The pituitary gland, also known as the master gland, is located in the sella turcica of the sphenoid bone. It consists of an anterior and posterior lobe. The anterior lobe secretes growth hormone and other hormones that regulate other endocrine glands. The posterior lobe stores and releases oxytocin and antidiuretic hormone produced by the hypothalamus. Diseases of the pituitary gland include hyperpituitarism due to overproduction of hormones and hypopituitarism due to underproduction. Pituitary tumors are also common and can cause hormonal imbalances or pressure effects.

1. Dr. Dinesh. M.G
Professor of Surgery
J.J.M.M.C.
Davangere

2. Pituitary gland
 Pituitary gland (master
gland) is situated in
pituitary fossa in the
middle cranial fossa
 The gland consists of two
lobes
 Anterior lobe
(adenohypophysis)
 Posterior lobe
(neurohypophysis)

3. Pituitary-anterior lobe
 It is an ectodermal derivative
formed from Rathke’s pouch
 The cells of anterior pituitary
secrete
 Growth hormone(GH)
 Prolactin
 ACTH & MSH(melanocyte
stimulating hormone)
 Thyroid stimulating
hormone(TSH)
 Follicle stimulating
hormone(FSH) & Leutinising
hormone(LH)
These functions are under the
indirect control of hypothalamus
through stimulatory & inhibitory
factors which reach the anterior
lobe through capillary flow

4. Pituitary-posterior lobe
 Develops as a diverticulum
from the floor of diencephalon
 Made of mainly interlacing
nerve fibres
 The nerve fibres contain
granules of neuro-secretory
material which secrete
 Vasopressin or antidiuretic
hormone(ADH)
 Oxytocin
Both these hormones are
produced by neuro-secretary
cells of hypothalamus but are
stored in cells of posterior
pituitary

5. Hormones of anterior pituitary
 Growth Hormone(GH)
 Regulation of body growth via liver by secreting growth factors
which help in chondrogenesis, skeletal growth, protein synthesis
& cell proliferation
 Prolactin
 Helps in milk production during lactation
 ACTH
 Regulates secretion from adrenal cortex of its corticosteroids
 TSH(Thyroid Stimulating Hormone)
 Regulates secretion of thyroid hormones from thyroid
 FSH & LH(ICSH)
 Also known as gonadotropic hormones
 Regulate production of estrogens and progesterone & induce
ovulation from ovaries
 Regulate production of testosterone from testis by acting on
interstitial cells of Leydig and help in maturation of sperms

6. Major endocrine organs

7. Hormones of posterior pituitary
 ADH(Anti diuretic hormone)
 Causes reabsorption of water from the renal tubules &
maintains the osmolality of plasma
 Oxytocin
 Acts on myoepithelial cells of breast helping propulsion of
milk during lactation
 Contraction of uterine muscles during delivery

8. Diseases of pituitary
 Hyperpituitarism
 Over secretion of one or more pituitary hormones
 A disease of anterior or posterior pituitary/ hypothalamus
 Hypopituitarism
 Decreased secretion of one or more pituitary hormones
 A disease of anterior or posterior pituitary/ hypothalamus
 Pituitary tumours

9. Hyperpituitarism
 For all practical purposes, hyper function of anterior
pituitary is due to a hormone secreting adenoma or rarely
a carcinoma
 Heperfunction of anterior pituitary
 Gigantism and Acromegaly
 Hyperprolactinemia
 Cushing’s syndrome

10. Gigantism and Acromegaly
 Occur because of sustained
excess of growth hormone
Gigantism occurs prior to
closure of epiphysis in pre-
pubertal boys and girls
 Excessive and proportionate
growth of child
 Considerable increase in height
and thickening of bone
Acromegaly occurs in adults
following cessation of bone
growth
 Enlargement of hands and feet
 Coarseness of facial features
 Prominent supraorbital ridges
 Prominent lower jaw producing
prognathism

11. Hyperpituitarism
Hyperprolactinaemia
 Excess production of prolactin
 In females it produces amenorrhea-
galactorrhea syndrome
 Infertility
 Milk secretion not related to pregnancy or
puerperium
 In males it may cause impotence
Cushing’s syndrome
 Excess secretion of ACTH
 Central or trunkal obesity with thin arms
and legs, moon face
 Wasting & thinning of skeletal muscle,
atrophy of skin and subcutaneous tissue
 Osteoporosis
 Hypertension . Diabetes mellitus
 Amenorrhoea, hirsuitism and infertility
 Insomnia, depression, confusion and
psychosis

12. Hyperpituitarism
 Hyperfunctioning of posterior pituitary
 Inappropriate release of ADH

13. Hypopituitarism
Hypofunction of anterior pituitary
 Occurs when more than 75% destruction of anterior lobe by
pituitary lesion or adjacent lesion
Two important syndromes in this are
 Panhypopituitarism
 Pituitary dwarfism: Severe deficiency of growth hormone
in children before growth is completed
 Pituitary adenoma, craniopharyngioma, infarction of pituitary
 Clinical features
 Normal mental age but proportionate retardation of bone growth
 Poorly developed genitalia
 Delayed puberty

14. Hypopituitarism
Hypofunction of posterior pituitary and hypothalamus
 Diabetes insipidus due to deficiency of ADH
 Polyuria(large volume with low specific gravity)
 Polydypsia

15. Pituitary tumours
 Account for 10-15% of all intra-
cranial tumours
 Majority are benign adenomas
 Carcinomas, primary or metastatic
are rare
 Clinical features are produced by
pressure effects or endocrine
dysfunction
 Pressure effects on optic
chiasma(bitemporal hemianopia)
 Dysfunction of cranial nerves
III, IV & VI
 Endocrine dysfunction
 Prolactinoma
 Corticotroph adenoma causing
Cushing’s syndrome
 Somatotroph adenoma causing
acromegaly or gigantism

16. Pituitary tumours
Investigations
 Eye examination
 Visual acuity
 Visual field examination
 Hormone assay
 Serum prolactin, FSH,
LH, TSH, Growth
hormone
 Serum and urinary free
cortisol
 MRI scan of pituitary
region

17. Pituitary tumours
Treatment
 Medical
 Prolactinoma is treated by bromocriptine
 Growth hormone secreting tumour is treated by octreotide
or dopamine agonist
 Surgical
 First line of treatment in corticotroph & thyrotroph adenoma
 For prolactinoma and growth hormone secreting adenomas
not responding to medical treatment

18. Pituitary tumours
 Trans-sphenoidal surgery
using operating
microscope.
 Nowadays endoscope is
being used instead of
operating microscope. The
approach is through nostril
and it cause minimal
lateral damage
 Radiotherapy is given in
case surgery is not
possible or for recurrence
after surgery

19. Thank you