Blood supply of Thyroid glands
Blood supply of thyroid glands
-2 sets of arteries -3 sets of veins
Superior thyroid vein
-accompanies superior thyroid artery -drains into internal jugular vein
inferior thyroid artery
-branch of thyrocervical trunk -runs upward/medially behind carotid sheath-reach posterior aspect of gland -gives off number of branches-ascending cervical, inferior laryngeal (accompanies recurrent laryngeal nerve to larynx) -Supplies mainly posterior/inferior aspect of gland -sends branches to parathyroid glands *as it passes medially behind thyroid gland, ITA becomes closely related to recurrent laryngeal nerve
inferior thyroid vein
-drain to brachiocephalic veins -sometimes unite into one channel which drains into left brachiocephalic vein
middle thyroid vein
-drains to internal jugular vein
superior thyroid artery
-gives off superior laryngeal artery (parallel to external laryngeal nerve) -reaches superior pole of thyroid gland -divides into anterior and posterior branches
Posterior branch of superior thyroid artery
-passes to posterior side -may anastomose with branches of inferior thyroid artery
Thyroid ima artery
-present in ~3-10% of population -arises from brachiocephalic trunk/arch of aorta -ascends on anterior surface of trachea to supply thyroid gland
Thyroid veins
-superior -middle -inferior
anterior branch of superior thyroid artery
-supplies anterior/superior surfaces of thyroid gland -anastomoses with counterpart from opposite side
