The High Perimandibular Approach for Excision of an Intramasseter Tumor: A Clinical Report

A case of an intramasseter vascular malformation excised by the high perimandibular approach (alternatively called high submandibular transmasseteric approach) is presented. A 46-year-old Japanese woman complained of swelling of the right buccal region. Computed tomography (CT) of the right intramasseter region showed a radiolucent area of about 2 cm that included a rounded radiopaque lesion at the masseter muscle. Magnetic resonance imaging (MRI) showed hyperintensity on short T1 inversion recovery (STIR) images and T2-weighted images in the right masseter muscle lesion with the rounded hypointensity signal areas. A vascular malformation of the right masseter muscle was diagnosed, and, considering the size and location of the tumor, surgery was scheduled and performed by the high perimandibular approach. After placing the skin incision below the edge of the angle of the mandible, the skin and subcutaneous tissue were dissected and undermined upward over the platysma muscle. Then, the platysma muscle was incised, followed by exposure of the masseter muscle. After exposing the tumor lesion, tumor dissection with muscle tissue was performed under clear, direct visualization. The final diagnosis was an intramasseter venous malformation. There were no postoperative complications such as facial palsy or trismus. The patient was satisfied with the aesthetic outcome, and recurrence has not been seen 12 months after treatment. Considering the size and location of the tumor, the high perimandibular approach is an effective and useful alternative for intramasseter muscle tumors. (C) 2020 Asian AOMS, ASOMP, JSOP, JSOMS, JSOM, and JAMI. Published by Elsevier Ltd. All rights reserved.