Thyroid Disorder

Question 1

How common is thyroid eye disease in Graves’ disease?

Answer 1

Affects approximately 25–50% of patients with Graves’ disease

Question 2

What is the underlying mechanism of thyroid eye disease?

Answer 2

Autoimmune inflammation of retro-orbital tissues, likely mediated by antibodies against the TSH receptor

Question 3

Which orbital tissues are primarily affected in thyroid eye disease?

Answer 3

Extraocular muscles and orbital fat

Question 4

What pathological changes occur in the extraocular muscles in thyroid eye disease?

Answer 4

Inflammation with glycosaminoglycan and collagen deposition causing muscle enlargement and fibrosis

Question 5

What is the most important modifiable risk factor for thyroid eye disease?

Answer 5

Smoking

Question 6

How does radioiodine therapy affect thyroid eye disease?

Answer 6

It may worsen or precipitate eye disease, particularly in Graves’ disease

Question 7

What medication reduces the risk of worsening thyroid eye disease after radioiodine?

Answer 7

Prednisolone

Question 8

What thyroid states may be present in patients with thyroid eye disease?

Answer 8

Euthyroid, hypothyroid, or hyperthyroid

Question 9

What is the most common clinical sign of thyroid eye disease?

Answer 9

Lid retraction

Question 10

What causes lid retraction in thyroid eye disease?

Answer 10

Sympathetic overactivity leading to overaction of the levator palpebrae superioris and Müller’s muscle

Question 11

What appearance does lid retraction produce?

Answer 11

A “staring” appearance

Question 12

What is the most specific clinical sign of thyroid eye disease?

Answer 12

Exophthalmos

Question 13

What causes exophthalmos in thyroid eye disease?

Answer 13

Forward displacement of the globe due to inflammation and oedema of extraocular muscles and orbital fat

Question 14

What ocular surface feature is commonly seen due to orbital inflammation?

Answer 14

Conjunctival oedema

Question 15

How does thyroid eye disease affect eye movements?

Answer 15

Causes ophthalmoplegia due to extraocular muscle involvement

Question 16

Why do patients with thyroid eye disease develop dry, sore eyes?

Answer 16

Incomplete eyelid closure leading to excessive corneal exposure

Question 17

What is the most important non-pharmacological intervention in thyroid eye disease?

Answer 17

Smoking cessation

Question 18

What is first-line supportive treatment for exposure symptoms?

Answer 18

Topical lubricants

Question 19

Which drug class is used for moderate to severe active disease?

Answer 19

Systemic corticosteroids

Question 20

What additional treatment options may be used in severe disease?

Answer 20

Radiotherapy or surgery

Question 21

What is the most common complication of thyroid eye disease?

Answer 21

Exposure keratopathy

Question 22

Why does exposure keratopathy occur in thyroid eye disease?

Answer 22

Lid retraction and proptosis cause excessive corneal exposure and tear film disruption

Question 23

What symptoms suggest exposure keratopathy?

Answer 23

Foreign body sensation, pain, photophobia, dryness

Question 24

What is the most serious complication of thyroid eye disease?

Answer 24

Optic neuropathy

Question 25

How does optic neuropathy occur in thyroid eye disease?

Answer 25

Compression of the optic nerve at the orbital apex by enlarged extraocular muscles

Question 26

What visual features suggest optic neuropathy?

Answer 26

Reduced visual acuity, impaired colour vision, visual field defects

Question 27

Why is optic neuropathy an emergency?

Answer 27

Risk of permanent vision loss without urgent treatment

Question 28

What causes diplopia in thyroid eye disease?

Answer 28

Restrictive strabismus from fibrosis and enlargement of extraocular muscles

Question 29

Which visual symptom mandates urgent ophthalmology referral?

Answer 29

Unexplained deterioration in vision

Question 30

Which colour vision change is concerning in thyroid eye disease?

Answer 30

Reduced intensity or quality of colour vision

Question 31

What globe abnormality is an ophthalmic emergency in thyroid eye disease?

Answer 31

Globe subluxation (“eye popping out”)

Question 32

Which corneal finding requires urgent review?

Answer 32

Corneal opacity or visible cornea when eyelids are closed

Question 33

Which fundoscopic finding is a red flag?

Answer 33

Optic disc swelling