Term
What lies superficial to the suboccipital triangle? |
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Definition
•This is a triangle placed very deeply in the back below the occipital bone. •The following structures have to be identified and reflected before the suboccipital triangle is approached: •Skin •Superficial fascia, greater & 3rd occipital nerve, occipital artery , dorsal rami of cervical nerves •Deep fascia •Trapezius muscle •Splenius capitis (from the ligamentum nuchae & spines of C7 & upper 6 thoracic vertebrae, directed upwards and laterally and is inserted into the mastoid process) •Semispinalis capitis (From the transverse processes of upper 4 thoracic vertebrae, directed straight upwards, has shiny appearance & tendinous intersections and is inserted into the medial part of the area between the superior and inferior nuchal lines •Longissimus capitis origin same as semispinalis & inserted to the mastoid process •Nerve supply of the splenius, semispinalis & longissimus- from dorsal rami of cervical nerves •Deep to semispinalis capitis there is suboccipital triangle: |
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Term
•What is the splenius capitus? |
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Definition
·Splenius capitis (from the ligamentum nuchae & spines of C7 & upper 6 thoracic vertebrae, directed upwards and laterally and is inserted into the mastoid process – it is a lateral rotator of the neck) |
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Term
•What is the semispinalis capitis? |
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Definition
·Semispinalis capitis (From the transverse processes of upper 4 thoracic vertebrae, directed straight upwards, has shiny appearance & tendinous intersections and is inserted into the medial part of the area between the superior and inferior nuchal lines – it is a lateral rotator of the neck) • |
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Term
•What are the attachments for the longissimus capitis? |
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Definition
Longissimus capitis origin same as semispinalis (transverse process of upper 4 thoracic vertebrae) & inserted to the mastoid process |
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Term
•What muscles form the boundaries of the suboccipital triangle? |
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Definition
•Following muscles form the boundaries of the suboccipital triangle: •Rectus capitis posterior major: arises from the spine of C2 and is inserted into the lateral part of the area between the inferior nuchal line and the posterior margin of foramen magnum •Rectus capitis posterior minor: arises from the posterior tubercle of the atlas and is inserted into the medial part of the area between the inferior nuchal line and the posterior margin of the foramen magnum •Obliqus capitis inferior: it arises from the spine of Axis (second cervical vertebra) and is inserted into the undersurface of the transverse process of atlas. •Obliqus capitis superior: arises from the superior surface of the transverse process of the atlas and is inserted into the lateral part of the area between the superior and inferior nuchal lines. |
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Term
•What are the contents of the suboccipital triangle? |
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Definition
•Contents: •3rd part of the vertebral artery & its muscular branches •Dorsal ramus of 1st cervical nerve (suboccipital nerve) it supplies all the small muscles of the suboccipital triangle •thick connective tissue •Suboccipital plexus of veins |
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Term
What is important about the greater occipital nerve? |
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Definition
•Greater occipital nerve: (dorsal ramus of C2) It is the thickest cutaneous nerve of the body. It winds round the obliqus capitis inferior muscles and runs in the roof of the triangle before it pierces the semispinalis capitis and trapezius to supply the skin of the back of the scalp |
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Term
What can vertebral insufficiency lead to? |
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Definition
In vertebral insufficiency when the head is turned backwards as in taking reverse in a vehicle, there may be vertigo. This is due to the compression of the vertebral artery in the triangle. |
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Term
•How is the posterior cranial fossa approached during operation? |
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Definition
•The suboccipital triangle is used to approach the posterior cranial fossa in the operation connected with that fossa and cerebellum |
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Term
What is cisternal puncture of cisternal magna? |
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Definition
•This is also used in cisternal puncture of cisternal magna to withdraw CSF. This is done when lumbar puncture is contraindicated as in the case of a block between the cranial and spinal subarachnoid spaces. |
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Term
•What is the thyroid gland? |
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Definition
•It is a ductless endocrine gland present in the anterior median region of the neck •It is covered by the pretracheal fascia which forms its false capsule •Because false capsule is attached to thyroid cartilage and hyoid, thyroid moves with deglutition •The true capsule is the thickened fascia which surrounds the gland. •Blood vessels form plexuses deep to the true capsule. •The gland has right and left lobes and an isthmus •Isthmus lies in front of the 2nd, 3rd & 4th tracheal rings •Each lobe has a superior pole which is limited by the attachment of pretracheal fascia & sternothyroid to the oblique line of thyroid cartilage. (Note: that is the reason why any enlargement of gland is never directed upwards) •Inferior pole usually lies at the level of fifth tracheal ring •Parathyroid glands lie along the posterior border of the thyroid gland |
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Term
What is the extent of the Thyroid gland? |
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Definition
•Extent: •It extends from the level of the oblique line of the thyroid cartilage to the level of 5th or 6th tracheal ring (C5- T1) |
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Term
•What does each lobe of the thyroid gland have? |
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Definition
•Each lobe has an apex, a base, & a superficial, medial and posterolateral surface. |
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Term
•What is related to the superficial surface of the thyroid gland? |
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Definition
•Superficial surface: (anterolateral surface) • Lies deep to the floor of muscular triangle & is related to the following muscles: •Sternohyoid, sternothyroid and lower part of sternocleidomastoid muscles |
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Term
•What is related to the medial surface of the thyroid gland? |
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Definition
•Medial surface: • It is related to the following: •2 tubes: trachea and esophagus •2 nerves: external and recurrent laryngeal nerve •2 muscles: cricothyroid and inferior constrictor muscle of pharynx •2 cartilages: thyroid and cricoid •2 arteries: superior thyroid and inferior thyroid |
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Term
•What structures are related to the posterolateral surface of the thyroid gland? |
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Definition
•Posterolateral surface: • It is related to the carotid sheath and its contents at this level: •The common carotid artery •The internal jugular vein •The vagus nerve (lies between the two) |
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Term
•Where does the parathyroid gland lie? |
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Definition
•Posterolateral surface: • It is related to the carotid sheath and its contents at this level: •The common carotid artery •The internal jugular vein •The vagus nerve (lies between the two) |
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Term
•Where does the parathyroid gland lie? |
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Definition
•Parathyroid glands lie along the posterior border of the thyroid gland between the true and false capsules. |
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Term
•What is the isthmus of the thyroid gland? |
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Definition
•Joins the two lobes across the midline. It lies in front of 2nd, 3rd & 4th tracheal rings. |
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Term
•What is the pyramidal lobe? |
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Definition
•It is present in 50% cases. It varies in size. It extends superiorly from the isthmus of the thyroid gland, usually to the left of the midline. A band of connective tissue may extend from the apex of the pyramidal lobe to the hyoid bone. This is called levator glandulae thyroideae. This may contain accessory thyroid tissue. It is a remnant of the thyroglossal duct. |
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Term
•How is the thyroid developed? |
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Definition
•Development: As a diverticulum from the floor of the developing oral cavity in the midline behind the tuberculum impar. It grows as thyroglossal duct. It migrates to the adult position. The proximal part of the duct disappears. Failure to do so results in thyroglossal duct and thyroglossal cysts. •The site of the diverticulum is seen in the adult tongue as Foramen caecum at the junction of the anterior ⅔ and posterior ⅓ of the dorsum of the tongue. •Parafollicular cells develop from the neural crest and ultimobronchial body. |
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Term
•What is accessory thyroid tissue? |
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Definition
•Accessory thyroid tissue: It may appear anywhere along the embryonic course of the thyroglossal duct. It may be found lateral to the thyroid cartilage, on the thyrohyoid muscle. |
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Term
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Definition
•A non-neoplastic and non-inflammatory enlargement of the thyroid gland is called goiter. It results from lack of Iodine. The enlarged gland may compress the trachea, esophagus and recurrent laryngeal nerves. However, it does not extend superiorly because of the attachment of the Sternothyroid & sternohyoid muscles to the thyroid cartilage and hyoid bone. |
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Term
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Definition
•Partial, subtotal or total. Care should be exercised while performing surgery- recurrent laryngeal nerves, parathyroid glands are in danger. Parathyroids are safe during subtotal thyroidectomy because posterior part of the thyroid gland is usually preserved. •Inferior parathyroid gland is more variable in position due to its developmental origin. |
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Term
•What is the arterial supply of the thyroid gland? |
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Definition
•Arterial supply of the thyroid gland: •Superior thyroid artery •Inferior thyroid artery •Thyroidea ima (in 10% cases) •Superior thyroid artery is a branch of the external carotid artery and the inferior thyroid artery is a branch of the thyrocervical trunk. |
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Term
| What is the superior thyroid artery a branch of? |
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Definition
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Term
| What is the inferior thyroid artery a branch of? |
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Definition
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Term
•What runs close to the superior thyroid artery? |
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Definition
•The superior thyroid artery is accompanied by the external laryngeal nerve which supplies the cricothyroid muscle. The external laryngeal nerve lies closely related to the artery in the proximal part of its course. As it approaches the gland, it moves more medially and thus gets separated from the superior thyroid artery. That is the reason why the superior thyroid artery is ligated as near to the gland as possible to avoid injury to the external laryngeal nerve. |
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Term
•Where is the inferior thyroid artery closest to the recurrent laryngeal nerve? |
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Definition
•The inferior thyroid artery is a branch of the thyrocervical trunk (from 1st part of subclavian) and it turns transversely at the level of 6th cervical vertebra and goes behind the common carotid artery. As it approaches the posterior aspect of the gland, it is closely related to the corresponding recurrent laryngeal nerve. That is the reason why the inferior thyroid artery is ligated as far away as possible from the gland to avoid injury to the recurrent laryngeal nerve. |
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Term
•What is a symptom of the injury of the recurrent laryngeal nerve? |
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Definition
•If recurrent laryngeal nerve is injured, it results in the hoarseness of the voice as most of the muscles of the larynx are supplied by the recurrent laryngeal nerve. |
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Term
•What is the importance of thyroidea ima? |
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Definition
•The other artery which often supplies the thyroid gland is the thyroidea ima. •It arises either from the arch of aorta or the brachiocephalic artery and ascends in front of trachea to reach the lower end of the isthmus of thyroid gland. •It is inadvertently cut during tracheotomy operations. Following its injury, usually it retracts into the thorax and it goes very difficult for the surgeon to get the bleeding stopped. This might result in an iatrogenic catastrophe. Possible presence of this artery must be considered when performing midline procedures below the isthmus. |
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Term
•What is the venous drainage of the thyroid gland? |
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Definition
•Venous drainage of thyroid gland: • Three paired veins usually drain the thyroid gland. •The superior thyroid vein •The middle thyroid vein •The inferior thyroid vein. |
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Term
| Do the superior, middle and inferior thyroid veins accompany the corresponding arteries? |
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Definition
•Out of these three, only the superior thyroid vein accompanies the corresponding artery. It opens into the internal jugular vein. |
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Term
| What does the middle thyroid vein drain into? |
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Definition
•The middle thyroid vein does not accompany any artery and it directly opens into the internal jugular vein. |
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Term
•What does the inferior thyroid vein open into? |
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Definition
•The inferior thyroid veins, the right and left emerge at the lower border of the isthmus and cross the front of the trachea. It is here that they pose problem. They might get cut and start bleeding during tracheotomy operation. They open into the corresponding brachiocephalic vein. •Often the right and left inferior thyroid veins join together to form a single inferior thyroid vein which usually opens into the left brachiocephalic vein. It does not accompany the corresponding artery. |
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Term
•What is the lymphatic drainage of the thyroid gland? |
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Definition
•Lymph vessels of thyroid are drained into the following lymph nodes: –Prelaryngeal –Pretracheal –Deep cervical lymph nodes –Some nodes may open directly into thoracic duct or the right lymphatic duct. |
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Term
•What is the nerve supply of the thyroid gland? |
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Definition
•Sympathetic nerve supply from superior middle and inferior cervical sympathetic ganglia branches that accompany the arteries. These are vasomotor, not secretomotor. Endocrine secretion from the gland is hormonally regulated by the pituitary gland. |
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Term
•What is the development of the parathyroid gland? |
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Definition
•Development of Parathyroid glands: •The superior parathyroid gland is developed from the fourth pharyngeal pouch and the inferior parathyroid gland is developed from the third pouch. That is the reason why the inferior parathyroid gland may descend into the thorax along with the thymus due to the common developmental origin. •Superior parathyroid is also called Parathyroid IV •Inferior parathyroid is also called parathyroid III |
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Term
•What is the blood supply of the parathyroid gland? |
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Definition
•Blood supply: mainly by the inferior thyroid artery but the anastomosis between the superior and inferior thyroid artery supplies |
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Term
•What is the venous drainage of the parathyroid gland? |
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Definition
•Veins drain into the thyroid plexus of veins |
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Term
•What is the lymphatic drainage of the parathyroid gland? |
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Definition
•Lymph vessels drain into the deep cervical lymph nodes |
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Term
•What is the nerve supply of the parathyroid gland? |
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Definition
•Nerve supply: usually by sympathetic branches coming from the middle cervical sympathetic ganglion |
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Term
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Definition
•Tetany: If parathyroids are removed, there is generalized convulsion caused by lowered calcium level. This is termed tetany. |
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Term
•What are the differences between the right and the left subclavian arteries? |
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Definition
•The right subclavian artery is a branch of the brachiocephalic trunk •The left subclavian artery is a branch of the arch of aorta •The left subclavian has both thoracic and cervical course •The right subclavian has only the cervical course. •The right subclavian and the cervical course of the left subclavian arteries: •They begin at the level of the corresponding sternoclavicular joints. •They terminate at the outer border of the first rib and continue as the corresponding axillary artery. |
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Term
•What are the parts of the subclavian artery? |
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Definition
•Subclavain artery is divided into three parts by the scalenus anterior muscle •The first part lies medial to the scalenus anterior muscle •The second part lies behind the scalenus anterior muscle •The third part lies lateral to the scalenus anterior |
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Term
•What are the relations of the first part of the subclavian artery? |
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Definition
•First part of the subclavian artery: •Anterior relations:Skin, superficial fascia, investing layer of deep cervical fascia, Sternocleidomastoid, internal jugular vein and vagus nerve •Anteroinferiorly there is subclavian vein which is joined by the internal jugular vein to form the corresponding brachiocephalic vein •Posterior: it is related to the apex of the lung and cervical pleura. |
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Term
•What are the branches of the first part of the subclavian artery? |
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Definition
•Vertebral artery extends superiorly •Internal thoracic artery extends inferiorly •Thyrocervical trunk. |
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Term
•What are the branches of the thyrocervical trunk? |
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Definition
•Thyrocervical trunk ascends along the medial border of the scalenus anterior and gives three branches: •Inferior thyroid •Suprascapular •Transverse cervical (gives a deep and an superficial branch) •Inferior thyroid turns transversely behind the internal jugular vein and the common carotid artery at the level of the 6th cervical vertebra. It gives glandular branches and the ascending cervical artery. It also gives the inferior laryngeal artery. |
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Term
| What is the inferior laryngeal artery a branch of? |
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Definition
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Term
| What is the ascending cervical artery a branch of? |
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Definition
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Term
•What are the relations of the 2nd part of the subclavian artery? |
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Definition
•Second part of the subclavian artery: •It lies behind the scalenus anterior •Anterior relations: Skin, superficial fascia, investing layer of deep cervical fascia, subclavian vein, phrenic nerve and scalenus anterior muscle •Posterior relations: It is related to the lower trunk of the brachial plexus and scalenus medius. |
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Term
•What are the branches of the 2nd part of the subclavian artery? |
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Definition
•Branches: •Costocervical trunk is the only branch of the second part •The costocervical trunk arches over the cervical pleura and reaches the neck of the first rib where it divides into the superior intercostal and deep cervical artery |
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Term
•What are the relations of the 3rd part of the subclavian artery? |
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Definition
• •This part lies lateral to the scalenus anterior in the lower part of the floor of the posterior triangle. •Anterior: skin and fasciae, EJV and its tributaries, supraclavicular nerves, clavicle, subclavius •Posterior: Lower trunk of brachial plexus and scalenus medius •Superior: upper and middle trunks of brachial plexus •Inferior: 1st Rib |
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Term
•What are the branches of the 3rd part of the subclavian artery? |
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Definition
•Branches: It does not usually give any branch. But often deep branch of the transverse cervical artery arises from it and that branch is called dorsal scapular artery. |
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Term
•What is compressed to stop bleeding of a ruptured upper limb artery? |
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Definition
•The 3rd part of the subclavian artery is usually pressed against the first rib in the greater supraclavicular fossa to stop the bleeding from a ruptured upper limb artery. |
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Term
•What is scalenus anterior syndrome? |
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Definition
•Scalenus anterior syndrome: The lower trunk of brachial plexus and the second part of the subclavian artery are compressed by the spasm of scalene muscles or by the cervical rib. Then the patient feels pain on the medial side of the hand and there is weak radial pulse on the corresponding side of the limb. |
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Term
•What is Adson’s test used for? |
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Definition
•Adsons test: In scalenus anterior syndrome the radial pulse becomes weak when the head is turned to the affected side. |
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Term
| True or false: both recurrant laryngeal nerves hook around the subclavian arteries |
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Definition
False: •The first part of the subclavian artery is hooked around on the right side by the right recurrent laryngeal nerve. However the left recurrent laryngeal nerve does not hook around the left subclavian artery. |
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Term
•What is the ansa subclavia? |
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Definition
•Ansa subclavia: It is a loop of sympathetic fibers which connect the middle cervical with the inferior cervical sympathetic ganglia. This loop goes around the first part of right and left subclavian arteries. |
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Term
•What is the origin of the vertebral artery and which foramen tranversarium does it enter first? |
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Definition
•Origin: It arises from the first part of the subclavian artery •It is divided into four parts •Vertebral artery does not enter the foramen transverserium of the Transverse process of C7, but it does enter the foramen transverserium of C6-C1 |
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Term
•What is related to the 1st part of the vertebral artery? |
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Definition
•The first part lies in the scaleno-vertebral triangle bounded medially by the longus colli muscle and laterally by the scalenus anterior muscle. The base is formed by the first part of the subclavian artery. The first part extends from its origin to the foramen transversarium of the 6th cervical vertebra. It gives no branches here. |
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Term
•What are the relations of the 2nd part of the vertebral artery? |
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Definition
•The second part lies in the foramen transversaria of upper six cervical vertebrae. It gives spinal branches. |
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Term
•What are the relations of the 3rd part of the vertebral artery? |
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Definition
•The third part lies in the floor of the suboccipital triangle superior to the posterior arch of the atlas. The suboccipoital nerve separates it from the posterior arch. It gives muscular branches to the muscles of the region. |
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Term
•What is the relation of the fourth part of the vertebral artery? |
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Definition
•The fourth part of the vertebral artery is present inside the cranium. It passes through the foramen magnum. It pierces the duramater and arachnoid mater. |
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Term
•What is the termination of the vertebral artery? |
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Definition
•Termination: The two vertebral arteries unite at the lower border of the pons to form basilar artery. •(Only artery where two branches meet to form a single artery in the cranium at the base of the brain) •The fourth part of the vertebral artery gives five branches: •Anterior spinal artery •Posterior spinal artery •Posterior inferior cerebellar artery •Medullary branches •Meningeal branches |
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Term
•What is the common carotid artery? |
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Definition
•Common carotid artery •The right common carotid artery is a branch of the brachiocephalic trunk at the level of right sternoclavicular joint. •The left common carotid artery is a branch of the arch of aorta. It enters the neck behind the left sternoclavicular joint. •The common carotid artery lies inside the carotid sheath medial to the internal jugular vein. The vagus nerve lies inside the carotid sheath more posteriorly between the CCA and IJV. •It divides at the level of the upper border of the thyroid cartilage which corresponds to the level of the disc between the C3 and C4 vertebrae •Its two terminal branches are: •The external carotid •The internal carotid •Common carotid artery does not give branches except its terminal branches |
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Term
•What are the anterior relations of the common carotid artery? |
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Definition
•Anteriorly it is related to the following: •SCM •Sternohyoid •Sternothyroid •Lobe of the thyroid gland •Ansa cervicalis •Superior belly of omohyoid crosses the artery at the level of C6 vertebra. At this point of crossing there is jugulo-omohyoid lymph node. This is the lymph node of the tongue. |
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Term
•What are the posterior relations of the common carotid artery? |
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Definition
•Inferior thyroid artery •Cervical sympathetic chain posterior to the carotid sheath |
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Term
•What is the carotid sinus? |
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Definition
•It is the dilatation of the proximal part of the beginning of the internal carotid artery and sometimes the distal part of the common carotid artery. There are baroreceptors in it which are stimulated by pressure changes in the artery. This is supplied by the carotid sinus nerve, a branch of the glossopharyngeal nerve. |
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Term
•What is the carotid sinus? |
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Definition
•It is the dilatation of the proximal part of the beginning of the internal carotid artery and sometimes the distal part of the common carotid artery. There are baroreceptors in it which are stimulated by pressure changes in the artery. This is supplied by the carotid sinus nerve, a branch of the glossopharyngeal nerve. |
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Term
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Definition
•It is the chemoreceptor present at the bifurcation of the common carotid artery. This is usually removed in the dissection along with the connective tissue and fat. |
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Term
•Where are the pulsations of the common carotid artery easily felt? |
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Definition
•The pulsations of common carotid artery are easily felt against the anterior tubercle of the transverse process of 6th cervical vertebra. The artery can be compressed against this tubercle (carotid tubercle). |
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Term
•What leads to bradycardia in relation to common carotid artery? |
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Definition
•Hypersensitive carotid artery: In some individuals the carotid artery is hypersensitive and any pressure on the artery leads to bradycardia and sometimes cardiac arrest. In such cases the common carotid pulse should not be taken. |
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Term
•What is the external carotid artery? |
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Definition
•This is one of the two terminal branches of the common carotid arising at the level of disc between C3&C4 vertebrae at the level of the upper border of thyroid cartilage. •It soon leaves the carotid sheath and has a curved upward course in the neck. It enters the parotid gland . |
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Term
•How does the external carotid artery terminate? |
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Definition
•Termination: inside the parotid gland, at the level behind the neck of the mandible it terminates by dividing into superficial temporal and maxillary arteries. •It becomes progressively narrow because of its branches. •It curves forwards, upwards and medially at first, then backwards, upwards and laterally. |
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Term
•What strucutres cross the external carotid artery? |
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Definition
•It is crossed by: •Posterior belly of digastric, stylohyoid and hypoglossal nerve in the neck and within the parotid gland, by the facial nerve |
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Term
•What is the lateral relation to the external carotid artery? |
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Definition
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Term
•What comprises the medial boundaries of the external carotid artery? |
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Definition
•Medial to the artery are styloid process, internal carotid artery and the structures that lie between the ICA and ECA. •Structures between the external carotid and internal carotid arteries are: •styloid process •styloglossus •Stylopharyneus •Glossopharyngeal nerve •Pharyngeal branch of vagus •part of the parotid gland |
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Term
•What are the branches of the external carotid artery? |
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Definition
•External carotid is the artery for the structures outside of the cranium and gives the following branches: •Ascending pharyngeal •Superior thyroid •Lingual •Facial •Maxillary •Posterior auricular •Occipital •Superficial temporal |
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Term
•What is the internal carotid artery? |
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Definition
•Internal carotid artery •This is the continuation of the common carotid artery and is one of its terminal branches. It begins at the level of the upper border of the thyroid cartilage which corresponds to the disc between C3 and C4 •It enters the carotid canal to enter the middle cranial fossa & runs in the cavernous sinus to enter base of brain where it terminates by dividing into anterior and middle cerebral arteries. •This lies inside the carotid sheath. •Both internal and external carotid arteries lie deep to posterior belly of digastric and stylohyoid muscles. These muscles act like strap to these arteries and serve to keep them fastened to their place. •Below the level of the posterior belly of digastric muscle, hypoglossal nerve crosses superficial to the internal carotid artery. •It does not lie in the parotid gland. It is separated from the parotid gland and ECA by the styloid process and structures attached to it. |
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Term
•What is the internal carotid artery? |
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Definition
•This is the continuation of the common carotid artery and is one of its terminal branches. It begins at the level of the upper border of the thyroid cartilage which corresponds to the disc between C3 and C4 •It enters the carotid canal to enter the middle cranial fossa & runs in the cavernous sinus to enter base of brain where it terminates by dividing into anterior and middle cerebral arteries. •This lies inside the carotid sheath. •Both internal and external carotid arteries lie deep to posterior belly of digastric and stylohyoid muscles. These muscles act like strap to these arteries and serve to keep them fastened to their place. •Below the level of the posterior belly of digastric muscle, hypoglossal nerve crosses superficial to the internal carotid artery. •It does not lie in the parotid gland. It is separated from the parotid gland and ECA by the styloid process and structures attached to it. |
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Term
•What are the posterior relations to the internal carotid artery? |
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Definition
•Sympathetic trunk and superior cervical sympathetic ganglion •Vagus & Superior laryngeal nerve |
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Term
•What are the branches of the internal carotid artery in the neck? |
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Definition
•Internal carotid artery does not give any branch in the neck. All its distribution is intracranial. |
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Term
•When is endarterectomy performed? |
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Definition
•Thick plaques may block the internal carotid arteries partially or completely. In such cases endarterectomy operation is performed. In such operation one has to be careful of various nerves met in the region. |
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Term
•What is the beginning of the internal jugular vein? |
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Definition
•Begins as the continuation of the sigmoid sinus at the jugular foramen |
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Term
•How does the internal jugular vein terminate? |
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Definition
•In the root of the neck it joins with the subclavian vein to form the brachiocephalic vein behind the medial end of the clavicle. |
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Term
•What dilatations are part of the internal jugular vein? |
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Definition
•It has 2 dilatations- one at the beginning (superior bulb) and the other at the termination (inferior bulb) |
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Term
•What are some of the relations of the internal jugular vein? |
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Definition
•It runs vertically in the neck within the carotid sheath. It lies lateral to the internal and common carotid arteries. •Between the IJV and ICA are 9th, 11th & 12th cranial nerves. •Between and deep to these lies the vagus nerve. •IJV is overlapped by the sternocleidomastoid muscle •The part of the carotid sheath covering the IJV is thin to allow for expansion during increased venous return |
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Term
•What are some of the relations of the internal jugular vein? |
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Definition
•It runs vertically in the neck within the carotid sheath. It lies lateral to the internal and common carotid arteries. •Between the IJV and ICA are 9th, 11th & 12th cranial nerves. •Between and deep to these lies the vagus nerve. •IJV is overlapped by the sternocleidomastoid muscle •The part of the carotid sheath covering the IJV is thin to allow for expansion during increased venous return |
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Term
•What are the tributaries of the Internal jugular vein? |
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Definition
•Inferior petrosal sinus •Lingual vein •Occipital vein •Common facial vein •Superior thyroid vein •Middle thyroid vein •Note: Inferior thyroid vein is not a tributary of the IJV. It drains into the brachiocephalic vein |
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