Thyroid, parathyroid and adrenals Flashcards
Which structure is the only complete cartilage ring in the neck?
Cricoid
Why is expansion of the thyroid dangerous?
if it expands, it expands posteriorly and crushes the trachea
Papillary cancer
Young people, stays local with good prognosis
Follicular cancer
Middle aged, spreads to lung and bone, usually good prognosis
Anaplastic cancer
Aggressive, very poor prognosis
red flags thyroid cancer
Rapid growth, cough, enlarged cervical LNs, tethering of lump to muscle
Treatment thyroid cancer
Thyroidectomy
Radioiodine therapy
External beam therapy
Chemotherapy
Why do you make more TSH when thyroid not working
Negative feedback - less T3/4 means more TSH made
Blood to thyroid
Superior thyroid artery, inferior thyroid artery
Which pouch are the superior parathyroid glands from?
Fourth pharyngeal pouch
Which pouch are the inferior parathyroid glands from?
Third pharyngeal pouch
Embryology of thyroid
- The thyroglossal duct pushes outwards from the pharyngeal floor
- It descends to the neck to form the thyroid gland
- The foramen caecum (midline punctum at junction of middle + posterior thirds of tongue) marks origin
- Lower end of duct persists to become gland whilst the rest disappears
- The thyroid gland is enclosed by pre-tracheal fascia which blends with laryngeal fascia so the thyroid moves upwards on swallowing
Malignant thyroids
Cancer can erode trachea/oesophagus/carotid sheath = stridor, dysphagia, haemorrhage
When will Horner’s syndrome arise?
Invasion of cervical sympathetic chain
Horners sx
- Affects one side of face only
- Persistently small pupil, differently sized pupils, little/delayed pupil opening, drooping of upper eyelid, elevation of lower eyelid, sunken appearance to eyes, little/no sweating on one side of face
