Anatomy: pituitary gland Flashcards
what glands lie in the cranial cavity
hypothalamus and pituitary
what glands lie in the neck
4 parathyroid glands and thyroid
what glands lie in the abdomen
2 adrenal glands and pancreas
what glands lie in the pelvis and peritoneum
pelvis: 2 ovaries
perineum: 2 testes
what is the diencephalon
the thalamus + hypothalamus
what does the diencephalon form
central core of the cerebrum that connects the right and left hemispheres and the midbrain
where does the hypothalamus lie
superior and anterior to brainstem
what makes up the brainstem superior to inferior
midbrain, pons, medulla, oblongata
what connects the pituitary gland to the hypothalamus
infundibulum
what does rathke’s pouch develop into in embryology
anterior pituitary lobe
what does the infubdibulum develop into in embryology
posterior pituitary lobe
which pituitary lobe is an extension of the hypothalamus
posterior
what is another term for the posterior pituitary
neurohypophysis
what does the posterior pituitary secrete
oxytocin and vasopressin (ADH)
how are hormones transported from the hypothalamus to the posterior pituitary
within axoplasm (cytoplasm of axons) by axoplasmic transport - neurosecretory
what activates the anterior pituitary to secrete/ stop secreting hormones and from what mode of tranport
hypothalamic releasing or inhibitory hormones into the BLOODSTREAM
what hormones to anterior pituitary cells release
growth hormone, prolactin, thyroid stimulating hormone (TSH), ACTH, LH, FSH
what is a portal system and give 2 examples
2 venous capillary beds joined by a portal vein - hypophyseal portal system (transport hypothalamic hormones) and hepatic portal system
where is the pituitary gland located on the cranial floor
in pituitary fossa of sphenoid bone
where does the pituitary fossa lie within
sella turcica
what is the pituitary gland immediately inferior to
optic chiasm
what cranial nerves are close to the pituitary (5)
oculomotor (CNIII), trochlear (CNIV), ophthalmic trigeminal (CNV1), maxillary trigeminal (CNV2), abducens (CNVI)
what carries light from the eyes to the optic chiasm
right and left optic nerves (CNII)
what structures do light follow after the optic chiasm
right and left optic tracts
after the optic chiasm where does ‘light’ travel to
thalamus –> visual cortex in occipital lobe via optic radiation
what structures in the optic chiasm are compressed in a pituitary tumour
right and left nasal retina transmission
if the nasal retinas are compressed how does this affect the visual field
cannot see light coming from the temporal sides ie the peripheries
what visual defect does a pituitary tumour cause
bitemporal hemianopia
how would you surgically access the pituitary fossa
transcranial approach (under frontal bone) transsphenoidal (via nasal cavity and sphenoid sinus) - more common
what bones are in the nasal cavities (4)
inferior (hard palate - maxilla), vomer (nasal septum), perpendicular plate of ethmoid bone (superior nasal septum), cribriform plate of ethmoid bone (roff of nasal cavity)
how many nasal conchae are there and what do they create
superior conchae (ethmoid bone), middle nasal conchae (ethmoid bone) and inferior nasal conchae - create superior, middle and inferior nasal meatus which are spaces for airflow
how many nasal sinuses are there and what bones do they lie in
left and right FRONTAL sinus, right and left SPHENOID sinus (sphenoid bone but sometimes connected), right and left ETHMOID air cells (3 on each side), right and left MAXILLARY sinuses (12 sinuses in total)
what are paranasal sinuses lined by and what is their function
lines by mucous secreting resp mucosa - make mucosa and drain it to nasal cavity, make skull lighter, add resonance to voice
what are le fort fractures and how many classifications are there
fractures of the midface - type 1 - 3
what artery lies next to the optic nerve
internal carotid
what arteries come together to make the basilar artery
left and right vertebral artery
what is the diaphragm sellae
tough sheet of dura mater forming a roof over the pituitary fossa
what is the tentorium cerebelli
tough sheet of dura mater over the cerebellum of posterior cranial fossa with a gap for the brainstem
what is dura mater
lines entire cranial cavity
what are dural venous sinuses
venous channels that drain blood from the cranial cavity (incl brain) to the internal jugular veins
what sinuses surround the pituitary
cavernous and intercavernous sinuses
what arteries pass through the cavernous sinuses
internal carotids
where do dural venous sinuses drain into the jugular veins
jugular foraminae in the floor of the posterior cranial fossa
