Thyroid Eye Disease

Question 1

Normal control of thyroid

Answer 1

• thyrotropin releasing hormone is produced by the hypothalamus
• acts on the anterior pituitary gland, releasing TSH

Question 2

Abnormal control of thyroid

Answer 2

• hyperthyroidism in graves
• targets the TSH receptor and mimics the effect of normal TSH resulting in overstimulation of the thyroid gland
• swelling of the gland
• overproduction of T4 and T3

Question 3

Causes of thyroid eye disease

Answer 3

• Graves’ disease
• thyroiditis
• toxic multi nodular
• toxic thyroid nodule
• self administered thyroid hormones

Question 4

Pathophysiology of TED

Answer 4

• acute/active inflammatory
• late/inactive phase

Question 5

Features of the active phase

Answer 5

• connective tissue inflammation
• activation of EOM fibroblasts
• increased orbital volume
• these then attract water
• inflammatory myopathy resulting from the autoimmune process

Question 6

Features of connective tissue inflammation

Answer 6

• redness
• mild ocular discomfort
• preorbital swelling
• pain or motility

Question 7

5 signs of TED

Answer 7

• soft tissue involvement
• restrictive myopathy
• lid retraction
• proptosis
• optic neuropathy

Question 8

Other signs of TED

Answer 8

• chin elevation
• hypophoria/tropia usually first deviation
• with/without head turn
• enlarged fusion range
• raised iop on elevation/attempted elevation

Question 9

Typical order of EOM imitation

Answer 9

• inferior rectus
• medial rectus
• superior rectus
• lateral rectus

Question 10

Features of soft tissue inflammation

Answer 10

• periorbital swelling
• conjunctival swelling
• conjunctival injection
• reduced tear production

Question 11

Signs of optic nerve compression in TED

Answer 11

• loss of VA
• RAPD
• colour vision defects
• possible optic atrophy
• pinhole to make sure not refractive
• visual field defects
• mild or no disc swelling
• VEP showing reduced amplitude

Question 12

Inactive phase features

Answer 12

• cicatricial phase
• reduction in proptosis and swelling
• fibrosis and muscle contraction
• corneal exposure due to retraction of lids

Question 13

Systemic symptoms of hyperthyroidism

Answer 13

• weight loss
• sweating
• lethargy
• tremour
• intolerance of heat
• reduced tolerance of cold
• increased appetite
• increased heart rate