Inferior thyroid veins

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

The inferior thyroid veins two, frequently three or four, in number, arise in the venous plexus on the thyroid gland, communicating with the middle and superior thyroid veins.

They form a plexus in front of the trachea, behind the Sternothyreoidei.

From this plexus, a left vein descends and joins the left innominate trunk, and a right vein passes obliquely downward and to the right across the innominate artery to open into the right innominate vein, just at its junction with the superior vena cava; sometimes the right and left veins open by a common trunk in the latter situation.

These veins receive esophageal tracheal, and inferior laryngeal veins, and are provided with valves at their terminations in the innominate veins.

Additional images

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  The arch of the aorta, and its branches.
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  The fascia and middle thyroid veins.
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  The thymus of a full-time fetus, exposed in situ.