Facial Palsy Following Onyx Embolization of a Glomus Tympanicum Tumor

The embolization of a glomus tumor (GT) is a known preoperative procedure aimed at decreasing the blood supply to the tumor and reducing operative time and blood loss. Liquid embolic material is the preferable embolic agent. However, the incidence of cranial neuropathy due to denaturation with Onyx is not well established. This report seeks to illustrate the outcomes of a combined preoperative Onyx embolization of a glomus tympanicum tumor and highlight the related complications of facial palsy. A 49-year-old woman developed left-sided facial palsy following the preoperative embolization of a left-sided GT with selective transarterial embolization using ethylene vinyl alcohol (EVOH; Onyx 18), which was complicated with left-sided facial weakness 1 h post embolization. An additional uneventful surgical resection of the GT was performed successfully 72 h later. Embolization material poses a risk of cranial neuropathy. Further studies are recommended to support the knowledge of well-established embolization agents that will provide maximal occlusion while minimizing the risk of complications.