Maxillary Vein Research Articles

Computed tomographic characteristics of anatomical variations of external and internal jugular veins in dogs.

The external jugular vein (EJV) has been commonly used for clinical procedures in veterinary medicine, while the internal jugular vein (IJV) has been used mainly for research. Limited literature regarding anatomical variants in both EJV and IJV is available. The objectives of this descriptive retrospective study were to identify the number of dogs with variations of the jugular veins in canine patients undergoing CT of the head and neck and characterize these variations. Of 1000 dogs, 193 dogs (19.3%) had anatomical variations. Six types of anatomical variations were identified. The most common Type I was the absence of the linguofacial vein (72.0%, n=139), with the lingual, facial, and maxillary veins entering the EJV at a common branching point. Type II described a variable course of the EJV and IJV, which in some dogs resulted in the absence of the EJV (14.0%, n=27). Type III was a variable anastomotic loop formed by the linguofacial or maxillary vein cranial or at the junction of the EJV (4.2%, n=8). In Type IV, the EJV was either suspected to be aplastic or markedly reduced in diameter compared with the contralateral side just distal to its formation (3.6%, n=7). Type V was found in only six dogs (3.1%) with unilateral differences in the diameter of the IJV. Six of 193 dogs had a combination of more than one variation (Type VI, 3.1%). Type I was significantly observed more frequently in meso- and dolichocephalic breeds. Type II was significantly observed more frequently in brachycephalic breeds.

A Rare Combined Variation of the Fenestrated External Jugular Vein, Absent Retromandibular Vein, and Hypoplastic Internal Jugular Vein

A unique venous pattern was observed on the left side of the neck in a 70-year-old male cadaver. Variations were observed in the formation of the external jugular vein (EJV) associated with a hypoplastic internal jugular vein (IJV). The retromandibular vein did not form, and the superficial temporal vein continued as the EJV. The linguofacial and maxillary veins united and drained into the EJV, whereas the posterior auricular vein was absent. In addition, a slit-like fenestration in the EJV was present in the middle of the vein, which was 41.54 mm long. IJV of the same side was hypoplastic throughout its course in the neck, and the external diameter was 6 mm. IJV and EJV are frequently accessed for central venous pressure monitoring or intravenous infusion and are encountered during cervical lymphadenectomy. Awareness of the anatomical irregularities is critical to avert unanticipated complications.

Aspectos clínicos, ultrassonográficos e patológicos da tromboflebite iatrogênica em uma égua - relato de caso

ABSTRACT A 7-year-old quarter horse mare showed swelling of the tongue, head and neck region, dyspnea, and red urine after eight days of administration of intravenous medications by the animal's handler. The horse was referred to the University Veterinary Hospital of the Federal University of Pará and, at the clinical examination, showed apathy, edema in the head, neck, and tongue region, which was slightly cyanotic and with loss of epithelium in the dorsal region. The maxillary, linguofacial and external jugular veins were bilaterally engorged, firm to palpation and with cord-shaped appearance, with extension of the head to the entrance to the thoracic cavity. Ultrasound examination showed a thrombi with a hyperechoic and heterogeneous appearance that completely obstructed the vessel. The horse died five days after entering the Hospital and at necropsy it was observed: maxillary, linguofacial and external jugular veins bilaterally filled with firm, dark red to blackish thrombi; ulcerated areas in the final third of the esophagus and the stomach; lighter areas on the surface of the kidneys and dark areas at the corticomedullary junction. Based on clinical, ultrasonographic and necropsy findings, iatrogenic thrombophlebitis was diagnosed, associated with repeated injections of drugs administered intravenously.

The Anatomy of the Stomatognathic System in Different Skull Types in Dogs.

The anatomy of the stomatognathic system is important for both clinical evaluations and surgical approaches in all animal species. The aim of this study was to describe the innervation and vascularization of the stomatognathic system of the dog. Twelve dogs without a history of disease or cranial malformation were used: 4 brachycephalic, 4 mesocephalic, and 4 dolichocephalic. The dogs were dissected, and arteries, veins, and nerves related to the masticatory and swallowing components were identified. The distribution pattern of these structures in the 3 different skull types were observed. The entire blood supply of the stomatognathic system is derived from the external carotid artery, which originates from the common carotid artery, and terminates as it branches into the superficial temporal and maxillary arteries. The other main branches of the common carotid artery are the occipital, cranial laryngeal, ascending pharyngeal, lingual, facial, caudal auricular, and parotid arteries. Blood drainage was achieved via the external jugular vein, which originates from the union of the linguofacial and maxillary veins. Brachycephalic dogs had blood vessels with greater sinuosity (more deviations) when compared to dolichocephalic and mesocephalic dogs. The stomatognathic system innervation of brachycephalic skull dogs showed differences in the distribution of the facial nerve in the labial commissure and maxillary and mandibular regions. The cranial conformation of dogs demonstrated anatomical variations of the vascular and neural structures of the stomatognathic system. This data may be useful to improve clinical practice, surgical planning, and interpretation of clinical dysfunctions.

Do blood parasites increase immature erythrocytes and mitosis in amphibians?

Introduction: In amphibians, blood may act as a hematopoietic tissue. However, the knowledge concerning hematological features is scarce, there is not much information that allows an analysis about the possible explanations of this physiological feature. Objective: This study aimed to evaluate the relationship between immature red blood cells (RBCs) mitosis and the presence of blood parasites in amphibians. Methods: We sampled 116 amphibians (31 species) in six Colombian localities. Blood was taken by cardiac puncture or maxillary vein puncture. Smears were prepared, fixed, and Giemsa stained for microscopical analysis. The variables analyzed were the percentage of immature RBCs, mitotic cells in peripheral blood, and blood parasite infection. Data were analyzed using Wilcoxon's rank test and exact Fisher statistical tests. Results: Sixty-two individuals showed mitosis in peripheral blood, and these mitotic RBCs shared morphological features with immature RBCs. Overall, parasite prevalence was 30.1 %, distributed as follows: Trypanosoma (24.1 %), Hepatozoon-like (6 %), Dactylosoma (4.3 %), Karyolysus-like (0.9 %), and Filarioidea (2.6 %). A positive association between the percentage of immature RBCs and the presence of mitotic RBCs was found, and also between the blood parasite infection and the percentage of immature RBCs. Conclusions: In this study, we found that the presence of blood parasites, immature RBCs, and RBCs mitosis are frequent events in amphibians' peripheral blood, and our analysis suggests an association between those features. Thus, the release of immature RBCs and the mitosis of those cells in peripheral blood may be a physiological response to blood parasite infection. Further studies characterizing hematology in amphibians and wildlife, in general, are desirable.

Jugular vein venepuncture and anatomy in Australian

We describe our experiences collecting blood from Australian Rattus. We found uniform anatomy of the external jugular vein between Australian and exotic Rattus species. Understanding where the maxillary and linguofacial veins join to form the external jugular vein is critical to venepuncture. After locating this union, we consistently achieved successful venepuncture of the external jugular vein; yielding large blood volumes. All other routes of venepuncture yielded minute blood volumes or were unsuccessful. We provide recommendations for venepuncture in Australian rodents and encourage others to share their experiences; such reports facilitate sampling rarely sampled species and promote animal welfare.

Retromandibular vein position and course patterns in relation to mandible: anatomical morphologies requiring particular vigilance during sagittal split ramus osteotomy.

Major bleeding associated with sagittal split ramus osteotomy (SSRO) involves vessels such as the inferior alveolar, facial, and maxillary arteries and veins, and the retromandibular vein (RMV). The present study aimed to clarify and classify the three-dimensional variations in RMV position and course direction in relation to the mandible. Specimens comprised a total of 15 scientific cadavers, and the relationship between RMV and the mandible lateral and posterior views was observed. We identified 3 patterns on the lateral view, the mean distance between the RMV and the posterior border of the ramus was 3.9 mm at the height of the lingula. A total of five course patterns were identified on the posterior view. In no course pattern, the RMV inferior to the lingula was lateral to its position superior to the lingual. The present findings suggest that it may be possible to predict correlations with intraoperative bleeding risk. Further study is planned using contrast computed tomography in patients with jaw deformity for skeletal classification.

Reproductive outcomes in Criollo mares using semen biotechnologies

The present study was performed on 12 heads of donkey’s cadavers of both sexes for different anatomic techniques and on 20 live adult donkeys for ultrasonographic approaches of local anesthetic techniques. The aim was to achieve safe desensitization of the ear canal and tympanic membrane in addition to measuring different parameters of the structures occupying the infra-auricular parotid region. The internal auricular nerve was divided into two fine branches and constituting, at its origin, a characteristic V-shape with the caudal auricular nerve. The styloid process of auricular cartilage was an adequate landmark for ultrasonographic needle-guided anesthesia for internal auricular and auriculopalpebral nerves, whereas the great auricular nerve was easily palpated subcutaneously that showed safety and success in all cases. The auricular branch of mandibular nerve joined the auriculopalpebral branch of facial nerve. The maxillary vein was descending, partially embedded within the texture of the parotid glandular tissue. The parotid gland divided into five segments was clearly demarcated by maxillary vein tributaries with three main collecting radicles pouring into the parotid duct. The mandibular duct received about 12–15 fine radicles and supplied with a separate branch from the external carotid artery. Using the Doppler sonographic technique in donkeys for diagnosis of ear affections, evaluation of retrograde sialography to salivary glands with their blood vasculature and their indices might be helpful for the detection of different critical abnormalities, such as stenosis, thrombosis, and other vasopathological affections through measuring their resistivity and pulsatility indices.

Endogenous plasma progesterone levels in normal mares and embryo recipient mares between days 11 and 16 of gestation in a commercial breeding program

The present study was performed on 12 heads of donkey’s cadavers of both sexes for different anatomic techniques and on 20 live adult donkeys for ultrasonographic approaches of local anesthetic techniques. The aim was to achieve safe desensitization of the ear canal and tympanic membrane in addition to measuring different parameters of the structures occupying the infra-auricular parotid region. The internal auricular nerve was divided into two fine branches and constituting, at its origin, a characteristic V-shape with the caudal auricular nerve. The styloid process of auricular cartilage was an adequate landmark for ultrasonographic needle-guided anesthesia for internal auricular and auriculopalpebral nerves, whereas the great auricular nerve was easily palpated subcutaneously that showed safety and success in all cases. The auricular branch of mandibular nerve joined the auriculopalpebral branch of facial nerve. The maxillary vein was descending, partially embedded within the texture of the parotid glandular tissue. The parotid gland divided into five segments was clearly demarcated by maxillary vein tributaries with three main collecting radicles pouring into the parotid duct. The mandibular duct received about 12–15 fine radicles and supplied with a separate branch from the external carotid artery. Using the Doppler sonographic technique in donkeys for diagnosis of ear affections, evaluation of retrograde sialography to salivary glands with their blood vasculature and their indices might be helpful for the detection of different critical abnormalities, such as stenosis, thrombosis, and other vasopathological affections through measuring their resistivity and pulsatility indices.

Effect of cryoprotectant exposure on blastocyst development of vitrified immature equine oocytes

The present study was performed on 12 heads of donkey’s cadavers of both sexes for different anatomic techniques and on 20 live adult donkeys for ultrasonographic approaches of local anesthetic techniques. The aim was to achieve safe desensitization of the ear canal and tympanic membrane in addition to measuring different parameters of the structures occupying the infra-auricular parotid region. The internal auricular nerve was divided into two fine branches and constituting, at its origin, a characteristic V-shape with the caudal auricular nerve. The styloid process of auricular cartilage was an adequate landmark for ultrasonographic needle-guided anesthesia for internal auricular and auriculopalpebral nerves, whereas the great auricular nerve was easily palpated subcutaneously that showed safety and success in all cases. The auricular branch of mandibular nerve joined the auriculopalpebral branch of facial nerve. The maxillary vein was descending, partially embedded within the texture of the parotid glandular tissue. The parotid gland divided into five segments was clearly demarcated by maxillary vein tributaries with three main collecting radicles pouring into the parotid duct. The mandibular duct received about 12–15 fine radicles and supplied with a separate branch from the external carotid artery. Using the Doppler sonographic technique in donkeys for diagnosis of ear affections, evaluation of retrograde sialography to salivary glands with their blood vasculature and their indices might be helpful for the detection of different critical abnormalities, such as stenosis, thrombosis, and other vasopathological affections through measuring their resistivity and pulsatility indices.

The presence of uterine edema on day fourteen post ovulation and its effects on embryo transfer rates

The present study was performed on 12 heads of donkey’s cadavers of both sexes for different anatomic techniques and on 20 live adult donkeys for ultrasonographic approaches of local anesthetic techniques. The aim was to achieve safe desensitization of the ear canal and tympanic membrane in addition to measuring different parameters of the structures occupying the infra-auricular parotid region. The internal auricular nerve was divided into two fine branches and constituting, at its origin, a characteristic V-shape with the caudal auricular nerve. The styloid process of auricular cartilage was an adequate landmark for ultrasonographic needle-guided anesthesia for internal auricular and auriculopalpebral nerves, whereas the great auricular nerve was easily palpated subcutaneously that showed safety and success in all cases. The auricular branch of mandibular nerve joined the auriculopalpebral branch of facial nerve. The maxillary vein was descending, partially embedded within the texture of the parotid glandular tissue. The parotid gland divided into five segments was clearly demarcated by maxillary vein tributaries with three main collecting radicles pouring into the parotid duct. The mandibular duct received about 12–15 fine radicles and supplied with a separate branch from the external carotid artery. Using the Doppler sonographic technique in donkeys for diagnosis of ear affections, evaluation of retrograde sialography to salivary glands with their blood vasculature and their indices might be helpful for the detection of different critical abnormalities, such as stenosis, thrombosis, and other vasopathological affections through measuring their resistivity and pulsatility indices.

Response of the cerebral vasculature to systemic carbon monoxide administration-Regional differences and sexual dimorphism.

Previous studies about the modulation of the vasculature by CO were performed exclusively in male or sexually immature animals. Understanding the sex differences regarding systemic drug processing and pharmacodynamics is an important feature for safety assessment of drug dosing and efficacy. In this work, we used CORM-A1 as source of CO to examine the effects of this gasotransmitter on brain perfusion and the sex-dependent differences. Dynamic contrast-enhanced imaging (DCE)-based analysis was used to characterize the properties of CO in the modulation of cerebral vasculature in vivo, in adult C57BL/6 healthy mice. Perfusion of the temporal muscle, maxillary vein and in hippocampus, cortex and striatum was analysed for 108min following CORM-A1 administration of 3 or 5mg/kg. Under control conditions, brain perfusion was lower in females when compared with males. Under CO treatment, females showed a surprisingly overall reduced perfusion compared with controls (F=3.452, p=.0004), while no major alterations (or even the expected increase) were observed in males. Cortical structures were only modulated in females. A striking female-dominated vasoconstriction effect was observed in the hippocampus and striatum following administration of CO, in this mixed-sex cohort. As these two regions are implicated in episodic and procedural memory formation, CO may have a relevant impact in learning and memory.

Gross Anatomical, Radiographic and Doppler Sonographic Approach to the Infra-auricular Parotid Region in Donkey (Equus asinus)

The present study was performed on 12 heads of donkey’s cadavers of both sexes for different anatomic techniques and on 20 live adult donkeys for ultrasonographic approaches of local anesthetic techniques. The aim was to achieve safe desensitization of the ear canal and tympanic membrane in addition to measuring different parameters of the structures occupying the infra-auricular parotid region. The internal auricular nerve was divided into two fine branches and constituting, at its origin, a characteristic V-shape with the caudal auricular nerve. The styloid process of auricular cartilage was an adequate landmark for ultrasonographic needle-guided anesthesia for internal auricular and auriculopalpebral nerves, whereas the great auricular nerve was easily palpated subcutaneously that showed safety and success in all cases. The auricular branch of mandibular nerve joined the auriculopalpebral branch of facial nerve. The maxillary vein was descending, partially embedded within the texture of the parotid glandular tissue. The parotid gland divided into five segments was clearly demarcated by maxillary vein tributaries with three main collecting radicles pouring into the parotid duct. The mandibular duct received about 12–15 fine radicles and supplied with a separate branch from the external carotid artery. Using the Doppler sonographic technique in donkeys for diagnosis of ear affections, evaluation of retrograde sialography to salivary glands with their blood vasculature and their indices might be helpful for the detection of different critical abnormalities, such as stenosis, thrombosis, and other vasopathological affections through measuring their resistivity and pulsatility indices.

Course of the Maxillary Vein and its Positional Relationship With the Mandibular Ramus Require Attention During Mandibuloplasty.

The maxillary vein is associated with major hemorrhage, an intraoperative risk factor during mandibuloplasty. Our objectives in this study were to identify the anatomical course of the maxillary vein relative to the mandible, and to ascertain the relationship of its course with that of the maxillary artery. Thirteen sides of 13 cadavers in the possession of the Department of Anatomy of Tokyo Dental College were used. The maxillofacial region was first dissected, after which the upper part of the mandibular ramus was removed and the maxillary artery, maxillary vein, and pterygoid venous plexus were identified. The length of the maxillary vein and its height from the mandibular plane were then measured, and its anatomical course was recorded. The maxillary vein ran downward along the inner aspect of the temporal muscle, then from the base of the coronoid process it ran horizontally near the bone surface of the inner aspect of the mandibular ramus. After joining the inferior alveolar vein, it joined the superficial temporal vein to form the retromandibular vein. The mean length of the maxillary vein was 22.2 ± 3.2 mm. At the posterior margin of the mandibular ramus, its mean height above the mandibular plane was 34.2 ± 5.4 mm. From the posterior margin of the mandibular ramus to the lowest point of the mandibular notch, the maxillary vein was located within the areolar connective tissue directly above the periosteum adjoining the inner aspect of the mandibular ramus. In the wide area from the center of the maxillary notch to the posterior margin of the mandibular ramus, the maxillary vein runs extremely close to the periosteum on the inner aspect of the mandibular ramus, suggesting that it may pose a risk of hemorrhage in various oral surgical procedures.

Clinical anatomy of the accessory mandibular foramen: application to mandibular ramus osteotomy.

An accessory foramen around the mandibular foramen is called an accessory mandibular foramen (AMF). The clinical anatomy of the AMF has not been well described. The aim of this study was to reveal the clinical anatomy of the AMF for a better understanding of its implication during ramus surgeries. Twenty-two sides fresh-frozen cadaveric heads with a mean age of 76.2 ± 14.4years at death underwent dissection. The neurovascular bundles passing through the AMF were observed. Additionally, a hemi-face of a latex injected embalmed cadaver was dissected medially to laterally and the neurovascular bundles of the AMF investigated. A unilateral foramen, bilateral foramina, and absence of foramina were found in 45.4%, 18.2%, and 36.4%, respectively. The origin of the neurovascular bundle entering the AMF was a branch of the maxillary artery in 20% and a tributary of the inferior alveolar vein in 80%. In the latex embalmed cadaver, the AMF was found to contain a branch from the maxillary artery and a tributary of the maxillary vein. Given the practical meaning of the specific AMF located in the operative field of the ramus osteotomy, we suggest these be named "foramina for ramus osteotomy."

Pilot study of trans-oral ultrasonography of temporomandibular joint in oblique sagittal plane

This pilot study aimed to investigate the feasibility of trans-oral ultrasonography of the temporomandibular joint (TMJ) in oblique sagittal plane. Six volunteers who were receiving residency training at Hainan Hospital of General Hospital of Chinese PLA were recruited into this study, five of them had normal TMJ and one had anterior displaced disc all of which had been confirmed by MRI. A hockey-stick-shaped ultrasound probe was placed between the cheek and maxilla to push against the mucosa lateral to posterior maxillary tuberosity, and every volunteer underwent bilateral scans. The sonographic imaging were completed successfully on the six volunteers; the condyle, the superior and the inferior head of the lateral pterygoid muscle, the disc and the maxillary vein were clearly identified in all the twelve ultrasonographic scans. The feasibility of trans-oral ultrasonography of TMJ in oblique sagittal plane was confirmed.

Linear measurement of the nucleus basalis of Meynert in Alzheimer's disease and mild cognitive impairment

The present study was performed on 12 heads of donkey’s cadavers of both sexes for different anatomic techniques and on 20 live adult donkeys for ultrasonographic approaches of local anesthetic techniques. The aim was to achieve safe desensitization of the ear canal and tympanic membrane in addition to measuring different parameters of the structures occupying the infra-auricular parotid region. The internal auricular nerve was divided into two fine branches and constituting, at its origin, a characteristic V-shape with the caudal auricular nerve. The styloid process of auricular cartilage was an adequate landmark for ultrasonographic needle-guided anesthesia for internal auricular and auriculopalpebral nerves, whereas the great auricular nerve was easily palpated subcutaneously that showed safety and success in all cases. The auricular branch of mandibular nerve joined the auriculopalpebral branch of facial nerve. The maxillary vein was descending, partially embedded within the texture of the parotid glandular tissue. The parotid gland divided into five segments was clearly demarcated by maxillary vein tributaries with three main collecting radicles pouring into the parotid duct. The mandibular duct received about 12–15 fine radicles and supplied with a separate branch from the external carotid artery. Using the Doppler sonographic technique in donkeys for diagnosis of ear affections, evaluation of retrograde sialography to salivary glands with their blood vasculature and their indices might be helpful for the detection of different critical abnormalities, such as stenosis, thrombosis, and other vasopathological affections through measuring their resistivity and pulsatility indices.

Variations of Retromandibular Vein and Its Relation to Facial Nerve Within Parotid Gland.

Maxillary vein and superficial temporal vein unite to form the retromandibular vein in the parotid gland. The facial nerve lies lateral to external carotid artery and retromandibular vein. Identifying and preserving the facial nerve is the prime motto during parotidectomy. So the variations of facial nerve and the retromandibular vein should be known so as to avoid injury to both. The variations we encountered during parotid surgery will be helpful in avoiding unexpected bleeding and injury to facial nerve.

Porcine ear: A new model in large animals for the study of facial subunit allotransplantation

In the context of experimental development of vascularized composite tissue allotransplantation (VCA), the auricular model has been described in rats and humans, but not in pigs. A porcine ear transplant, however, represents an interesting experimental composite facial subunit allotransplant because of its reduced morbidity and its translational nature but mostly because it is composed of very different tissues. In this perspective, we studied the anatomical and surgical aspects of an ear subunit VCA in pigs.Our study was performed on 18 pigs: auricular and cervical regions were dissected without preparation (n = 12) or after latex injections (n = 2) in the common carotid artery (CCA). The angiosomes of the caudal auricular artery and superficial temporal artery were studied with selective injections (n = 2). The surgical harvesting protocol was established using the caudal auricular artery as arterial pedicle, and tissue perfusion was studied with injection of Indian ink (n = 1) and angio-CT (n = 1). Finally, two in vivo orthotopic allotransplantations in four pigs were performed, followed by a short observation period.The caudal auricular artery was shown to be the dominant artery to the auricle ensure complete ear perfusion. Venous drainage relied on the caudal and rostral auricular veins, dissected down to the maxillary and external jugular veins. In vivo allotransplantations confirmed proper auricular vascularization on the sole caudal auricular artery under physiological conditions.We have described a new subunit model for experimental face VCA in large animals. Our study reports a reliable harvesting method and easily performed transplantation with a single-based arterial pedicle.

Studies of human pancreatic elastase treatment of rabbit and human vein rings to predict human therapeutic doses.

Vascular tissue contains abundant elastic fibers that contribute to vessel elasticity. Vonapanitase (formerly PRT‐201) is a recombinant human chymotrypsin‐like elastase family member 1 (CELA1) shown to cleave the elastin component of elastic fibers, resulting in increased vessel diameter. The purpose of these current studies was to determine vein diameter, wall thickness, elastin content, and vonapanitase potency in veins used in a model of arteriovenous fistula (AVF) and in patients undergoing AVF creation for hemodialysis access to guide dose selection for human trials. Rabbit linguofacial, maxillary, and external jugular veins, and human basilic and upper and lower arm cephalic veins were dissected postmortem and sectioned into 2 mm length rings. Rings were incubated in vonapanitase at 37°C at varying concentrations and times. Elastin content was estimated histologically and by quantifying desmosine, a protein cross‐link unique to elastin. Rabbit veins were substantially thinner and contained less elastin than human veins. In human veins, elastin content was greatest in basilic and least in lower arm cephalic. Vonapanitase removed elastin in a time‐ and concentration‐dependent manner in all vein types. A lower concentration of vonapanitase was required to remove elastin from rabbit relative to human veins. In summary, vonapanitase reduced the elastin content of rabbit and human veins but did so at a lower concentration in the rabbit veins. Rabbit models may overestimate the potency of vonapanitase in humans. These results indicate that human dose selection should be guided by human vein ring experiments.