Anatomy of the Pituitary Gland Flashcards
What do the thalamus and hypothalamus make up?
Diancephalon
Where in the brain can the diencephalon be found?
central core of cerebrum
Connects to R+L hemispheres and midbrain
What 3 areas make up the brainstem?
Midbrain
Pons
Medulla (oblongata)
What connects the hypothalamus to the pituitary?
the infundibulum
What division of the pituitary gland is connected to the hypothalamus?
Posterior pituitary
What embryological structure eventually develops into the anterior pituitary gland?
Rathke's pouch From Ectoderm (=> glandular tissue)
What embryological structure eventually forms the posterior pituitary?
Infundibulum
From NEURAL ectoderm (=> neural tissue)
What tumour is commonly found in the anterior pituitary gland?
Adenoma
What 3 sections make up the anterior lobe of the pituitary gland?
Pars distalis
Pars tuberalis
Pars intermedia
What section makes up the posterior pituitary
Pars nervosa
Where is the pituitary gland located in the brain?
midline structure in pituitary fossa of sphenoid bone
What does the pituitary gland lie immediately inferior to?
Optic chiasm
What makes up the optic chiasm?
right & left optic nerves (CN II)
Light entering what part of the retinae causes it to cross to the opposite occipital lobe?
Nasal Retinae
=> light coming from temporal visual field
If a tumour grows from the pituitary and interrupts conduction at the optic chiasm, what can this cause?
Loss of vision in the temporal fields
=> Bitemporal Hemianopia
How can a pituitary tumour be removed surgically?
Transcranial approach (subfrontal–under frontal lobe) Transsphenoidalapproach (via nasal cavities & sphenoid sinus)
What bone is responsible for forming the roof of the nasal cavity?
Cribiform plate of the ethmoid bone
What parts of the ethmoid bone are found above the hard palate
Superior, Middle and Inferior nasal concha
What are the air spaces around the ethmoid bone called?
Paranasal sinuses
What bones must be broken for a transsphenoid/transnasal approach?
surgical fracture of the nasal septum and the floor (septum) & roof of the sphenoid sinus(es)
What fracture can be more useful for surgical approach in more complicated cases
Le Fort Fracture 1
What is the Dura Mater?
thick membrane adherent to the internal aspects of all the bones of the cranial vault
What is similar to the dura mater but covers the cerebellum?
Tentorium cerebelli
** Has central gap to permit the brainstem to pass through**
What is the name given to the dura mater found over the pituitary fossa
Diaphragm sellae
What are the dural venous sinuses?
- Venous channels within the dura mater
- drain most of the venous blood from the cranial cavity (including the brain) into internal jugular veins
What structure passes through the cavernous sinuses?
Internal carotid arteries `
