Pituitary Gland

Question 1

Describe relations of pituitary gland

Answer 1

A, tuberculum sella
P, dorsum sella separating it from pons
S, optic chiasm & diaphragma sella
I, body of sphenoid & sphenoidal air sinus
On either side, cavernous sinus with its contents

Question 2

The largest part of pituitary is…..while the part that encircles infundibulum is……

Answer 2

Pars distalis
Pars tuberalis

Question 3

Describe blood supply of pituitary gland

Answer 3

Art:
1. Superior hypophyseal arteries arise from 4th part of ICA, supply ventral part of hypothalamus which arise from hypothalamic hypophyseal portal vein to adenohypophysis
2. Inferior hypophyseal arteries arise from 3rd part of ICA form a ring around infundibulum
Ven:
Cavernous sinus

Question 4

ADH is secreted by…..while oxytocin by……and releasing hormones by……

Answer 4

Supraoptic n.
Paraventricular n.
Infundibular/arcuate n.

Question 5

Enumerate effects of pituitary tumors

Answer 5

Upward pressure on optic chiasma leading to bitemporal hemianopia
Downward pressure leading to ballooning of sella
Lateral pressure on cavernous sinus, eye congestion & diplopia
Endocrine disturbance

Question 6

Describe development of pituitary

Answer 6

2 sources:
1. Upward growth from the ectodermal roof of stomodeum (hypophyseal diverticulum or Rathke’s pouch, from surface ectoderm)
2. Downward growth from neuroectoderm of the floor of diencephalon (neurohypophyseal diverticulum, infundibular process)

Question 7

Pituitary cleft is…….located between……

Answer 7

Remnant of Rathke’s pouch
Pars distalis & pars intermedia

Question 8

Mention an anomaly of pituitary gland with explanantion

Answer 8

Pharyngeak hypophysis & craniopharnygioma
Remnant of the stalk of Rathke’s pouch in the roof of oropharynx. Craniopharngioma may arise leading to hypopituitarism