title: Skull Base Osseous Arteriovenous Fistula-A Rare Clinical Entity: Case Report and Literature Review.
abstract: OBJECTIVE
  To describe a rare clinical entity of intraosseous skull base arteriovenous fistula managed with transvenous fistula embolization.
  
  
  METHODS
  A 57-year-old woman presented with complaints of headache and episodic tinnitus with progressive left-sided visual deterioration. Cross-sectional imaging of the head revealed multiple vascular channels in the sphenoid bone and in bilateral masticator spaces. Catheter angiography showed the presence of a large osseous arteriovenous fistula epicentered in the body of sphenoid and left pterygoid plates with arterial feeders from bilateral external carotid arteries and venous drainage into bilateral cavernous sinuses and the pterygoid venous plexus. She was managed by transvenous coil and liquid embolic agent (Squid 18) embolization of the venous sac with significant reduction of shunt. In the postprocedure period, the patient developed paradoxical worsening of symptoms due to central retinal vein occlusion.
  
  
  CONCLUSIONS
  Skull base osseous fistulae are uncommon clinical entities and fistulae centered within the sphenoid bone are very rare. The aim of this report was to highlight management issues associated with such a case and review the available literature on the subject.
authors.affiliation: Imaging Sciences & Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Kerala, India. Electronic address: romianeesh@gmail.com.
authors.forename: Aneesh
authors.initials: A
authors.lastname: Mohimen
authors.affiliation: Imaging Sciences & Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Kerala, India.
authors.forename: Santhosh
authors.initials: S
authors.lastname: Kumar Kannath
authors.affiliation: Imaging Sciences & Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Kerala, India.
authors.forename: E R
authors.initials: ER
authors.lastname: Jayadevan
mesh_terms: D001164:Arteriovenous Fistula / Q000000981:diagnostic imaging* / Q000601:surgery*; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000000981:diagnostic imaging* / Q000601:surgery*; D008875:Middle Aged; D019291:Skull Base / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000601:surgery*
keywords: Central retinal vein occlusion; Osseous arteriovenous fistula; Skull base arteriovenous fistula; Transvenous embolization