The Subzygomatic Triangle: Rapid, Minimally Invasive Identification of the Masseteric Nerve for Facial Reanimation

Johns Hopkins Medicine, Baltimore, Maryland, United States
Plastic and Reconstructive Surgery (Impact Factor: 3.33). 03/2013; 132(1). DOI: 10.1097/PRS.0b013e318290f6dc
Source: PubMed

ABSTRACT BACKGROUND:: The masseteric nerve is a valuable donor nerve in the management of facial paralysis, however its location is less familiar to surgeons because this motor nerve is not commonly exposed in other head and neck procedures. Current techniques for masseteric nerve identification rely on physical measurements from surface or bony landmarks that may be unpredictable across patient age, ethnicity and size. We sought to identify a rapid and minimally invasive technique based on surgical anatomy independent of intra-operative physical measurements. METHODS:: A two phase fresh frozen cadaver study was performed followed by a clinical application that included 11 consecutive patients undergoing facial reanimation procedures between May 2012 and October 2012. RESULTS:: Ten cadavers were dissected and 11 clinical applications are reported. In all dissections the masseteric nerve was identified through the newly described "Subzygomatic Triangle". This triangle is formed by the zygomatic arch superiorly, the temporomandibular joint posteriorly, and the frontal branch of the facial nerve inferiorly and anteriorly. This finding was consistent across patient ages (8-49 years) and ethnicities. Through using the short scar, minimal dissection approach described in the study, average time to nerve identification was 10.2 minutes during the clinical application. CONCLUSION:: The subzygomatic triangle is a consistent anatomic landmark for rapid, reliable and minimally invasive identification of the masseteric nerve. The use of the subzygomatic triangle obviates the need for extensive dissection and surgeon reliance upon soft tissue measurements that may vary between patients of different size, gender or ethnicity. LEVEL OF EVIDENCE:: IV.

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