Supplementary Material for: Case Report A case of ear canal cancer with a high venous arch that benefited from an intraoperative navigation system

Introduction
Cancers of the external auditory canal are rare. Surgery may be the treatment of choice for localized cases. Lateral temporal bone resection is one surgical treatment option. It is rarely performed by skilled surgeons and requires caudal and anterior cutting of the tympanic chamber bone, which is not usually performed in ear surgery. It is imperative to ensure that the internal jugular vein and important nerves are present.
Case presentation
In this report, we describe a case of adenoid cystic carcinoma of the external auditory canal in which lateral temporal bone resection was safely performed using intraoperative navigation. A 33-year-old woman was diagnosed with an adenoid cystic carcinoma of the right external auditory canal by another physician and presented to our department. After close examination, she was diagnosed with T3N0M0 cancer of the external auditory canal and was referred to our department for lateral temporal bone resection. Although the patient had a high venous arch, intraoperative navigation enabled unblocked resection without exposing the tumor or damaging the vital tissues.
Conclusion
Intraoperative navigation is considered a safer procedure for lateral temporal bone resection.