The anterior facial vein usually unites with the posterior facial vein to form the common facial vein, which crosses the external carotid artery and enters the internal jugular vein at a variable point below the hyoid bone.
From near its termination a communicating branch often runs down the anterior border of the Sternocleidomastoideus to join the lower part of the anterior jugular vein.
The common facial vein is not present in all individuals.
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This article incorporates text from a public domain edition of Gray's Anatomy.