Course
It is a continuation of the axillary vein.
It begins at the outer border of the first rib, and ends at the medial border of the scalenus anterior
by joining the internal jugular vein to form the brachiocephalic vein.
It lies:
a. In front of the subclavian artery, the scalenus anterior and the right phrenic nerve
b. Behind the clavicle and the subclavius
c. Above the first rib and pleura.
Its tributaries are:
a. The external jugular vein
b. The dorsal scapular vein
c. The thoracic duct on the left side
d. The right lymphatic duct on the right side.
INTERNAL JUGULAR VEIN
Course
1. It is a direct continuation of the sigmoid sinus.
It begins at the jugular foramen, and ends behind the sternal end of the clavicle by joining the subclavian vein to form the brachiocephalic vein.
2. The origin is marked by a dilation, the superior bulb which lies in the jugular fossa of he temporal bone,
beneath the floor of the middle ear cavity.
The termination of the vein is marked by the inferior bulb which lies beneath the lesser supraclavicular fossa.
Relations
Superficial
1. Sternocleidomastoid
2. Posterior belly of digastric
3. Superior belly of omohyoid
4. Parotid gland
5.. Styloid process
6 The internal carotid artery, and the glossopharyngeal, vagus, accessory and hypoglossal cranial nerves
(at the base of skull).
Posterior
1. Transverse process of atlas
2. Cervical plexus
3. Scalenus anterior
4. First part of subclavian artery.
Medial
1. Internal carotid artery
2. Common carotid artery
3. Vagus nerve
Tributaries
1. Inferior petrosal sinus
2. Common facial vein
3. Lingual vein
4. Pharyngeal veins
5. Superior thyroid vein
6. Middle thyroid vein
The thoracic duct opens into the angle of union between the left internal jugular vein and the left
subclavian vein.
The right lymphatic duct opens similarly on the right side.
In the middle of the neck, the internal jugular vein may communicate with the external jugular vein
through the oblique jugular vein which runs across the anterior border of the sternocleidomastoid.
Clinical Anatomy
Deep to the lesser supraclavicular fossa, the internal jugular vein is easily accessible for recording of venous pulse tracings.
The vein can be cannulated by direct puncture in the interval between sternal and clavicular heads of sternocleidomastoid muscle.
In congestive cardiac failure or any other disease where venous pressure is raised, the internal jugular vein is markedly dilated and engorged.
BRACHIOCEPHALIC VEIN
1. The right brachiocephalic vein (2.5 cm long) is shorter than the left (6 cm long).
2. Each vein is formed behind the sternoclavicular joint,by the union of the internal jugular vein and the
subclavian vein.
3. The right vein runs vertically downwards.
The left vein runs obliquely downwards and to the right behind the upper half of the manubrium sterni.
The two brachiocephalic veins unite at the lower border of the right first costal cartilage to form the superior vena cava.
4. The tributaries correspond to the branches of the first part of the subclavian artery.
These are as follows:
Right Brachiocephalic
a. Vertebral
b. Internal thoracic
c. Inferior thyroid
d. First posterior intercostal.
Left Brachiocephalic
a. Vertebral
b. Internal thoracic
c. Inferior thyroid
d. First posterior intercostal.
e. Left superior intercostal.
f. Thymic and pericardial veins.
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Tq mam
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