Mastoid Epidermoid Tumor and Associated Dural Arteriovenous Fistula with Venous Sinus Occlusion

• Published in: World neurosurgery 2017-12, Vol.108, p.988.e15-988.e20
• Main Authors: Yoon, Jang W., Hamade, Youssef J., Navarro, Ramon, Brown, Benjamin L., Lundy, Larry, Tawk, Rabih G.
• Format: Article
• Language: English
• Subjects: Central Nervous System Vascular Malformations - complications; Central Nervous System Vascular Malformations - diagnostic imaging; Central Nervous System Vascular Malformations - therapy; Cerebral Angiography; Cranial Sinuses; Diffusion Magnetic Resonance Imaging; Dural arteriovenous fistula; Embolization, Therapeutic; Epidermal Cyst - complications; Epidermal Cyst - diagnostic imaging; Epidermal Cyst - surgery; Epidermoid tumor; Humans; Intracranial Pressure; Intraoperative monitoring; Magnetic Resonance Imaging; Mastoid - diagnostic imaging; Mastoid - surgery; Middle Aged; Monitoring, Intraoperative; Neurosurgical Procedures; Venous hypertension; Venous Pressure
• ISSN: 1878-8750; 1878-8769
• DOI: 10.1016/j.wneu.2017.08.047

Dural arteriovenous fistula (DAVF) is an abnormal vascular connection between arterial and venous channels within dura mater. Although DAVFs have been linked to other types of intracranial tumors, this is the first case reporting the association between DAVF and an epidermoid tumor. A middle-aged patient with chronic headache presented with Borden type II DAVF draining into the right transverse sigmoid junction and was also found to have an epidermoid tumor over the right mastoid. The patient underwent staged embolization of the fistula through both transvenous and transarterial routes. Continuous intraoperative venous pressure monitoring confirmed marked reduction in intracranial venous pressure, and the patient's symptoms completely resolved. However, the fistula still remained. The residual DAVF was then surgically disconnected, and the epidermoid tumor was resected in the same procedure. This case demonstrates a DAVF can be associated with an epidermoid tumor. Tumor can compromise the venous outflow, which can then lead to intracranial venous hypertension and development of the DAVF. Venous pressure monitoring offers an objective method to verify resolution of venous hypertension, which might correlate with resolution of clinical symptoms.