical relationships were analyzed. Results The diameters of the jugular foramen and internal jugular vein were greater on the right side in most studied specimens. The inferior petrosal sinus ended in the internal jugular vein up to 40 mm below the jugular foramen; in 5% of cases. The glossopharyngeal nerve exhibited an intimate anatomical relationship with the styloglossus muscle after exiting the skull, and the vagal nerve had a similar relationship with the hypoglossal nerve. The accessory nerve passed around the internal jugular vein via its anterior wall in 71.7% of cadavers. Conclusion Anatomical variations were found in the dimensions of the jugular foramen and the internal jugular vein, which were larger in size on the right side of most studied bodies; variations also occurred in the trajectory and anatomical relationships of the nerves. The petrosal sinus can join the internal jugular vein below the foramen.

Resumo Introdução A complexidade anatômica do forame jugular torna a realização de procedimentos cirúrgicos nessa região delicada e difícil. Devido aos avanços obtidos nas técnicas cirúrgicas, as abordagens do forame jugular têm sido feitas com maior frequência, o que requer uma melhoria correspondente no conhecimento de sua anatomia. Objetivo Estudar a anatomia do forame jugular, da veia jugular interna e dos nervos glossofaríngeo, vago e acessório, assim como as relações anatômicas entre estas estruturas na região do forame jugular e no espaço parafaríngeo. Método Foram examinados 60 lados de 30 cadáveres frescos algumas horas após a morte. Os diâmetros e suas relações anatômicas foram analisados. Resultados Os diâmetros do forame jugular e da veia jugular interna foram maiores no lado direito na maioria dos espécimes estudados. O seio petroso inferior terminava na veia jugular interna até 40 mm abaixo do forame jugular, em 5% dos casos. O nervo glossofaríngeo exibiu uma relação íntima anatômica com o músculo estiloglosso após a sua saída do crânio e o nervo vago exibiu uma relação semelhante com o nervo hipoglosso. O nervo acessório passou em torno da veia jugular interna via sua parede anterior em 71,7% dos cadáveres. Conclusão Foram encontradas variações anatômicas nas dimensões do forame jugular e da veia jugular interna, que apresentaram tamanhos maiores à direita na maioria dos espécimes estudados; variações também ocorreram na trajetória e nas relações anatômicas dos nervos. O seio petroso pode se unir à veia jugular interna abaixo do forame.

Anatomical study of jugular foramen in the neck.

INTRODUCTION: The anatomical complexity of the jugular foramen makes surgical procedures in this region delicate and difficult. Due to the advances in surgical techniques, approaches to the jugular foramen became more frequent, requiring improvement of the knowledge of this region anatomy. OBJECTIVE: To study the anatomy of the jugular foramen, internal jugular vein and glossopharyngeal, vagus and accessory nerves, and to identify the anatomical relationships among these structures in the jugular foramen region and lateral-pharyngeal space. METHODS: A total of 60 sides of 30 non-embalmed cadavers were examined few hours after death. The diameters of the jugular foramen and its anatomical relationships were analyzed. RESULTS: The diameters of the jugular foramen and internal jugular vein were greater on the right side in most studied specimens. The inferior petrosal sinus ended in the internal jugular vein up to 40mm below the jugular foramen; in 5% of cases. The glossopharyngeal nerve exhibited an intimate anatomical relationship with the styloglossus muscle after exiting the skull, and the vagal nerve had a similar relationship with the hypoglossal nerve. The accessory nerve passed around the internal jugular vein via its anterior wall in 71.7% of cadavers. CONCLUSION: Anatomical variations were found in the dimensions of the jugular foramen and the internal jugular vein, which were larger in size on the right side of most studied bodies; variations also occurred in the trajectory and anatomical relationships of the nerves. The petrosal sinus can join the internal jugular vein below the foramen.

Rare variation of the right internal jugular vein: a case study / Variação rara da veia jugular interna direita: um estudo de caso

This study reports on a rare variation of the right internal jugular vein (IJV) identified during routine anatomic dissection of a male cadaver. The right IJV had a tributary located parallel and medially to the IJV itself. This branch of the IJV emerged between the transverse processes of the 3rd and 4th cervical vertebrae and drained into the junction between the right internal jugular and brachiocephalic veins. The present study described a rare branch of the right IJV, which is important knowledge for surgeons, in order to prevent accidental injury and bleeding during surgical procedures

O presente estudo demonstrou uma variação rara da veia jugular interna direita (VJI), identificada durante uma dissecção de rotina de um cadáver masculino. A VJI direita apresentou uma tributária localizada paralelamente e medialmente à referida veia. Essa tributária da VJI emergiu entre os processos transversos das 3ª e 4ª vértebras cervicais e drenou para a junção entre as veias jugular interna e braquiocefálica direita. O conhecimento da variação anatômica demonstrado no presente estudo é importante para os cirurgiões, a fim de prevenir lesões acidentais e sangramento durante procedimentos cirúrgicos

Embryological and comparative description of the cephalic vein joining the external jugular vein: A case report.

The cephalic vein arises from the radial end of the dorsal venous arch. It turns around the radial border of the forearm and passes proximally along the arm to the shoulder, where it enters the axillary vein by penetrating the clavipectoral triangle. The cephalic vein is prone to vary at the antecubital fossa, where it forms numerous anastomoses. A male cadaver fixated with a 10% formalin solution was dissected during regular anatomy lessons. It was found that the cephalic vein crossed the upper third of the arm between two fasciculi of the deltoid muscle and reached the shoulder, where it passed above the acromion and crossed the posterior border of the clavicle in order to join the external jugular vein. The cephalic vein is one of the most used veins for innumerous activities, such as venipunctures and arteriovenous fistula creation. Furthermore, it is an anatomical landmark known for its consistent anatomy, as it possesses low rates of variability. Despite that, its anatomical variations are clinically and surgically significant and healthcare professionals must be aware of the variations of this vessel. We aim to report a rarely described variation of the cephalic vein and discuss its embryological, phylogenetic and clinical features.

Drenaje venoso de la cabeza y el cuello / Venous drainage of the head and neck

Introducción: El sistema venoso de la cabeza y el cuello presenta formaciones plexiformes constituidas por venas que no siguen el trayecto de las arterias. Dicho sistema venoso ha sido objeto de estudio de autores clásicos. Se describen plexos venosos craneo-cervico faciales que contribuyen a la formación del sistema principal vertebral y yugular. El conocimiento de la conformación del drenaje y de sus relaciones anatómicas es fundamental para el abordaje de los vasos venosos para la infusión de sustancias para el tratamiento de los pacientes. Metodología: Se realizó una búsqueda bibliográfica en diferentes portales de internet Google Scholar, Scielo y Pubmed utilizando el lenguaje "MeSH". Se recopilaron también textos clásicos y se realizo la lectura crítica, dividiendo los artículos en número de 30 en Primarios, Secundarios y Terciarios. Desarrollo: El plexo occipitovertebral se encuentra en la región cervical posterior. Dicho plexo se encuentra íntimamente asociado a las articulaciones occipito-vertebrales. Sus afluentes corresponden a cuatro venas raquídeas, dos a cada lado. Las mismas se evidencian al remover el arco posterior del atlas junto a las láminas del axis, emergiendo de la confluencia occipitoatloidea y atlantoaxoidea. El plexo latero-faringeo se encuentra ubicado en la región correspondiente a la fosa infra-temporal. El drenaje venoso queda dividido por los planos musculares en tres sectores plexiformes. El primero de ellos se ubica entre cara medial de la rama de la mandíbula junto al músculo temporal. El segundo, lo hace profundo a este último pero superficial al músculo pterigoideo medial. Completando el drenaje venoso con el tercer patrón plexiforme ubicado en relación intrínseca con la porción infra-temporal del ala mayor del hueso esfenoides. Al abordar la región parotido-maseterina se evidencia un grupo de venas conformado por dos masetéricas anteriores y entre tres y cinco afluentes glandulares. El tercer sector plexiforme se ubica en la cara infra-temporal del ala mayor del esfenoides situada horizontalmente, extendiéndose hasta la cresta infra-temporal; cresta ósea que separa dicha parte del esfenoides de la cara temporal vertical constituído por dos venas temporales profundas accesorias. El sistema de la vena yugular externa comprende a la vena yugular externa propiamente dicha y la vena yugular anterior, que es una de la ramas colaterales. El sistema de la vena yugular interna se conforma a partir de las venas intra-craneanas, venas del encéfalo y de los senos venosos craneales. Conclusión: El conocimiento de todo el drenaje venoso de la cabeza y el cuello es extenso y por ese motivo, pobremente estudiado. Los vasos afluentes o comunicantes de los plexos, aunque insignificantes pueden ser fundamentales en el desarrollo de patologías, ya que obstruyen el normal funcionamiento de la circulación.

Introduction: The venous system of the head and neck presents plexiform formations constituted by veins that do not follow the course of the arteries. This venous system has been studied by classical authors. Facial cranio-cervical venous plexuses are described that contribute to the formation of the vertebral and jugular main system. The knowledge of the conformation of the drainage, of its anatomical relations is fundamental for the approach of the venous vessels for the infusion of substances for the treatment of the patients. Methodology: A bibliographic search was carried out in different internet portals Google Scholar, Scielo, Pubmed using the "MeSH" language. Classical texts were also compiled and the critical reading was carried out by dividing the articles, in number of 30 in Primary, Secondary and Tertiary. Development: The occipitovertebral plexus is located in the posterior cervical region. This plexus is intimately associated with the occipito-vertebral joints. Its tributaries correspond to four spinal veins, two on each side. They are evident when the posterior arch of the atlas is removed next to the laminae of the axis, emerging from the occipitoatloid and atlantoaxial confluence. The latero-pharyngeal plexus is located in the region corresponding to the infra-temporal fossa. The venous drainage is divided by the muscular planes into three plexiform sectors. The first of these is located between the medial aspect of the branch of the jaw next to the temporal muscle. The second makes it deep to the latter but superficial to the medial pterygoid muscle. Completing the venous drainage with the third plexiform pattern located in intrinsic relation with the infra-temporal portion of the greater wing of the sphenoid bone. When addressing the parotid-maseterine region, a group of veins is evident, consisting of two anterior masterers and between three and five glandular tributaries. The third plexiform sector is located on the infra-temporal side of the greater wing of the sphenoid located horizontally, extending to the infra-temporal crest; bony crest that separates said part of the sphenoid from the vertical temporal face constituted by two accessory temporary deep veins. The external jugular vein system comprises the external jugular vein itself and the anterior jugular vein, which is one of the collateral branches. The internal jugular vein system is formed from intra-cranial veins, veins of the brain and cranial venous sinuses. Conclusion: The knowledge of all the venous drainage of the head and neck is extensive and for that reason, poorly studied. The affluent or communicating vessels of the plexuses, although insignificant, can be fundamental in the development of pathologies since they obstruct the normal functioning of the circulation.

Biometric measurements involving the terminal portion of the thoracic duct on left cervical level IV: an anatomic study.

To determine the point of entrance of the thoracic duct in the venous system, as well as to evaluate some biometric measurements concerning its terminal portion, we conducted an anatomic study on 25 non-preserved cadavers. The termination of the thoracic duct occurred on the confluence between the left internal jugular vein and the left subclavian vein in 60 % of the individuals. The average results for the biometric measurements were: distance between the end of left internal jugular vein and omohyoid muscle 31.2 ± 2.7 mm; distance between the end of thoracic duct and the left internal jugular vein 0.0 ± 0.0 mm; distance between the end of thoracic duct and the left subclavian vein 3.6 ± 1.0 mm; distance between the end of thoracic duct and the left brachiocephalic vein 10.7 ± 3.1 mm. Moreover, it was identified that the left internal jugular vein length in level IV, measured between its entrance in the left subclavian vein and the omohyoid muscle, was able to predict the termination of the thoracic duct on the junction between the left internal jugular vein and the left subclavian vein (OR = 2.99) with high accuracy (79.3 %). In addition, the left internal jugular vein length at level IV was able to predict the localization of thoracic duct termination. Thus, this finding has practical value in minimizing the risk for a potential chyle leak during or after a left-sided neck dissection.

Variations in the anatomical relationship between the common carotid artery and the internal jugular vein: an ultrasonographic study.

INTRODUCTION: The internal jugular vein locates anterior or anterolateral to the common carotid artery in two-thirds of the subjects studied by ultrasound when the head is in a rotated position. AIM: To identify variables associated with the anterior location of the internal jugular vein. METHODS: Ultrasound examinations were performed with the patients in the supine position, with the head rotated to the opposite side. The proximal third of the neck was visualized transversely with a 7.5-mHz transducer. The relationship between the vessels was described in accordance with the proportion of the artery overlapped by the vein. Univariate comparisons and a multivariate analysis of potential variables that may affect the anatomic relationships were performed. RESULTS: Seventy-eight patients were included, 44 of whom were men. The patients' ages ranged from 17 to 90 years (median 64.0, interquartile range 41-73). The right and left sides were studied 75 and 73 times, respectively. The vein was located lateral to the artery in 24.3% (95%CI= 17.4-32.2) of the studies, anterolateral in 33.8% (95%CI= 26.2-41.4) and anterior in 41.9% (95%CI= 33.9-49.8). The multivariate analysis identified age group (OR= 3.7, 95% CI 2.1-6.4) and, less significantly, the left side (OR= 1.7, 95%CI= 0.8-3.5) and male gender (OR= 1.2, 95%CI= 0.6-2.7) as variables associated with the anterior position of the vein. CONCLUSIÓN: The anterior position of the internal jugular vein relative to the common carotid artery increases gradually with age. Additionally, left-sided localization and male sex further increased the probability of an anterior position.

INTRODUCCIÓN: La vena yugular interna es anterior o anterolateral a la arteria carótida común en las dos terceras partes de los sujetos estudiados sonográficamente, con la cabeza rotada. OBJETIVO: Se examinó la asociación de diferentes variables con la ubicación anterior de la vena. MÉTODOS: Las ecografías se realizaron en posición supino, con la cabeza rotada hacia el lado contrario al examinado. Se visualizó transversalmente el tercio proximal del cuello, con un transductor de 7.5 mHz. La relación entre los vasos se describió de acuerdo con la proporción de la arteria cubierta por la vena. Se hicieron comparaciones univariadas con la prueba Chi2 de Pearson y un análisis multivariado de las variables candidatas a afectar las relaciones anatómicas estudiadas. RESULTADOS: Se incluyeron 78 individuos, 44 hombres, con edad entre 17-90 años (mediana 64.0, rango= 41-73 años). Se estudió el lado derecho en 75 ocasiones y el izquierdo en 73. La vena se localizó lateral en el 24.3% (IC95% 17.4-32.2) de los vasos estudiados, anterolateral en el 33.8% (IC95%= 26.2-41.4) y anterior en el 41.9% (IC95%= 33.9-49.8). El análisis multivariado identificó: el grupo etáreo (OR= 3.7, IC95%= 2.1-6.4) y sugiere el lado izquierdo (OR= 1.7, IC95%= 0.8-3.5) y el género masculino (OR= 1.2, IC95%= 0.6-2.7), como variables asociadas con la posición anterior de la vena. CONCLUSION: La ubicación anterior de la vena yugular interna respecto a la arteria carótida común aumenta gradualmente con la edad. La localización izquierda y el género masculino pueden aumentar adicionalmente esta probabilidad.

Variations in the anatomical relationship between the common carotid artery and the internal jugular vein:: An ultrasonographic study / Variaciones de la relación anatómica de la arteria carótida común y la vena yugular interna:: Estudio ecográfico

Introduction: The internal jugular vein locates anterior or anterolateral to the common carotid artery in two-thirds of the subjects studied by ultrasound when the head is in a rotated position. Aim:To identify variables associated with the anterior location of the internal jugular vein. Methods: Ultrasound examinations were performed with the patients in the supine position, with the head rotated to the opposite side. The proximal third of the neck was visualized transversely with a 7.5-mHz transducer. The relationship between the vessels was described in accordance with the proportion of the artery overlapped by the vein. Univariate comparisons and a multivariate analysis of potential variables that may affect the anatomic relationships were performed. Results: Seventy-eight patients were included, 44 of whom were men. The patients' ages ranged from 17 to 90 years (median= 64.0, interquartile range 41-73). The right and left sides were studied 75 and 73 times, respectively. The vein was located lateral to the artery in 24.3% (95%CI= 17.4-32.2) of the studies, anterolateral in 33.8% (95%CI= 26.2-41.4) and anterior in 41.9% (95%CI 33.9-49.8). The multivariate analysis identified age group (OR= 3.7, 95%CI= 2.1-6.4) and, less significantly, the left side (OR= 1.7, 95%CI 0.8-3.5) and male gender (OR= 1.2, 95%CI= 0.6-2.7) as variables associated with the anterior position of the vein. Conclusion: The anterior position of the internal jugular vein relative to the common carotid artery increases gradually with age. Additionally, left-sided localization and male sex further increased the probability of an anterior position.

Introducción: La vena yugular interna es anterior o anterolateral a la arteria carótida común en las dos terceras partes de los sujetos estudiados sonográficamente, con la cabeza rotada. Objetivo:Se examinó la asociación de diferentes variables con la ubicación anterior de la vena. Métodos: Las ecografías se realizaron en posición supino, con la cabeza rotada hacia el lado contrario al examinado. Se visualizó transversalmente el tercio proximal del cuello, con un transductor de 7.5 mHz. La relación entre los vasos se describió de acuerdo con la proporción de la arteria cubierta por la vena. Se hicieron comparaciones univariadas con la prueba Chi2 de Pearson y un análisis multivariado de las variables candidatas a afectar las relaciones anatómicas estudiadas Resultados: Se incluyeron 78 individuos, 44 hombres, con edad entre 17-90 años (mediana 64.0, rango= 41-73 años). Se estudió el lado derecho en 75 ocasiones y el izquierdo en 73. La vena se localizó lateral en el 24.3% (IC95%= 17.4-32.2) de los vasos estudiados, anterolateral en el 33.8% (IC95%= 26.2-41.4) y anterior en el 41.9% (IC95%= 33.9-49.8). El análisis multivariado identificó: el grupo etáreo (OR= 3.7, IC95%= 2.1-6.4) y sugiere el lado izquierdo (OR= 1.7, IC95%= 0.8-3.5) y el género masculino (OR= 1.2, IC95%= 0.6-2.7), como variables asociadas con la posición anterior de la vena. Conclusión: La ubicación anterior de la vena yugular interna respecto a la arteria carótida común aumenta gradualmente con la edad. La localización izquierda y el género masculino pueden aumentar adicionalmente esta probabilidad.

Neovascularization after surgical exposure of rat external jugular vein endothelium

PURPOSE: To investigate the neovascularization after exposure of the external jugular venous endothelium in an experimental model. METHODS: The sample was composed of 60 male rats of Wistar OUT B breed provided by animal colony of the Medicine College of Juazeiro do Norte, weighing 250 to 350g, aged 90-120 days. Randomized study in OUT B Wistar rats, open, with 60 days duration. The animals were distributed into three groups of 20 specimens and were subjected to the following: Group 1: neck incision with dissection, ligation and section of the external jugular vein. Group 2: neck incision with dissection and ligation of the external jugular vein. Group 3: cervicotomy without dissection of the external jugular vein without ligation or section. The animals were sacrificed, half of them in 30 days and the other half within 60 days. The material in block harvested from the operated site were sectioned and stained for immunohistochemistry with CD34 marker. RESULTS: Neovascularization occurred with level of significance when compared group 1 to group 3 at 30 days (p=0.0076) and the same occurred at 60 days (p=0.0001) (Newman-Keuls test). CONCLUSION: The group with exposure of the venous endothelium showed a significant increase of neovascularization when compared with other groups.(AU)

A case of unilateral fenestration and duplication of the external jugular vein / Un caso de fenestración unilateral y duplicación de la vena yugular externa

The external jugular vein is increasingly being utilized as the recipient vein in head and neck free tissue transfers, and for cannulation in order to conduct diagnostic procedures or intravenous therapies. The variations in the patterns of its course, and knowledge of them, are therefore important. We report on a unique and previously non-described unilateral fenestration and duplication of the external jugular vein found during the neck dissection of a 77-year-old female cadaver. Embryological evaluation and clinical implications of the anomaly are described. Clinicians and surgeons performing neck vascular or reconstructive surgery should be aware of this variation of the external jugular vein in the hope of preventing inadvertent injury.

La vena yugular externa se está utilizando cada vez como vena receptora en la transferencias de tejidos libres de cabeza y cuello, y para canulización en procedimientos de diagnóstico o terapias intravenosas. Las variaciones en los patrones de su curso, y el conocimiento de los mismos son relevantes. Se reporta una fenestración unilateral, no descrita previamente, y la duplicación de la vena yugular externa encontrada durante la disección del cadáver de una mujer de 77 años de edad. Se hace una evaluación embriológica y las implicaciones clínicas de esta anomalía. Los médicos y cirujanos que realizan cirugía vascular o reconstructiva de cuello deben tener en cuenta esta variación de la vena yugular externa con el fin de prevenir lesiones accidentales.

The Ansa Cervicalis in Fetuses / El Asa Cervical en Fetos

The formation of ansa cervicalis (AC) is somewhat complex with both its course and location along the common carotid artery and internal jugular vein (IJV) varying. The aim of the study was to document the anatomy, formation and variations of AC. Forty fetuses (gestational age: 15 to 28 weeks) were obtained from the Department of Clinical Anatomy, Westville Campus, UKZN. A detailed micro-dissection of the posterior triangle of the neck and AC were completed using standard micro-dissecting instruments. Results of the formation of AC, its relationship to IJV and variations were recorded. The superior root was identified as a long willowy nerve that branched from the hypoglossal nerve, descended on the carotid sheath, anterior to the common carotid artery and IJV in 70 % and posterior to IJV in 30 % of the specimens. The inferior root of AC originated from the ventral rami of C2-C3 in 26%; ventral ramus of C3 in 58% and ventral ramus of C2 in 16%. Variations: a) Formation: (i) Dual formation of AC: The Hypoglossal nerve formed separate loops with the ventral rami of C2 and C3 (3%); (ii) "W" shaped appearance of AC above the superior belly of omohyoid (1%); (iii) A "vago-cervical complex" 3%; b) Origin and course: The superior root of AC received a contribution from the hypoglossal nerve, a short distance later it formed a loop around the IJV to ascend to the ventral ramus of C2 as the inferior root. The precise understanding of the anatomy of AC together with variations may assist anesthetists and surgeons to accurately identify the vascular and neural relations during surgical procedures.

La formación del asa cervical (AC) compleja, tanto en su curso como en ubicación, pueden variar a lo largo de la arteria carótida común y de la vena yugular interna (VYI). El objetivo del estudio fue determinar la anatomía, formación y variaciones del AC en fetos humanos. Cuarenta fetos (edad gestacional: 15 a 28 semanas) fueron obtenidos desde el Departamento de Anatomía Clínica, Westville Campus, UKZN. En cada muestra se realizó una detallada microdisección del triángulo posterior del cuello y del AC utilizando instrumental de microdisección estándar. Fueron registrados los resultados de la formación del AC, su relación con VYI y sus variaciones. La raíz superior fue identificada como un nervio largo y delgado que se ramificaba desde el nervio hipogloso, descendía por la vaina carotídea, anterior a la a. carótida común y la VYI en el 70% de los casos, y posterior a la VYI el 30%. La raíz inferior del AC se originaba desde los ramos ventrales de C2-C3 en el 26% de los casos; desde el ramo ventral de C3 en el 58% y desde el ramo ventral de C2 en 16% de los casos. Se observaron variaciones de formación: (i) dual del AC: el nervio hipogloso formó asas separadas con los ramos ventrales de C2 y C3 (3%), (ii) forma aparente de "W" sobre el vientre superior del m. omohioideo (1%) y (iii) un "complejo vago-cervical" (3%), y variaciones de origen y curso: la raíz superior del AC recibió una contribución del nervio hipogloso, y a corta distancia formó un bucle alrededor de la VYI para ascender al ramo ventral de C2 como una raíz inferior. El conocimiento preciso de la anatomía del AC junto con variaciones pueden ayudar a identificar con precisión las relaciones vasculares y neuronales durante los procedimientos quirúrgicos a anestesistas y cirujanos.

Two rare anatomical variations of external jugular vein: an embryological overview / Dos raras variaciones anatómicas de la vena yugular externa: una visión embriológica

Human anatomy is an ocean of unending variations and its mysteries are being unravelled since ages. Knowledge of variations in the superficial veins of head and neck is essential to carry out successful surgical procedures. During routine dissection of head and neck of two middle aged male cadavers, in the Department of Anatomy, Calcutta National Medical College, Kolkata, India, we came out with some interesting venous architecture. The retromandibular vein on the left side of both the cadavers was found to be undivided and joined with the facial vein in the neck at an acute angle to form a common venous trunk at variable distances from the angle of the mandible. That trunk ultimately drained into the left subclavian vein. This might be the result of disappearance of the cephalic part of the external jugular vein and formation of an additional communication between common facial vein and the external jugular vein in foetal life. In one case, we also came across an extra transverse communication between that common trunk and the internal jugular vein. A detail of those cases with embryological explanation is attempted...

La anatomía humana tiene un sin fin de variaciones y sus misterios se han develado desde el inicio de los tiempos. El conocimiento de las variaciones anatómicas de las venas superficiales de la cabeza y del cuello es fundamental para llevar a cabo con éxito los procedimientos quirúrgicos. Durante una disección de rutina de cabeza y cuello encontramos una arquitectura venosa interesante en dos cadáveres de hombres de mediana edad en el Departamento de Anatomía de la Facultad de Medicina Nacional Calcuta, Calcuta, India. En el lado izquierdo del cuello de ambos cadáveres, la vena retromandibular no se encontraba dividida, y se unía a la vena facial en un ángulo agudo, para formar un tronco venoso común a una distancia variable desde el ángulo de la mandíbula. Ese tronco finalmente drenaba en la vena subclavia izquierda. Esto podría ser el resultado de la desaparición de la parte cefálica de la vena yugular externa y la formación de una comunicación adicional entre la vena facial común y la vena yugular externa en la vida fetal. En un caso, también se encontró con una comunicación adicional transversal entre ese tronco común y la vena yugular interna. Se realiza una descripción en detalle de los casos junto a una explicación embriológica...

Unilateral variations of vessels and nerves in the neck / Variación unilateral de vasos y nervios en el cuello

Variations of vessels and nerves in the left neck side, of 65 year old male cadaver, during the routine dissections, were detected. It was observed that the linguofacial trunk originated from external carotid artery and that the ascending pharyngeal artery originated from the occipital artery. It was determined that after the laryngeopharyngeales rami originated from the superior cervical ganglion, the branch wound around the origin of the superior thyroid artery. As an additional variation, the internal jugular vein divided. The cervical ansa and the inferior belly of the omohyoid muscle passed through the parts of the vein. We think that these type of variation can entail important difficulties during radiologic and surgical procedures of the neck region. To know these anatomical variations, is important for the anatomist and surgeons.

Durante una disección de rutina, fue observada en el lado izquierdo del cuello de un cadáver de sexo masculino de 65 años de edad variaciones anatómicas vasculares y nerviosas. Se observó que el tronco linguofacial se originaba de la arteria carótida externa y que la arteria faríngea ascendente se origina en la arteria occipital. Se determinó que los ramos laringofaríngeos originadas desde el ganglio cervical superior, giraban en torno al origen de la arteria tiroidea superior. Como una variación adicional, la vena jugular interna se encontró dividida. El asa cervical y el vientre inferior del músculo omohioideo pasaban a través de las partes de la división de la vena. Creemos que este tipo de variaciones supone dificultades importantes durante procedimientos radiológicos y quirúrgicos de la región del cuello, y por tanto, es importante que los cirujanos conozcan estas variaciones.

An unusual termination of seven veins in the jugulo-subclavian junction / Inusual terminación de siete venas en la unión yugulo-subclavia

During anatomical dissection of a female Caucasian cadaver in our department, we observed an unusual termination of seven veins at the jugulo-subclavian junction. Normally, the jugulo-subclavian junction is formed by the union of the internal jugular vein and the subclavian vein, and gives rise to the brachionocephalic vein. In our case, except from these two, five additional veins, namely the cephalic vein, the transverse cervical vein, the external jugular vein, the anterior jugular vein, and the vertebral vein, were also joined at the level of the jugulo-subclavian junction, in order to form the brachionocephalic vein. Such a variation has not yet been reported in the literature.

Durante la disección anatómica de un cadáver caucásico femenino, se observó una inusual terminación de siete venas en el lugar de unión yúgulo-subclavia. Normalmente, la unión yúgulo-subclavia consiste en la unión de la vena yugular interna y la vena subclavia, que forman la vena braquiocefálica. En nuestro caso, además de estas dos venas, se observaron cinco venas adicionales, la vena cefálica, la vena cervical transversa, la vena yugular externa, la vena yugular anterior y la vena vertebral, la que también se unió en el nivel de la unión yúgulo-subclavia, a fin de formar la vena braquiocefálica. Tal variación no ha sido reportado en la literatura.

Luteal function and blood flow during intravenous infusion of prostaglandin F2α in heifers

The effect of prostaglandin F2α (PGF) infusion for 3 h into the jugular vein on progesterone concentrations was studied in 24 Holstein heifers.Plasma concentrations of PGF were assessed by assay of 13,14-dihydro-15-keto-PGF (PGFM). The 3 h of PGF infusion were used to approximate the duration of the major concentrations of PGFM in a natural pulse. During infusion of 5, 10, or 15 mg/3 h, the concentrations of PGFM greatly exceeded the peak of a natural pulse. Plasma concentrations of progesterone decreased (P < 0.05) in the three PGF-treated groups by Hour 1 (Hour 0 = beginning of infusion). Progesterone increased between Hours 1 and 2, but the increase was significant (P < 0.03) only in the 5-mg group. Concentrations decreased more gradually between Hours 2 and 6 than between Hours 0 and 1 with no differences among PGF groups. The percentage of CL area with color-Doppler signals of blood flow were elevated similarly in the three PGF-treated groups at Hours 1 to 3 and by Hour 5 decreased to below the percentage at Hour 0. In a second experiment, approximating a natural PGFM pulse by intravenous infusion of PGF at a dose of 0.7 mg/3 h did not affect plasma progesterone concentrations. Results indicatedthat intravenous infusion of PGF for 3 h decreased theprogesterone concentration when the total dose was equivalent to doses that have been shown to be completely luteolytic when given as a single systemic injection. However, intravenous infusion of a dose of PGF that approximately simulated a natural PGFM pulse did not effect progesterone concentration.

Luteal function and blood flow during intravenous infusion of prostaglandin F2α in heifers

The effect of prostaglandin F2α (PGF) infusion for 3 h into the jugular vein on progesterone concentrations was studied in 24 Holstein heifers.Plasma concentrations of PGF were assessed by assay of 13,14-dihydro-15-keto-PGF (PGFM). The 3 h of PGF infusion were used to approximate the duration of the major concentrations of PGFM in a natural pulse. During infusion of 5, 10, or 15 mg/3 h, the concentrations of PGFM greatly exceeded the peak of a natural pulse. Plasma concentrations of progesterone decreased (P < 0.05) in the three PGF-treated groups by Hour 1 (Hour 0 = beginning of infusion). Progesterone increased between Hours 1 and 2, but the increase was significant (P < 0.03) only in the 5-mg group. Concentrations decreased more gradually between Hours 2 and 6 than between Hours 0 and 1 with no differences among PGF groups. The percentage of CL area with color-Doppler signals of blood flow were elevated similarly in the three PGF-treated groups at Hours 1 to 3 and by Hour 5 decreased to below the percentage at Hour 0. In a second experiment, approximating a natural PGFM pulse by intravenous infusion of PGF at a dose of 0.7 mg/3 h did not affect plasma progesterone concentrations. Results indicatedthat intravenous infusion of PGF for 3 h decreased theprogesterone concentration when the total dose was equivalent to doses that have been shown to be completely luteolytic when given as a single systemic injection. However, intravenous infusion of a dose of PGF that approximately simulated a natural PGFM pulse did not effect progesterone concentration.(AU)

Regional differences in veins wall viscosity, compliance, energetics and damping: analysis of the pressure-diameter relationship during cyclical overloads.

BACKGROUND: The characterization of the dynamic process of veins walls is essential to understand venous functioning under normal and pathological conditions. However, little work has been done on dynamic venous properties. AIM: To characterize vein compliance (C), viscosity (eta), peak-strain (W St) and dissipated (W(D)) energy, damping (zeta), and their regional differences in order to evaluate their role in venous functioning during volume-pressure overloads. METHODS: In a mock circulation, pressure (P) and diameter (D) of different veins (anterior cava, jugular and femoral; from 7 sheep), were registered during cyclical volume-pressure pulses. From the P-D relationship, C, W(St) and zeta (at low and high P-D levels), eta and W(D) were calculated. RESULTS: For each vein there were P-dependent differences in biomechanical, energetics, and damping capability. There were regional-differences in C, eta), W(St) and W(D) (p<0.05), but not in zeta. CONCLUSION: The regional-dependent differences in dynamics and energetics, and regional-similitude in damping could be important to ensure venous functioning during acute overloads. The lower C and higher W(St) and W(D) found in back-limb veins (femoral), commonly submitted to high volume-pressure loads (i.e. during walking), could be considered relevant to ensure adequate venous system functionality and venous wall protection simultaneously.

Aspectos macroscópicos da desembocadura das veias facial, lingual e tireóidea superior, na veia jugular interna / Macroscopic aspects of the discharge of facial, lingual and superior thyroid veins into the internal jugular vein

A veia jugular interna, no seu trajeto descendente no pescoço, recebe tributárias como a veia facial, a veia lingual e a veia tireóidea superior. As veias da cabeça e do pescoço se anastomosam livremente, promovendo, com freqüência, variações anatômicas na sua distribuição, até mesmo diferenças nos antímeros de um mesmo indivíduo. Essa grande tendência das veias de sofrerem variações anatômicas nos motivou a ampliar as investigações com relação à desembocadura das veias facial, lingual e tireóidea superior na veia jugular interna, promovendo a identificação desses vasos em peças anatômicas cadavéricas utilizadas nos laboratórios de ensino de anatomia humana. Para este trabalho, foram feitas observações macroscópicas, na forma da desembocadura das veias facial, lingual e tireóidea superior, na veia jugular interna, em 37 antímeros de cabeças humanas, fixadas em formol a 10%, sendo 11 cabeças com antímeros direito e esquerdo, 9 cabeças com antímero esquerdo e 6 cabeças com antímero direito. Nossos resultados mostraram que a veia jugular interna recebe as veias tributárias facial, lingual e tireóidea superior de maneira variada, sendo 51% com desembocadura direta dessas tributárias na veia jugular interna, 38% com formação de um tronco venoso curto, denominado tíreo-línguo-facial, e em apenas 11% a formação do tronco línguo-facial.

The internal jugular vein, in its descending course at the neck, receives tributaries among which there are: the facial vein, the lingual vein and the superior thyroid vein. The veins from the head and neck anastomose freely, and this frequently causes anatomical variations in their distribution even between the two antimeres of the same individual. This great tendency of the veins of displaying anatomical variations prompted us to widen the investigations concerning the discharge of facial, lingual and superior thyroid veins at the internal jugular vein by identifying these vessels in anatomic pieces used at the teaching laboratories of human anatomy. For this paper, macroscopic observations were made by opening the facial, lingual and superior thyroid veins into the internal jugular vein in 37 antimeres of human heads fixed in 10% formol solution: 11 heads with right and left antimeres, nine with left antimere and six with right antimere. Our results showed that the internal jugular vein receives drainage from the facial, lingual and superior thyroid vein in varied ways: in 51% of the instances, these tributaries open directly into the internal jugular vein, in 38% they form a short venous trunk named thyro-lingual-facial trunk and in only 11% there is a lingual-facial trunk.

Termination of the facial vein into the external jugular vein: an anatomical variation / Terminação da veia facial na veia jugular externa: uma variação anatômica

Different patterns of variations in the venous drainage have been observed in the past. During routine dissection in our Department of Anatomy, an unusual drainage pattern of the veins of the left side of the face of a middle aged cadaver was observed. The facial vein presented a normal course from its origin up to the base of mandible, and then it crossed the base of mandible posteriorly to the facial artery. Thereafter, it joined with the anterior division of retromandibular vein to form the common facial vein, which drained into the external jugular vein directly. Sound anatomic knowledge of the above variation in facial veins is essential to the success of surgical procedures in this region.

Padrões distintos de variações na drenagem venosa já foram observados. Durante a dissecção de rotina em nosso Departamento de Anatomia, observou-se um padrão incomum de drenagem das veias do lado esquerdo da face de um cadáver de meia idade. A veia facial apresentava curso normal de sua origem até a base da mandíbula, e então atravessava a base da mandíbula posteriormente à artéria facial. A seguir, juntava-se à divisão anterior da veia retromandibular para formar a veia facial comum, que drenava diretamente para a veia jugular externa. Um bom conhecimento anatômico da variação descrita acima nas veias faciais é essencial para garantir o sucesso que procedimentos cirúrgicos nessa região.