The temporoparietal fascia is an extension of the subcutaneous musculoaponeurotic system (SMAS), passing superiorly from the face to the scalp. It continues as the galea aponeurotica, the middle of the five layers in the scalp. The two layers above the galea include the more superficial hair-bearing scalp and the subcutaneous fat layer. Just below the galea is a layer of loose areolar tissue. The pericranium is the fifth and deepest layer, adhering tightly to the cranial bone. The temporalis muscle and its fascia lie deep to the temporoparietal fascia inferior to the temporal line. The investing fascia of the temporalis muscle is a separate layer from the temporoparietal fascia. This temporalis muscle fascia follows the temporalis muscle under the zygomatic arch to insert on the coronoid process of the mandible.

The superficial temporal artery and vein provide the circulation to the temporoparietal fascia. They ascend together anterior to the ear, with the larger vein superficial to the artery. The artery is about 2 mm in diameter, and the vein is slightly larger. At the zygomatic arch, the superficial temporal artery branches to form the middle temporal artery that enters the temporalis muscle and contributes part of its blood supply.17 The next branch, to the frontal area of the fascia originates 5 cm distally, followed by an occipital branch.

The frontal branch of the facial nerve (CN VIII) may enter the field of dissection and must be preserved. It follows a course between a point 0.5 cm inferior to the tragus and a point 1.5 cm superior to the lateral brow.18 The nerve must be avoided because the pedicle narrows inferiorly. The auriculo-temporal nerve lies posterior to the vascular pedicle and provides sensation to the scalp. It is sacrificed in the elevation of the fascial flap.

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