ENT - The Thyroid Gland Flashcards
1
Q
Describe the arterial supply to the thyroid gland. Which structures are closely associated?
A
- superior thyroid artery (1st br of external carotid a.) - associated with external laryngeal n.
- inferior thyroid artery (br of thyrocervical trunk) - associated with recurrent laryngeal n.
- +/- variant thyroid ima artery
2
Q
A 50yo lady presents with an enlarged thyroid gland. What is your differential diagnosis?
A
Goitre only:
- multinodular goitre
- iodine-deficiency (simple goitre)
- thyroid cancer
Goitre + metabolic dysfunction:
- Grave’s disease (simple goitre)
- toxic multinodular goitre
- toxic adenoma
- Hashimoto’s disease
3
Q
A 50yo lady presents with a single thyroid nodule detected on USS. What Ix should be performed?
A
- TFTs
- USS-guided FNA
- if any diagnostic doubt: diagnostic hemithyroidectomy
4
Q
What is your differential diagnosis for a single thyroid nodule?
A
- non-neoplastic: colloid or cystic
- benign follicular adenoma
- malignant neoplasms:
- papillary (70%)
- follicular (20%)
- medullary (5%, from parafollicular C cells): usually in MEN, increased calcitonin with normal calcium
- anaplastic (usually in elderly females): rapid painful enlargement of thyroid, airway/voice/swallowing problems, poor prognosis
5
Q
What is the usual Tx for papillary thyroid cancer?
A
- total thyroidectomy +/- neck dissection
- +/- post-op radioiodine
- lifelong thyroid hormone replacement at TSH-suppressing doses
6
Q
Suggest possible complications of thyroid surgery.
A
- post-op haemorrhage
- airway obstruction:
- secondary to haemorrhage (most frequent cause in 1st 24hrs)
- secondary to bilateral vocal cord palsy
- vocal cord palsy: due to RLN palsy causing hoarseness if unilateral or aphonia + airway obstruction if bilateral
- hypocalcaemia due to parathyroid trauma or devascularisation: presents acutely at 24-48hrs as laryngeal stridor + airway obstruction, QT prolongation + cardiac arrest
- post-op infection