Anatomy Flashcards
what are the three main parts of the brain?
cerebrum
cerebellum
brainstem
what are the three parts of the brainstem?
midbrain
pons
medulla oblongata
the spinal cord is the inferior continuation of what?
the brainstem (medulla oblongata)
the hypothalmus and the thalmus form what?
diencephalon
what does the diencephalon form?
the central core of the cerebrum
the diencephalon has connections to what parts of the brain?
right and left cerebral hemispheres
the midbrain
the hypothalmus is connecteed to the pituitary by what?
infundibulum or pituitary stalk
what is another anatomical term for the pituiatary?
hypophysis
how is the pituitary divided?
anterior and posterior pituitary
the pituitary is a midline structure found in which bone structure?
pituitary fossa of the sphenoid bone
the pituitary fossa lies within what?
the sella turcica
the pituitary gland lies immediatley inferior to what structure?
the optic chiasm
the optic chiasm is formed from what?
the right and left optic nerves (CNs II)
which cranial bone are the optic canals found in?
the sphenoid bone
the right and left optic tracts pass anteriorly/posteriorly from the optic chiasm
posteriorly
after passing throughthe optic chiasm where do axons from the optic tracts synapse?
the thalamus
after synapsing in the thalamus the next axons pass to the visual cortex via what?
optic radiation
the visual cortex is found where?
the occipital lobe
each retina is divided into what?
nasal and temporal retina
the retina contains what
photoreceptors: rods and cones
light from the temporal side of the visual fieid enters the nasal/temporal retina?
nasal
pituitary tumour causing midline compression of the optic chiasm would result in what?
disruption in transmission of action potentials from the nasal retina bilaterally
disruption of the transmission from the nasal retina would result in what
patient would loose the ability to see structures in the temporal side of the visual field
loss of vision in the temporal side of the visual field bilaterally is called what?
bitemporal hemianopia
what are the two surgical approaches to the pituitary?
transcranial approach
transsphenoidal approach
describe the transcranial surgical approach
subfrontal- under the frontal lobe
describe the transsphenoidal surgical approach
via nasal cavities and sphenoid sinus
what forms the roof of the nasal cavity?
the cribiform plate of the ethmoid bone
what forms the superior part of the nasal septum?
perpindicular plate of the ethmloid bone
what forms teh inferior part of the nasal septum?
the vomer
what are the nasal conchae also termed
turbinates
how are the nasal conchae of the lateral wall of teh nasal cavities divided?
superior nasal concha (of the ethmoid bone)
middle nasal concha (of the ethmoid bone)
inferior nasal concha
describe the paranasal sinuses
air filled spaces within the bones surroundign the nasal cavities
what lines the paranasal sinuses?
mucous secreting respiratory mucosa
what is the function of the paranasal sinuses?
make mucous and drain it into nasal cavities through ostia (bony holes)
reduce weight of skull
add resonance to voice
what are the four groups of paranasal sinuses?
frontal bone- frontal sinuses
maxillae- maxillary sinuses
ethmoid bone- ethmoidal air cells
sphenoid bone- sphenoid sinuses
the ethmoid air cells are further split into how many groups?
three groups between the nasal cavity and the orbit
the trasnsphenoidal transnasal surgical approach to the pituitary requires surgical fracture of which structures?
nasal septum
floor of the septum
roof of the sphenoid sinuses
in more complicated cases which Le Fort fracture approach to the nasal cavities provides better surgical access?
Le Fort 1 down- fracture approach
what lines the entirety of the cranial cavity internally?
dura mater
what is the name given to the tough sheet of dura mater stretched over the cerebellum within the posterioir cranial fossa?
the tentorium cerebelli
what is the name given to the tough sheet of dura mater that forms a roof over the pitutary fossa?
the diaphragm sellae
what within the dura mater drains blood from the cranial cavity?
dural venous sinuses
where do the dural venous sinuses drain into?
internal jugular veins at the jugular foraminae
Note: sinuses not histologically veins but function like them
where inthe cranial cavity are the jugular foraminae found?
the floor of the posterior cranial fossa
what connects the right and left cavernous sinuses to the pituitary?
the anterior intercavernous sinus
the pituitary gland is surrounded by what sinuses?
cavernous
intercavernous
which blood vessels pass through the cavernous sinuses?
the internal carotid arteries
the opthalmic artery is a branch of which major artery?
internal carotid artery
through what does the opthalmic artery enter the orbit?
the optic canal
the internal carotid artery enters the carotid canal in which cranial bone?
temporal bone