All the follow ing veins drain into internal jugular vein except:

Ref: Grays Anatomy 40th edition pg: 400Explanation:Retromandibular veinThe superficial temporal vein joins with the maxillary vein to form retromandibular vein.it divides into anterior and posterior division.Anterior division joins with the facial vein to form common facial vein which drains into internal jugular vein.The posterior division joins with the posterior auricular vein to form external jugular vein.Internal Jugular VeinThe internal jugular vein collects blood from the skull, brain, superficial parts of face and neek.It begins at the cranial base in the posterior compartment of the jugular foramen, where it is continuous with the sigmoid sinus.At its origin it is dilated as the superior bulb, which ties below the posterior part of the tympanic floor.The 'nternal jugular vein descends in the carotid sheath, and unites with the subclavian vein, posterior to the sternal end of the clavicle, to form the brachiocephalic vein .Near its termination the vein dilates into the inferior hulb.TributariesThe inferior petrosal sinus Facial veinLingual veinPharyngeal veinSuperior and middle thyroid veinsOccipital vein (Occasionally)The internal jugular vein may communicate with the external jugular vein.The thoracic duct opens near the union of the left subclavian and internal jugular veins, and the right lymphatic duct opens at the same site on the right.