Risk of Maxillary Artery Injury During an Intraoral Vertical Ramus Osteotomy in Japanese Patients is High—Is It Enough Just to Avoid Damaging the Inferior Alveolar Nerve?

PurposeSince managing a case in which the maxillary artery was injured during intraoral vertical ramus osteotomy (IVRO) with intraoperative transcatheter arterial embolization, we have conducted preoperative vascular computed tomography (CT) evaluations of the maxillary artery course in patients scheduled to undergo mandibular bone osteotomy. The aim of the present study was to describe the anatomy of the maxillary artery in the infratemporal artery in Japanese patients.Materials and MethodsThe study design was a prospective case series. The study sample included all patients who had undergone IVRO from October 2009 to December 2012. We evaluated the positional relationship between the maxillary artery and the mandible using CT vascular imaging before surgery. The primary outcome variable was the requirement for subperiosteal dissection on the medial surface of the mandible from the perspective of the intersection of the route of the maxillary artery with the IVRO osteotomy line.ResultsA total of 156 sides from 78 patients who had undergone mandibular bone osteotomy were included in the present study. The maxillary artery course was positioned directly below the mandibular notch in approximately one half of the cases, necessitating subperiosteal dissection on the medial surface of the mandible.ConclusionsIVRO is a common surgical procedure that can be safely and easily conducted in conjunction with endoscopy. However, improved maxillary artery damage prevention methods are recommended, such as subperiosteal dissection on the medial surface of the mandible and filling the medial surface of the mandibular ramus with gauze.