Thyroid Eye Disease

Question 1

What are the 2 stage of pathogenesis in thyroid eye disease?

Answer 1

• Inflammation of EOMs:
  o Enlargement up to 8x
  o Fibrosis - scarring
• Inflammatory cellular infiltration:
  o Increase in volume of orbital structures
  o Elevation of IOP

Question 2

What are the 2 stages of disease development in thyroid eye disease?

Answer 2

• Congestive:
  o Acute phase
  o Red, painful eyes
  o 10% have long-term complications
• Fibrotic:
  o Long term, more chronic phase
  o White and painless
  o Scarring
  o Motility defect

Question 3

What are the 5 clinical manifestations of Thyroid Eye Disease?

Answer 3

• Soft tissue involvement
• Lid retraction
• Proptosis
• Optic neuropathy
• Restrictive myopathy

Question 4

What is Graves’ Disease?

Answer 4

immune system disorder, systemic disorder that results in overproduction of thyroid hormone – hyperthyroidism. One of most common causes of hyperthyroidism

Question 5

What is thyroid eye disease?

Answer 5

an element of Graves disease. If px has ocular signs & symptoms of thyroid eye disease & does not tell you they have Graves disease, liaise w/ px’s GP to pursue that process

Question 6

Describe the symptoms, signs and treatment of soft tissue involvement in thyroid eye disease?

Answer 6

• Symptoms:
  o General dry eye symptoms
  o Grittiness
  o Photophobia
  o Lacrimation – tears can’t drain normally
  o Discomfort
• Signs:
  o Hyperaemia/conjunctival injection
  o Swelling – conjunctiva (chemosis), eyelids
  o Superior limbic keratoconjunctivitis – dryness of eye, particularly in superior limbus region because of the soft tissue involvement
  o Dry eye
• Treatment:
  o Do they have the systemic condition? Liaise w/ GP
  o Treat conditions that are evident: treat the dry eye condition
   If more severe or outwith optom’s scope of practice then refer

Question 7

Describe lid retraction in thyroid eye disease?

Answer 7

• Occurs in 50% with Graves disease
• Pathogenesis:
  o Fibrotic contracture of levator muscle – pulls upper eyelid up
  o Secondary overaction of levator-superior rectus complex in response to fibrosis of inferior rectus
   Levator is connected to superior rectus
  o Humorally-induced overaction of Muller muscle – contracting eyelid
• Symptoms/signs:
  o Upper lid higher than normal, lower lid lower than normal
• Treatment:
  o Mild -> none, may spontaneously resolve
  o Surgery considered if stable (lid retraction present but has not changed in while)
  o Treat the associated dry eye – due to over exposure of ocular surface as result of lid retraction (see the dry eye CMG)

Question 8

Describe proptosis in thyroid eye disease?

Answer 8

• Congestion of cells pushing eye forward
• Axial – pushed forward along horizontal axis
• Unilateral or bilateral
• Symmetrical or asymmetrical
• Exposure keratopathy
• Corneal ulceration
• Infection – if corneal ulceration not treated
• Treatment:
  o Treat the dry eye (see dry eye CMG)
  o Treat the corneal problem – bacterial keratitis would be treated by hospital (see keratitis CMGs)

Question 9

Describe restrictive myopathy in thyroid eye disease?

Answer 9

• 30-50% have ophthalmoplegia (may be permanent)
• IOP may increase when moving eye or in primary position – IOP increases due to restriction of eye movement
• All of EOMs may be affected  diplopia
• In order of most commonly affected: Elevation; Abduction; Depression; Adduction
• Treatment:
  o Referral for surgery or bolulamin toxin (botox) – to help with diplopia

Question 10

Describe optic neuropathy in thyroid eye disease?

Answer 10

• Congestion & inflammation around ONH then will get optic neuropathy
• Uncommon but serious
• Signs:
  o Loss of vision
  o RAPD – if monocular or asymmetrical
  o Field defects
  o Increased IOP
  o Usually normal appearance of disc – retrobulbar condition (affects further back in optic nerve)
• Treatment:
  o V serious as optic nerve becoming compressed
  o Ophthalmologist treats with steroids to reduce inflammation