Anatomy of the infratemporal crest: implications for cross-facial nerve grafting in temporal myoplasty.

Temporalis transfers for reanimation in facial palsy have been criticised for the lack of neural input from a functioning facial nerve. Cross-facial nerve grafting to the deep temporal nerves may provide a solution. An anatomical study was performed to further elucidate the deep temporal nerves (DTN) and arteries, examining anatomical variation and infratemporal distribution. Seventeen temporalis muscles were dissected from 13 cadavers as part of a BSc project. The number, branching pattern, length and diameter of DTN were recorded. Arteries supplying the deep surface of temporalis and their relation to DTN were noted. Six specimens were processed using Sihler's staining technique. Arteries were injected with Iodixanol X-ray contrast medium and radiographs taken. All specimens displayed a single DTN originating from the anterior branch of V(3). A mean of 3 branches was observed. The nerve length was 14.22±3.95 mm. The point of entry of DTN into temporalis showed great consistency. Upon exiting the infratemporal fossa, the posterior deep temporal artery was deep and posterior to DTN in 65% of specimens. The branching pattern of DTN can be classified into three types. The deep arterial supply to temporalis was constant in all specimens. This study provides an anatomical basis for the planning and execution of cross-facial nerve grafting to temporalis, and for protection of vital structures. Furthermore, it helps to clarify inconsistencies in the literature regarding nomenclature of the nerve branching pattern of the deep temporal nerves. Copyright Â