THE VEINS OF THE EXTERIOR OF THE HEAD AND FACE 645 



form the angular vein. Occasionally the frontal veins join to form a single trunk, 

 which bifurcates at the root of the nose into the two angular veins. 



The supraorbital vein (v. supraorbiialis) begins on the forehead where it com- 

 municates with the frontal branch of the superficial temporal vein. It runs down- 

 ward superficial to the Frontalis muscle, and joins the frontal vein at the medial 

 angle of the orbit to form the angular vein. Previous to its junction with the frontal 

 vein, it sends through the supraorbital notch into the orbit a branch which com- 

 municates with the ophthalmic vein; as this vessel passes through the notch, it 

 receives the frontal diploic vein through a foramen at the bottom of the notch. 



The angular vein (v. angularis) formed by the junction of the frontal and supra- 

 orbital veins, runs obliquely downward, on the side of the root of the nose, to tlje 

 level of the lower margin of the orbit, where it becomes the anterior facial vein. 

 It receives the veins of the ala nasi, and communicates with the superior ophthalmic 

 vein through the nasofrontal vein, thus establishing an important anastomosis 

 between the anterior facial vein and the cavernous sinus. 



The anterior facial vein (v. facialis anterior; facial vein) commences at the side 

 of the root of the nose, and is a direct continuation of the angular vein. It lies 

 behind the external maxillary (facial) artery and follows a less tortuous course. 

 It runs obliquely downward and backward, beneath the Zygomaticus and zygo- 

 matic head of the Quadratus labii superioris, descends along the anterior border 

 and then on the superficial surface of the Masseter, crosses over the body of the 

 mandible, and passes obliquely backward, beneath the Platysma and cervical 

 fascia, superficial to the submaxillary gland, the Digastricus and Stylohyoideus. 

 It 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 vari- 

 able point belo\v 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 facial vein has no valves, and its 

 walls are not so flaccid as most superficial veins. 



Tributaries. The anterior facial vein receives a branch of considerable size, 

 the deep facial vein, from the pterygoid venous plexus. It is also joined by the 

 superior and inferior palpebral, the superior and inferior labial, the buccinator 

 and the masseteric veins. Below the mandible it receives the submental, palatine, 

 and submaxillary veins, and, generally, the vena comitans of the hypoglossal nerve. 



The superficial temporal vein (v. temporalis superficialis} begins on the side and 

 vertex of the skull in a plexus which communicates \vith the frontal and supra- 

 orbital veins, w^ith the corresponding vein of the opposite side, and with the pos- 

 terior auricular and occipital veins. From this net-work frontal and parietal branches 

 arise, and unite above the zygomatic arch to form the trunk of the vein, which is 

 joined in this situation by the middle temporal vein, from the substance of the Tem- 

 poralis. It then crosses the posterior root of the zygomatic arch, enters the sub- 

 stance of the parotid gland, and unites with the internal maxillary vein to form the 

 posterior facial vein. 



Tributaries. The superficial temporal vein receives in its course some parotid 

 veins, articular veins from the temporomandibular joint, anterior auricular veins 

 from the auricula, and the transverse facial from the side of the face. The middle 

 temporal vein receives the orbital vein, which is formed by some lateral palpebral 

 branches, and passes backward between the layers of the temporal fascia to join 

 the superficial temporal vein. 



The pterygoid plexus (plexus pterygoideus] is of considerable size, and is situated 

 between the Temporalis and Pterygoideus externus, and partly between the two 

 Pterygoidei. It receives tributaries corresponding with the branches of the internal 

 maxillary artery. Thus it receives the sphenopalatine, the middle meningeal, the 

 deep temporal, the pterygoid, masseteric, buccinator, alveolar, and some palatine 



