Venous Drainage

Ashley Davidoff MD

Introduction

Blood drains from the the thyroid via the superior, middle and inferior thyroid veins.

The superior thyroid vein runs with the superior thyroid artery. Each superior thyroid vein drains to ipsilateral internal jugular vein.

The middle veins also drain into the jugular veins bilaterally.

The inferior thyroid vein on the left drains into the brachiocephalic vein while the right may drain into a right sided innominate vein (if present) or into the left sided brachiocephalic vein. Sometimes a common vein called the thyroid ima vein drains the left and right inferior veins via a common channel

Venous Drainage of the Thyroid

This diagram illustrates the venous drainage of the thyroid which is drained by the superior thyroid vein and middle thyroid vein which empty into the jugular vein,and the inferior thyroid vein which usually enters into the brachiocephalic vein.

Venous Anatomy of the Thyroid by Venography

The venogram with injection into the right superior thyroid vein demonstrates the collateral venous connections between all the veins of the thyroid including the superior middle and inferior vessels bilaterally. The injection into the left superior thyroid vein causes expansion of that vein accounting for the asymmetry in size of the two veins Additionally there is a large accessory vein (overlaid in lighter blue) entering the brachiocephalic veins with the much smaller inferior thyroid veins. This may be a thyroid ima vein.

Courtesy Barry Sacks MD 97217cL01.9