Anatomy - Block 2 Flashcards
What innervates the platysma?
Cervical branch of the facial nerve
Where is the platysma?
In superficial fascia, from lower margin of the mandible to the upper regions of the thorax.
What does the investing layer of cervical fascia enclose?
Sternocleidomastoid muscle and trapezius muscle
What layer of cervical fascia surrounds the thyroid cartilage?
Pretracheal or visceral fascia
What does the accessory nerve leave the cranial cavity through?
Jugular foramen
What nerves supplies all strap muscles?
Ansa cervicalis (from ventral rami - motor nerves of C1-C3)
What is located outside the carotid sheath?
Sympathetic chain
What is the carotid body and sinus?
The carotid sinus - pressure receptor
The carotid body - chemoreceptor (bicarb, etc. in blood)
-Both supplied with sensory fibers from the glossopharyngeal nerve (CN IX)
What are the main branches from bottom up of the external carotid artery?
- Superior thyroid
- Superior laryngeal
- Lingual
- Facial
What does the internal branch of the superior larygneal nerve supply?
Its a branch of the vagus. It is sensory to that larynx above the vocal cords.
What does the external branch of the superior laryngeal nerve supply?
Inferior pharyngeal constrictor muscles and the cricothyroid muscles.
What can a cricothyrotomy do?
Cutting cricothyroid ligament. It can quickly relieve an acute respiratory obstruction.
What is the path of the accessory nerve (CN XI)?
It originates in upper spinal cord segments and passes through the foramen magnum. It continues through the jugular foramen and then innervates SCM and trapezius muscles.
What nerves supplies sensory to most of the pharynx?
Glossopharyngeal nerve (CN IX)
What is the vagus nerve nucleus?
Nucleus ambiguus
What does the vagus nerve supply motor and sensory nerves to?
Motor - muscles of the pharynx (except stylopharyngeus) and larynx
Sensory - larynx and part of the pharynx
What motor nuclei are near the midline?
III, IV, VI and XII
What supplies the ciliary ganglion?
Oculomotor Nerve (CN III) - parasympathetic preganglionic fibers
What innervates the pterygopalatine ganglion?
Facial Nerve!
***What is contained in the middle cerebellar peduncle?
Afferents to the cerebellum from pontine nuclei (pontocerebellar fibers!)
What is sensory to the posterior 1/3 of tongue (taste) and motor to the stylopharyngeus muscle?
Glossopharyngeal nerve (CN IX)
What is the superior colliculus?
It contains superior colliculus nucleus
-Involved in visual reflexes
What is the inferior colliculus?
Involved in auditory related relay nucleus.
What is in the cerebral peduncle (crus)? Where is it?
Location of corticospinal, corticobulbar and corticopontine tracts. It is on the sides (lateral) of the superior and inferior colliculi.
What does the superior cerebellar peduncle hold?
Efferent from cerebellum (cerebello-rubro-thalamic tract); ventral spinocerebellar tract afferents
What is the facial colliculi?
Bumps in the forth ventricle under the pons - where facial motor nerve fibers pass over abducens nucleus
What is the sulcus limitans?
Groove in fourth ventricle that separates the motor and sensory nerves!
Where is the vestibular area?
Under cut away pons in fourth ventricle - it holds vestibular nuclei
What is in the cuneate tubercle (fasciculus)?
Cuneate nucleus (touch/proprioception/two-point discrimination) for UPPER extremity - lateral spinal cord
What is the gracile tubercle (fasciculus)?
Touch/proprioception for LOWER extremity - medial spinal cord
What is the tectum above?
Cerebral aquaduct! It also contains the superior and inferior colliculi!
What does the tegmentum contain?
Dopaminergic fibers/cell bodies