Cardiovascular system · Head and neck
Superior thyroid artery !
The superior thyroid artery, the first branch of the external carotid, feeds the top of the thyroid gland and the voice box.
Opens in the Durgical app, no sign-up needed.
What it is
The first branch of the external carotid, down to the top of the thyroid.
What it does
Feeds the thyroid and larynx; tied in thyroid surgery near the external laryngeal nerve.
Key facts
- Origin
- First branch of the external carotid
- Branches
- Superior laryngeal, infrahyoid, SCM, cricothyroid branches
- Supplies
- Upper thyroid pole, larynx
Relations
- Course
- From the external carotid in the carotid triangle, just below the greater horn of the hyoid bone, it curves forward and down under the infrahyoid muscles to the upper pole of the thyroid lobe, where it splits into anterior and posterior glandular branches
- Medial
- Inferior pharyngeal constrictor, on which the external laryngeal nerve runs toward the cricothyroid
- Superficial
- Superior thyroid vein alongside it, then the infrahyoid muscles, platysma and skin
How to find it
Its pulse is not felt separately. In surgery it is found at the upper pole of the thyroid lobe after the sternothyroid is drawn aside; on Doppler ultrasound it is seen entering the upper pole.
On imaging
Colour Doppler ultrasound shows it as the first front branch of the external carotid, near the bifurcation, running down to the upper pole of the thyroid. In Graves disease the gland shows diffusely increased flow (the thyroid inferno) and fast flow in the thyroid arteries. CT angiography shows it before neck surgery or embolisation. Radiographs do not show it.
Clinical notes
- Its cricothyroid branch is a source of bleeding in a cricothyroidotomy placed too high
- Commonly used as a recipient artery for free flaps in head and neck reconstruction
- In carotid endarterectomy it is usually the first external carotid branch met above the bifurcation; it is looped or clamped so that back-bleeding does not obscure the opened artery
Anatomical variants
- Origin varies: the external carotid (classic), the carotid bifurcation or the common carotid; studies differ on which is most frequent
- A common trunk with the lingual artery (thyrolingual trunk) is occasional
- The superior laryngeal artery may arise separately from the external carotid
Test yourself
Think of the answer, then tap the question to see it.
Which nerve runs close to the superior thyroid artery, and how is it protected in thyroidectomy?
The external branch of the superior laryngeal nerve; its branches are tied right on the gland capsule.
What is the usual origin of the superior thyroid artery?
The first branch of the external carotid artery, just below the greater horn of the hyoid; it may arise from the bifurcation or common carotid.
Which branch of the superior thyroid artery bleeds in a cricothyroidotomy placed too high?
The cricothyroid branch, which crosses the upper part of the cricothyroid membrane.
Educational information, not medical advice. For any symptom, see a health professional.
Its names
- Official Latin (TA2)
- arteria thyreoidea superior TA2 4370
- Official Spanish (DeCS)
- Arteria tiroidea superior
- English (TA2)
- Superior thyroid artery
- Also called
- arteria thyreoidea cranialis
Related
Sources: Terminologia Anatomica (TA2); Anatomy, Head and Neck, Thyroid Arteries.
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.
