Anatomy of the temporalis fascia.

The anatomy of the different layers of the temporalis fascia is reviewed. The superficial and deep layers of the temporalis fascia have been studied by light microscopy to assess any histological difference between the two. We have also assessed the physical characteristics of the different layers by measuring their Young's modulus in the wet and dry states. Anatomically the superficial layer is part of the epicranial aponeurosis and thus covers nearly the entire lateral aspect of the skull. The deep temporal fascial layer covers exactly the temporalis muscle and measures 10 x 12 cm. The fascial layers have a separate arterial and venous supply enabling them to be used as a homograft, a rotation flap or free microvascular flap. Histologically there is no difference between the two layers. A study of the physical characteristics of the two fascial layers using Young's modulus revealed no significant difference in elasticity between the two. The most significant factor affecting the elasticity was the state of hydration of the fascia.