Vascular supply and drainage for auricle (cadaveric dissection)
(Figure 2):
We dissected cadavers to confirm the vascular structures related to the
auricle (Fig. 2A). The main arterial supply to this area is the branches
of the external carotid artery: posterior auricular artery and
superficial temporal artery. The external carotid artery (ECA) gives off
the posterior auricular artery just before it divides into the maxillary
and superficial temporal arteries, which are terminal branches of the
ECA in the parotid gland. These arteries play an important role in
vascularizing the auricle. Separating the parotid and the
auricle/external auditory canal exposes the middle auricular artery
(Fig. 2B). The superior auricular artery diverges from the superficial
temporal artery and courses superior to the auricle, forming the
arterial network with the posterior auricular artery (Fig. 2B). Partial
removal of the preauricular parotid gland exposes the course of the
middle and inferior auricular artery and posterior auricular artery
(Fig. 2C). The superior, middle, and inferior auricular arteries branch
from the superficial temporal artery and supply the lateral surface of
the auricle. The posterior auricular artery passes anterior to the
mastoid process and supplies the mastoid branch to the skin on the
mastoid process (Fig. 2D), which passes upward to supply the medial
surface of the auricle with three main branches: superior, middle, and
inferior (Fig. 2E). There are several perforating branches that
penetrate the cartilage to form a complex arterial network between the
lateral and medial surface of the auricle (Fig. 2F). The venous drainage
from the auricle follows these arteries and connects to the superficial
temporal vein anteriorly and the posterior auricular vein posteriorly.
The venous plexus around the condyle of the mandible connects to the
superficial temporal vein. The superficial temporal vein also receives
venous flow from the middle temporal, parotid, and transverse facial
veins and forms the retromandibular vein (Fig. 1C, 2G, and H). The
middle temporal vein courses beneath the superficial layer of the deep
temporal fascia and joins the superficial temporal vein approximately 1
cm below the upper border of the zygomatic root. It connects the
supraorbital vein and the superficial temporal vein. The retromandibular
vein divides into two branches. The anterior branch passes forward and
joins the facial vein to form the common facial vein, which ultimately
drains into the internal jugular vein. The posterior auricular vein
descends behind the auricle and joins the posterior branch of the
retromandibular vein to form the external jugular vein (Fig. 2I).