Anatomy Flashcards
what is the diencephalon composed of
Thalamus
Hypothalamus
what is the role of the diencephalon
forms the central core of the cerebrum with connections to the cerebral hemispheres and midbrain
what are the 3 parts of the brainstem
midbrain
pons
medulla
what connects the hypothalamus to the pituitary gland
infundibulum
what are the 2 parts of the pituitary gland
anterior and posterior
where is the pituitary gland
pituitary fossa of the sphenoid bone
where does the pituitary fossa lie
within the sella turcica
what can a pituitary tumour cause
vision loss, specifically
Bitemporal Hemianopia
why does a pituitary tumour cause Bitemporal Hemianopia
disrupts the transmission of APS from the nasal retina bilaterally
causes lose in temporal side of visual field bilaterally
what is the surgical access to the pituitary fossa
transsphenoidal
transcranial
what lines the paranasal sinuses
mucous-secreting resp mucosa
what are the paranasal sinuses
frontal bone (frontal sinuses) maxillae (maxillary sinuses) ethmoid bone (ethmoidal air cells) sphenoid bone (sphenoid sinuses)
what is an ostia
bony drainage hole in nasal cavities for mucous
what adheres to the internal aspects of all the bones of the cranial vault
dura mater
what is the name of the tough sheet of dura mater forming a roof (diaphragm) over the pituitary fossa
the diaphragm sellae
what is the tentorium cerebelli
tough sheet of dura mater “tenting” over the cerebellum within the posterior cranial fossa has a central gap to permit the brainstem to pass through
venous drainage in the brain
venous channels within the dura mater »_space; internal jugular veins
where do the internal carotid arteries pass through to get into the skull
cavernous sinuses
where does the internal jugular veins pass through to get into the skull
jugular foraminae in the floor of the posterior cranial fossa
what connects the cavernous sinuses (R+L) anterior to the pituitary gland
anterior intercavernous sinus
where does the internal carotid artery travel to after it has entered the skull via the cavernous sinuses
carotid canal in the temporal bone
what structures are at risk in pituitary gland structures
Optic chiasm Oculomotor nerve Trochlear nerve Trigeminal nerve Abducent nerve Cavernous sinus Internal carotid artery Dura mater
what connects the right and left lobe of the thyroid gland
the isthmus
where does the isthmus lie
anterior to the 2nd and 3rd cartilages of the trachea
how can you differentiate whether a lump is on the thyroid gland
thyroid gland is attached to the larynx & trachea
therefore, lump in the gland will move with the larynx during swallowing (i.e. up then down)
where are the 4 parathyroid glands located
on the posterior surface of the thyroid gland’s lateral lobes
- superior and inferior on either side
what is a pyramidal lobe of the thyroid gland
third thyroid lobe
present in about 28-55% of the population
most commonly originates from the left lateral lobe
may extend as far superiorly as the hyoid bone
embryology - where does the thyroid gland begin its development
midline epithelial proliferation at the junction between the anterior 2/3rds and the posterior 1/3rd of the tongue
where does the gland migrate to
inferiorly whilst remaining attached to the tongue via the thyroglossal duct
where is the gland final position
C7
what muscle has a close relation to the thyroid gland
the platysma
where is the platysma located
immediately deep to the skin within the superficial fascia of the neck
what group of muscles does platysma belong to and what is its nerve supply
the muscles of facial expression
CN VII - facial nerve
what are the fascial compartments of the neck
investing (deep) (most anterior)
prevertebral (deep)
pretracheal (most posterior)
what lies between investing and pre-tracheal fascia
the 2 carotid sheaths
what does prevertebral enclose
cervical vertebrae & the postural neck muscles
what does investing fascia enclose
encloses all the other neck fascial compartments
encloses 2 pairs of muscles:
- trapezius
- sternocleidomastoid
what does pre tracheal fascia enclose
the strap muscles
the thyroid gland the trachea the oesophagus
the recurrent laryngeal nerves
what is enclosed in the carotid sheaths
the internal jugular veins
the carotid arteries
vagus nerve
deep cervical lymph nodes
where does the retropharyngeal space lie
between the pre tracheal and the prevertebral fascia
what fascia is the sternocleidomastoid enclosed in
investing fascia
where are the carotid sheaths
deep to the investing fascia & located anterolaterally in the neck either side of the thyroid gland
what is the blood supply of the thyroid gland
superior and inferior thyroid arteries
what is the inferior thyroid artery a branch of
subclavian artery
what is the superior thyroid artery a branch of
external carotid artery
what is the venous drainage of the thyroid
superior thyroid vein
middle thyroid vein
inferior thyroid vein
where do the thyroid veins drain to
superior and middle thyroid veins - internal jugular vein
inferior thyroid vein
- brachiocephalic veins
all then drain into SVC
what is the lymph drainage of the thyroid
pre-tracheal and para-tracheal lymph nodes
which then drain into the superior and inferior deep cervical nodes
what branches of the vagus nerve supply the larynx
superior laryngeal nerve
recurrent laryngeal nerve
what are the strap muscles
sternohyoid
omohyoid
thyrohyoid
sternothyroid
what is at risk during an operation of the thyroid
recurrent laryngeal nerve
what does the recurrent laryngeal nerve supply
skeletal muscles that move the vocal cords
what would unilateral and bilateral injury cause
unilateral - hoarseness/weakness of the voice, weak cough
bilateral - aphonia (inability to produce sound), inability to close the rima glottidis or produce a good cough
what fascia is the thyroid enclosed in
pretracheal (deep) fascia
