2.1 Thyroid Eye Disease I

Question 1

What is Graves disease?

Answer 1

A type of autoimmune disorder that leads to over activity of the thyroid gland and is termed hyperthyroidism. As a result the thyroid gland enlarges and excess hormones increase the metabolism.

Question 2

What are symptoms of Graves disease (hyperthyroidism)?

Answer 2

• Weight loss – despite increased appetite
• Anxiety, restlessness, tremors, irritability, insomnia.
• Heat intolerance
• Chest pain, shortness of breath
• Muscle weakness
• Goitre (enlarged thyroid gland)

Question 3

What are the treatments available for Graves disease?

Answer 3

• Medicine – thionamides (stop the thyroid gland producing excess hormones). Main types used are carbimazole and propylthiouracil. Patients usually need to take the medication for 1 to 2 months before they notice any benefit.
• Radioactive iodine treatment – Used to destroy cells in the thyroid gland thus reducing the amount of hormones it can produce. Patients consume a drink or capsule containing iodine and a low dose of radiation which is absorbed by the thyroid, most people only require a single treatment. It can take a while for full benefits to be felt and so patients may need to take medicine for a short time.
• Surgery – thyroidectomy

Question 4

What are some side effects of medical treatment with Graves disease?

Answer 4

• Feeling sick
• Headaches
• Aching joints
• Altered taste
• Upset stomach
• Itchy rash
• Agranulocytosis (sudden drop in blood cell count) which can compromise immunity – LESS COMMON

Question 5

What precautions need to be considered in radioactive iodine treatment?

Answer 5

• Avoid prolonged close contact with children and pregnant women for a few days or weeks
• Women should avoid getting pregnant for at least 6 months
• Men should not father a child for at least 4 months
• Radioactive iodine treatment is not suitable for women who are pregnant or breastfeeding. Its also not suitable if your overactive thyroid is causing severe eye problems (TED).

Question 6

When would a thyroidectomy be a good consideration in Graves disease?

Answer 6

o The thyroid gland is severely swollen because of a large goitre
o There are severe eye problems caused by an overactive thyroid
o The patient is unsuitable for other, less invasive treatments.
o The symptoms return after trying other treatments.

Question 7

What is a lifelong implication of a thyroidectomy?

Answer 7

The patient will need to take thyroid medication (eg levothyroxine) for the rest of their life to make up for not having a thyroid gland.

Question 8

What are the signs of TED?

Answer 8

• Upper lid retraction – accentuated by proptosis and in attempted up gaze when the IR are tight.
• Reduced frequency of blinking
• Lid lag on down gaze
• Staring appearance
• Conjunctival injection – (red eyes) sometimes over the site of rectus muscle insertion
• Chemosis – Swelling on the conjunctiva
• Oedema of the lids – build-up of fluid
• Proptosis – protrusion of the eye

Question 9

What are the symptoms of TED?

Answer 9

• Diplopia
• Blurred vision/visual loss
• Epiphoria
• Grittiness of eyes
• General ocular discomfort/pain
• Photophobia

Question 10

What are the strabismic complications associated with TED?

Answer 10

• The most commonly effected muscle is the inferior rectus (IR), then the MR, SR and LR.
• Limited elevation is most common but there may also be limited abduction, limited depression, and limited adduction.

Question 11

What are the ocular motility complications with TED?

Answer 11

• Mechanical problems (duction = version)
• Limitations can be;
  o Direct – Limitation of OM when gaze is directed away from ‘the leash’ – tight or shortened muscle.
  o Indirect – Limitation of OM when the gaze is directed towards ‘the leash’ – trauma

Question 12

What causes vision loss in TED?

Answer 12

• Due to an increase in orbital pressure with optic nerve compression
• From corneal exposure from marked proptosis with exposure keratitis
• From induced refractive error

Question 13

What are the different classifications of TED?

Answer 13

• VISA – Disease grade = score out of 20
  o (V)ision – optic neuropathy
  o (I)nflammation/congestion
  o (S)trabismus/motility
  o (A)ppearance/exposure
• EUGOGO
• NOSPECS
• Uddin phenotypes
  o Congestive (active inflammatory)
  o ‘White eye’ expansion
  o ‘Hydraulic’ apex
  o ‘White eye’ apex
  o Cicatricial active
  o Cicatricial passive