The temporoparietalis is a thin sheet arising from the temporal fascia above and anterior to the ear. It is divided into three parts that spread out like a fan over the temporal fascia. There is a temporal part anteriorly, a parietal part superiorly, and a triangular part between. The temporoparietalis inserts into the lateral border of the galea aponeurotica. The auricularis anterior and superior are recognized as small but inconstant muscle bellies that contribute to this layer.¹

The key to the anatomy of the temporoparietal fascial flap is an understanding of the relationship of the superficial temporal vessels to the layers of the scalp (Fig. 6.1). The specific fascia carried by the superficial temporal vessels is the temporoparietalis fascia with its upper galeal aponeurotic extension. The temporoparietalis fascia must be distinguished from the denser and anatomically deeper temporalis fascia, which invests the temporalis muscle. Confusion arises at the level of zygoma, where both the temporalis and temporoparietalis fasciae attach.

At the level of the ear, the vessels are found deep to the subdermal fat and on the surface of the temporoparietalis fascia. At a level approximately 10 cm above the crus helix, the vessels take a more superficial course, penetrating the subdermal fat and eventually entering the subdermal plexus. While there is some variance in the level at which the axial vessels become contiguous with the subdermal plexus, generally this occurs 12 cm above the crus helix. At this level, a subdermal dissection violates the blood supply and thereby describes the limit of the fascial vascular domain.