Anatomic basis of the middle temporal artery periosteal rotational flap in otologic surgery.

OBJECTIVES/HYPOTHESIS To describe the elements critical to successful middle temporal artery periosteal rotational flap harvest and utilization based on the anatomic features of the middle temporal artery. STUDY DESIGN Description of anatomy based on cadaver dissection. METHODS Seventy temporal fossa dissections were performed on 35 adult human cadavers. RESULTS Sixty-nine of 70 dissections had an identifiable middle temporal artery muscular branch pedicle in the periosteum deep to the temporalis muscle. Pedicle length was at least 7 cm in 32 of 38 (84%) male cadavers and in 20 of 31 (65%) female cadavers (P = 0.054), whereas the average length required to reach the digastric ridge from the pedicle base to the digastric ridge in a mastoidectomy cavity was 5.2 cm. The pedicle sharply transitions from a posterior to a posterior-superior course 0.93 cm superior (range: 0.5-1.9 cm) and 0.04 cm posterior (range: 1.4 cm posterior-0.7 cm anterior) to the spine of Henle. Branching occurred in 26 of 69 pedicles (38%), and 20 of 31 (65%) branches were oriented posteriorly. If temporalis muscle fibers are not incorporated into the flap, the thickness is roughly three times that of a standard temporalis fascia graft. CONCLUSION The muscular branch of the middle temporal artery is reliably identified in the periosteum deep to the posterior aspect of the temporalis muscle, and this vessel is sufficiently robust to provide axial blood supply to a rotational periosteal flap that has sufficient thickness and length to allow a variety of applications in otologic surgery. LEVEL OF EVIDENCE NA. Laryngoscope, 126:1426-1432, 2016.