36 - Thyroid

Question 1

Which nerves innervate the thyroid?

Answer 1

Vagus

• superior laryngeal nerve
• recurrent (inferior laryngeal nerve)

Question 2

Which branch of the superior laryngeal nerve gives sensory innervation to the larynx and vocal cord?

Answer 2

internal

Question 3

What may happen when the external branch of the superior laryngeal nerve is damaged?

Answer 3

dysphonia- decreased voice volume

Question 4

Damage to the recurrent laryngeal nerve may cause: 3

Answer 4

vocal cord paralysis
ineffective cough/aspiration
airway obstruction if bilateral

Question 5

Which arteries supply the thyroid? 4

Answer 5

2 superior thyroid from the external carotid

2 inferior thyroid artery from the subclavian artery

Question 6

Which of the arteries supplying the thyroid, supply the parathyroid as well?

Answer 6

inferior thyroid artery

Question 7

Which veins drain the thyroid? 3

Answer 7

superior thyroid vein -> internal jugular vein
middle thyroid vein
inferior thyroid vein ->innominate & brachiocephalic

Question 8

Which cells make up the thyroid? which hormones do they produce?

Answer 8

follicular- T4/3

parafollicular (C cells)- calcitonin

Question 9

Describe the interaction between T3/4 and TRH/TSH:

Answer 9

T3/4 inhibit TSH and TRH- T3 is more potent

Question 10

Describe the interaction between dopamine/cortisol/somatostatin and TSH:

Answer 10

dopamine/cortisol/somatostatin inhibit TSH secretion from the hypophysis

Question 11

Serum thyroglobulin will be __ in thyrotoxicosis and __.

Answer 11

elevated

malignancy

Question 12

TPO antibodies suggest __/__.

Answer 12

Graves/Hashimoto

Question 13

Calcitonin is elevated in __ or __.

Answer 13

MEN2

medullary carcinoma

Question 14

Iodine mapping is used when we find a __ + __ TSH.
Warm= __hormones, usually __ and do not require __.
Cold=__ hormones, may be __.

Answer 14

nodule 
decreased
secreting
benign 
FNA
no
carcinogenic

Question 15

Warm mapping may suggest: 5

Answer 15

graves (homogenic)
toxic adenoma (focal)
toxic multi nodular goiter (multiple)
Hashitoxicosis 
TSH producing pituitary tumor

Question 16

Cold mapping may suggest: 4

Answer 16

subacute thyroiditis
iodine induced hyperthyroidism
thyroxine overdose (no radiation)
malignancy (decreased radiation)

Question 17

US may reveal nodules > _ mm. We can differentiate between __ and __.

Answer 17

3
benign
malignant

Question 18

Thyroid function tests:
euthyroid-\_\_
subclinical hypothyroidism-\_\_
overt hypothyroidism-\_\_
subclinical hyperthyroidism-\_\_
overt hyperthyroidism-\_\_

Answer 18

• euthyroid- normal TSG, T3/4
• subclinical hypothyroidism- elevated TSH, normal T3/4
• overt hypothyroidism-elevated TSH, decreased T3/4
• subclinical hyperthyroidism- decreased TSH, normal T3/4
• overt hyperthyroidism- decreased TSH, elevated T3/4

Question 19

What are the risk factors for thyroid malignancy? 6

Answer 19

• age (<30 , >60)
• men
• pre-exposure to iodine/radiation
• family Hx (MEN2, familial medullary carcinoma, PTC, Gardner syndrome, Cowden syndrome)
• normal thyroid function
• fast growing/rigid/hard/irregular characteristics

Question 20

נמחק שאר הפרק ואין לי כוח להשלים……

Answer 20

נמחק שאר הפרק ואין לי כוח להשלים……