The infrazygomatic segment of the superficial temporal artery: Anatomy and technique for harvesting a better interposition graft

BACKGROUND: The superficial temporal artery (STA) is underutilized as an interposition graft because current techniques expose and harvest STA above the level of the zygoma. This technique yields a diminutive arterial segment in both length and diameter, which limits its use for extracranial-intracranial bypass. OBJECTIVE: To introduce a safe and efficient technique for harvesting of the infrazygomatic segment of the STA. METHODS: Scalp layers, STA, and the facial nerve were studied in 18 specimens. The length of the STA segment harvested below the superior border of the zygomatic arch was measured. Safety of this technique was assessed by measuring the distance between the facial nerve and the STA. RESULTS: The galea and subgaleal fat padwere the only anatomical planes found between the facial nerve and the STA below the zygomatic arch. A dense subcutaneous band of galea contained the STA and allowed proximal dissection of the artery without exposing the facial nerve. The average length of the artery harvested between the zygomatic arch and the parotid gland was 20 mm. CONCLUSION: Subcutaneous dissectionwithin the galea belowthe level of the zygomatic arch and preservation of the dense subcutaneous band surrounding the STA avoids transecting the facial nerve branches while providing increased STA exposure. This anatomical knowledgemay increase the use of STA as an interposition graft in cerebrovascular bypass procedures and reduce the need to harvest grafts through additional incisions at remote sites.