Histology of the Pituitary Gland Flashcards
Where is the pituitary gland in the brain?
In the sella turcica of the sphenoid bone
What is the superior border of the pituitary gland?
Diaphragma sellae and hypothalamus
What is the inferior border of the pituitary gland?
Sella turcica
What is the lateral border of the pituitary gland?
Cavernous sinus
What is the anteroinferior border of the pituitary gland?
Sphenoid sinus
What is the anterosuperior border of the pituitary gland?
Optic chiasm
What arteries run laterally to the pituitary gland?
Internal carotids
What is the large sinus situated inferiorly to the pituitary gland?
Sphenoid sinus
What is the clinical relevance of the proximity of the internal carotids to the pituitary gland?
Pituitary adenoma may impinge on internal carotids, causing neurological ssx
What is the CN that sits superiorly to the carotid artery at the level of the pituitary?
CN III
What is the CN that sits laterally to the carotid artery at the level of the pituitary?
CN IV
What is the CN that sits inferior to the carotid artery at the level of the pituitary?
CN VI
What arteries supply the anterior cortical border zone (anterolateral regions) of the brain?
ACA and MCA
What arteries supply the internal border zone (medial region) of the brain?
ACA
MCA
What arteries supply the posterior cortical border zone (posterolateral regions) of the brain?
MCA and PCA
How is access gained to the pituitary during surgery?
Go through the nostrils and break through the sphenoid sinus
What is primary empty sella syndrome? What is the usual presentation?
Arachnoid mater invades the sella turcica d/t defect in the sellar diaphragm, compressing the pituitary gland posteriorly, and widening the superior opening for the infundibulum
Usually asymptomatic
What is secondary empty sella syndrome?
Secondary ESS is the result of the pituitary gland regressing within the cavity after an injury, surgery, or radiation therapy. Individuals with secondary ESS due to destruction of the pituitary gland have symptoms that reflect the loss of pituitary functions, such as the ceasing of menstrual periods, infertility, fatigue, and intolerance to stress and infection.
What are the three portions of the anterior pituitary (in order, from superior to inferior)?
Pars tuberalis
Pars intermedia
Pars distalis
What are the two portions of the posterior pituitary?
Infundibular stalk
Pars nervosa
What is the pars tuberalis?
The “collar” of the anterior pituitary that wraps around the infundibulum
What is the neurohypophysis?
Posterior pituitary
What is the adenohypophysis?
Anterior pituitary
From what layer of the developing fetus does the anterior pituitary gland form? Posterior?
Anterior = oral ectoderm Posterior = Neuroectoderm
What is Rathke’s pouch?
a depression in the roof of the developing mouth in front of the buccopharyngeal membrane. It gives rise to the anterior pituitary (adenohypophysis).
What part of the developing brain gives rise to the posterior pituitary?
Diencephalon
What is the clinical significance of remnants of Rathke’s pouch?
The development of a craniopharyngioma