下顎骨皮質骨内に発生したまれな動静脈奇形（arteriovenous malformations）の1例

Arteriovenous malformations in the mandible have been rarely reported, and we have not found any cases in which these malformations were confined to the cortical bone. We report a case of arteriovenous malformations in the cortical bone of the mandible. A 76-year-old woman had experienced slight discomfort in her right chin since January 2019, but disregarded it. She was referred to our hospital in October 2019 to treat a mottled resorption around the lower margin of the mandibular midline observed on X-ray images taken at a nearby dental clinic. At the first visit, a painless bone-like mound was palpable on the lower margin at the right side of the anterior mandible. CT revealed a cortical bone protrusion within a honeycomb-like resorption, and MRI(STIR image)showed a slightly uneven high intensity lesion in the area described above. Based on a clinical diagnosis of suspected mandibular tumor, a bone tumor resection was performed using a submental approach under general anesthesia. The histopathological diagnosis was intracortical arteriovenous malformations in the mandible. The patient is doing well without recurrence more than three years after the operation.