The accessory nerve Flashcards
Describe the origin of the accessory nerve and its associated nuclei
The accessory nerve is the only cranial nerve that doesnt have its nuclei in the cranium.
What type of nerve is the accessory nerve?
Its motoric. (CN VI - matter)
What type of innervation does the accessory nerve carry?
That is disputed. Either special viceral efferent fibers due to a close relationship to nucleus ambigous.
OR
general somatic efferents due to the unknown embryological origins of SCM and Trapezius muscle.
What cistern does the accessory nerve enter through?
The posterior cerebellomedullary cistern
The internal ramus of the accessory nerve emerges from what part of the brain?
medulla oblongata
Through which opening (Foramen) does the accessory nerve (Nervus accessorius, CN XI) exit the skull?
Jugular foramen
A glomus tumor arising from the jugular foramen might cause Vernet’s syndrome. Which CN are affected?
Vagus nerve
Acessory nerve
Glossopharyngeal nerve
Nervus Accessorius is a motornerve, but it carries both efferent motorfibers and afferent proprioception from the two main muscles it supplies. Which?
Trapezius and Sternocleidomastoideus.
What vein passes through the jugular foramen together with the accessory nerve?
The left internal jugular vein
What region of the neck does the spinal accessory nerve enter as it leaves the posterior border of the sternocleidomastoid muscle?
The posterior triangle of the neck.
What other CN carries fibers from nucleus Ambiguus?
CN X (Vagus)
Which nucleus provides efferent motor fibers for the accessory nerve through which it innervates the pharyngeal muscles, the larynx and the palate?
Nucleus Ambiguus
From what structure does the external ramus of the accessory nerve arise?
From the spinal cord.
Which artery cross the accessory nerve (nervus accessorius, CN XI) as it moves across the transverse process of the atlas?
The occipital artery
Which of the muscles are closely related anteriorly to the accessory nerve (nervus accessorius, CN XI) as it courses in the anterior cervical triangle (trigonum cervicale anterius)?
*Stylohyoid
*Digastric
