Endocrine Flashcards
Development of upper parathyroid glands
Arise from fourth branchial arch
Usually found at the back of the thyroid above the inferior thyroid artery
Development of the lower parathyroid glands
Arise from the third branchial arch
Usually in association with thyrmus
Level of the thyroid glands
Lie on front of trachea and larynx at C5-C7
Superior thyroid artery
Branch of external carotid artery
Inferior thyroid artery
Branch of thyrocervical trunk of subclavian artery
As the inferior thyroid artery appraoches the galdn it normally passes in front of the recurremt laryngeal nerve
Lymphatic drainage of the thyroid
Pretracheal and mediastinal nodes
Veins of the thyroid
Superior
Middle
Inferior
.. thyroid veins
S+M into the internal jugular and ITV drains into brachiocephalic
Innervation of the intrinsice muscles of the larynx
Recurrent laryngeal nerve supplies all of them except Cricothyroid (exterior branch of superior laryngeal)
Innervation of the cricothyroid muscles
External branch of the superior laryngeal nerve
Innervation providing sensation above the vocal cords
Internal branch of the superior laryngeal nerve
Innervation providing sensation below the vocal cords
Recurrent laryngeal nerve
Non-toxic multinodular goitre
Multiple nodules
Caused by iodine deficiency
If biochemistry normal, no need for radio-isotype uptak e scan
Mx: Thyroidectomy and replacement
Can become toxic: a long-standing non-toxic goitre develops hyperactive nodule(s) that function independently of TSH levels
Management of hashimoto’s
Replacenebt thyroxine
Thyroidectomy seldom needed and carries higher riusk of recurrently laryngeal nerve injury due to firmness of gland
Firm painless swelling and tracheal compression
Riedel’s thyroiditis
Mx: Aspirated cysts that do not re-fill with negative cytology
OP follow-up
Residual aspirate or blood-stained aspirare
Suspect Papilllary carcinoma