Vessel
Thyroid ima artery
Variable pretracheal artery supplying the lower thyroid
High-yield
Its pretracheal position matters more clinically than memorizing one prevalence. It may supply the isthmus or a lower lobe, especially when another thyroid artery is small or absent.
Overview
A thyroid ima artery is an additional or replacement thyroid supply found in a minority of people. It commonly arises from the brachiocephalic trunk and ascends in front of the trachea. Its origin, caliber and contribution to the gland vary.
Reference facts
- Origin
- Most often the brachiocephalic trunk; documented alternatives include the aortic arch, common carotid, internal thoracic and subclavian arteries.
- Course
- Ascends anterior to the trachea, usually near the midline, toward the isthmus or lower thyroid.
- Branches
- Variable thyroid branches, sometimes with branches to the trachea or neighboring structures.
- Supplies
- Part of the thyroid and occasionally adjacent tissues; it may supplement or partly replace another thyroid artery.
- Drains to
- Blood from its thyroid territory returns through the thyroid venous network, often inferior thyroid veins. The artery itself does not drain into those veins.
Clinical correlation
This vessel is one possible source of unexpected bleeding during thyroid or anterior airway procedures. A lower neck location cannot be assumed to be free of a substantial artery.
Frequently asked questions
Where does the thyroid ima artery originate?
Most often the brachiocephalic trunk; documented alternatives include the aortic arch, common carotid, internal thoracic and subclavian arteries.
What does the thyroid ima artery supply?
Part of the thyroid and occasionally adjacent tissues; it may supplement or partly replace another thyroid artery.
Where does blood from the thyroid ima artery go?
Blood from its thyroid territory returns through the thyroid venous network, often inferior thyroid veins. The artery itself does not drain into those veins.
What are the branches of the thyroid ima artery?
Branches of the thyroid ima artery include the variable thyroid branches, sometimes with branches to the trachea or neighboring structures.