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1. Purpose: To
apply the
knowledge
gained in
Anatomy and
Physiology in
the diagnosis
of some
vision and
eye disorders
Applied Ocular
Anatomy
&
Physiology

2. PITUITARY DISORDERS
Pituitary tumours
Pituitary tumors are responsible for most hormone abnormalities involving the
pituitary gland (PG) – Adenoma
3 histological types of pituitary tumour, all “adenomas”.
Most (80% are benign)
The pituitary lies directly below the optic chiasma
Pituitary tumours tend to grow upwards – OCULAR COMPLICATIONS
A pituitary tumor can cause the (PG) to produce too much or too few
hormones, which can cause problems in the body.
Pituitary tumours may produce illness by:
1.Local pressure related to size and location
2.Secretion of hormones in unusual amounts
3.Hypopituirism

3. ACROMEGALY/GIGANTISM
Rare -hypersecretion of growth hormone (GH) by Somatotrophs ( a growth
hormone achieves development of the human body). These are released
by the Pituitary Gland
Usually forms a pituitary adenoma.
Affects - 20 and 40 years of age.
Acromegaly: hypersecretion during adulthood – overgrowth of bone and
tissue
Gigantism: hypersecretion during childhood – induced skeletal (bone) growth
still maintaining normal shape and proportion

4. Clinical Features
Increase in size of skull
Thick, spade shaped fingers, increasing shoe size and vertebral enlargement
Enlarged tongue, heart, liver and thyroid.
Headache (the dura is stretched as skull enlarges).
Voice deepens.
Hypertension , heart failure, diabetes, joint pain, proximal muscle weakness may
also develop.

5. ACROMEGALY/GIGANTISM
Management:
Destruction of the tissue producing the excess
hormone.
The choice between surgery, external irradiation and
radioactive implant depends on the age and health of
the patient.
Untreated, the life expectancy of a person with
acromegaly is halved.
Bromocriptine reduces GH levels -useful additional
treatment.

6. Hyperprolactinaema
Stimulates breast development and milk production in women.
Commonest condition caused by pituitary dysfunction
Patients usually presents to the gynaecologists in the guise of
menstrual disturbance, and infertility.
Prolactin is a Hormone secreted by the Pituitary gland for production of
milk. It goes with the name lactose. It is found in both male and
females.
Increased blood prolactin levels also produce acne, galactorrhoea,(milk
discharge from nipples) ↓ libido and (in males) impotence.

7. Hyperprolactinaema
Other causes of ↑ prolactin are:
Pregnancy, breast feeding, stress and sleep
Drugs- phenothiazines and haloperidol (used in control of psychosis),
methyldopa and oestrogens.
Chronic renal failure
Management:
Depends on underlying cause.
Bromocriptine or Cabergoline
Surgery +/– radiation
These tumours are very slow-growing and sometimes require no
treatment

8. Cushing Syndrome
Hypersecretion of cortisol
• Presents with:
– Hypertension
– Obesity
– Diabetes
– Skin marks (striate)
– Excess body and facial hair
– Alterations in mental function

9. Posterior Pituitary Hyperfunction
• Excessive H20 retention
• Oedema
• Weight gain
• Hypertension

10. Hypopituitarism
Under-activity of the pituitary gland.
Aetiology:
Surgery.
Radiation.
Adenoma.
Post partum (after giving birth) haemorrhage.
Secondary malignancy.

11. Anterior Pituitary Hypofunction
• Failure of pituitary secretion may affect one or several
hormones: Lack of:
– TSH: Hypothyroidism
– Prolactin: Hyperprolactinemia
– ACTH ( adrenocorticotropic Hormone)
– Gonadotrophin

12. Anterior Pituitary Hypofunction:
Hypoprolactinemia
Clinical features:
Inability to lactate
Children → “Peter Pan” dwarfism (look young when old).
Adults → A variety of hormone problems including menstrual
disturbance, adrenal insufficiency, hypothyroidism and decreased
body hair.
Treatment:
 Hormone replacement (e.g. “the pill”, cortisone, thyroxine).

13. Thyroid disease
The thyroid gland and the pituitary gland work together.
The pituitary “master gland,” - makes, stores, and releases thyroid-
stimulating hormone (TSH)- tells the thyroid how much hormone
triiodothyronine (T3) thyroxine (T4) .
Iodine from blood (diet) + tyrosine (amino acid) by action of TSH produce
T3 and T4
Thyroid hormones affect every cell and all the organs of the body.

14. Function of T3 +T4
1.Controls the rate of metabolism. : ↑ basal metabolic rate (BMR)
2.Slows down or speed up your heartbeat.
3.Raises or lowers your body temperature.
4.Change how fast food moves through your digestive tract.
5.Affect muscle strength.
Too much thyroid hormone speeds things up and too little thyroid hormone
slows things down.

15. Hyperthyroidism
Excess circulating T3 +T4
(Hyperthyroidism) causes Thyrotoxicosis
(clinical syndrome , excess blood levels of
thyroid hormone)
Clinical presentation:
• Nervousness
• Tiredness
• Palpitations
• ↑ appetite
• ↓ weight
• Excessive sweating
• Heat intolerance

16. Types
of Thyroid
lesions
Graves Disease :
•Toxic Nodular Goitre < 10%
•Toxic Adenoma < 5%
•Acute or painless
thyroiditis: inflammation
of the thyroid gland due
either to virus or taking
too much of thyroid
hormone in tablet form

17. OCULAR MANIFESTATIONS
Autoimmune attack specifically on the eye muscles and
connective tissues within the socket
-tissues contain protein like those found in the immune system
Causes inflammation
• Swelling of muscles and surrounding tissue
• Restricted eye movement
• Pain
• Eyes bulge forward – Proptosis
• 2° complications
• May impinge on the Optic Nerve
• Blurred vision

18. Hypothyroidism
Ocular signs
 Usually, rare
Loss of lateral 1/3 of eyebrow
Peri-orbital oedema
1.Decrease TSH - increase in mucus like protein deposit in the deeper skin
2.Resolves with treatment
Ptosis
1.Decrease TSH decreases nerve stimulation of eyelids - drooping
Lenticular opacities
KCS

19. Adrenal Glands
It’s the structure on top of kidney
Adrenal gland:
 Adrenal medulla secretes adrenaline and noradrenaline
(catecholamines).
 Adrenal cortex produces 3 steroid hormones (corticosteroids):
1. Glucocorticoids (cortisol) which raise blood sugar, antagonize
insulin, facilitate the action of catecholamines on the heart and
blood vessels, supress the inflammatory response, break down
protein, reduce the white cell count and cause sodium retention and
potassium loss.
2. Mineralocorticoids (aldosterone) which cause sodium retention
and potassium loss.
3. Repro. hormones-testosterone and oestrogens.

20. Adrenal Disorders
Disorders of the adrenal cortex
Clinical features include:
• Moon face
• Acne
• Fat body ± “buffalo” hump on back
• Muscle weakness
• Purple stretch marks (striae) on abdomen, thighs and buttocks (“normal” stretch marks are pink)
• Easy bruising
• Osteoporosis (leading to back ache and, sometimes, vertebral collapse)
• Diabetes, Hypertension,
• Sodium retention, Potassium loss
• Kidney stones,
• Mental disturbance,
• Masculinization of females

21. Disorders of the adrenal medulla
Neuroblastoma - Cancer of immature nerve cells arising from the adrenal gland,
nerve ganglia or the neck. This causes abdominal pain, diarrhea or constipation,
lumps of tissue under the skin, wheezing and weight loss.
Pheochromocytoma
• Tumour mainly of adrenal medulla or extra-adrenal tumour around
sympathetic ganglia.
• Produces excess adrenaline.
• Remember: adrenaline maintain normal BP and helps us cope with stressful
situations
• Clinical manifestation reflect:
• elevated circulating catecholamines.
• 90% of these patients have dramatic hypertension in the region
220/150mHg.
• May present retinal and cerebellar haemangiomas

22. Symptoms of Medulla disorder
headaches,
sweating,
racing heart( tachycardia and palpitations),
nausea,
weight loss
heat intolerance
Surgery is definitive treatment