title: Hypoglossal canal dural arteriovenous fistula: incidence and the relationship between symptoms and drainage pattern.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the incidence, radiographic findings, relationship between presenting symptoms for treatment and drainage pattern, and treatment outcomes of hypoglossal canal dural arteriovenous fistula (HC-dAVF).
  
  
  METHODS
  During a 16-year period, 238 patients underwent endovascular treatment for cranial dAVF at a single center. The incidence, radiographic findings, relationship between presenting symptoms for treatment and drainage pattern, and treatment outcomes of HC-dAVF were retrospectively evaluated.
  
  
  RESULTS
  The incidence of HC-dAVF was 4.2% (n = 10). Initial symptoms were tinnitus with headache (n = 6), tinnitus only (n = 1), ocular symptoms (n = 1), otalgia (n = 1), and congestive myelopathy (n = 1). Presenting symptoms requiring treatment included ocular symptoms (n = 4), hypoglossal nerve palsy (n = 4), aggravation of myelopathy (n = 1), and aggravation of tinnitus with headache (n = 1). While the affected HC was widened in 4 of 10 patients, hypersignal intensity on source images was conspicuous in all 7 patients who underwent MR angiography (MRA). All ocular symptoms and congestive myelopathy were associated with predominant drainage to superior ophthalmic or perimedullary veins due to antegrade drainage restriction. All patients who underwent transvenous coil embolization (n = 8) or transarterial N-butyl cyanoacrylate (NBCA) embolization (n = 1) improved without recurrence. One patient who underwent transarterial particle embolization had a recurrence 12 months posttreatment and was retreated with transvenous embolization.
  
  
  CONCLUSIONS
  The incidence of HC-dAVF was 4.2% of all cranial dAVF patients who underwent endovascular treatment. Source images of MRA helped to accurately diagnose HC-dAVF. More aggressive symptoms may develop as a result of a change in the predominant drainage route due to the development of venous stenosis or obstruction over time. Transvenous coil embolization appears to be the first treatment of choice.
authors.affiliation: Department of Radiology, Severance Hospital; and.
authors.forename: Jong Won
authors.initials: JW
authors.lastname: Choi
authors.forename: Byung Moon
authors.initials: BM
authors.lastname: Kim
authors.forename: Dong Joon
authors.initials: DJ
authors.lastname: Kim
authors.forename: Dong Ik
authors.initials: DI
authors.lastname: Kim
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Suh
authors.forename: Na-Young
authors.initials: NY
authors.lastname: Shin
authors.forename: Jin Goo
authors.initials: JG
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D020785:Central Nervous System Vascular Malformations / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000628:therapy; D004621:Embolization, Therapeutic / Q000379:methods*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012886:Skull / Q000000981:diagnostic imaging; D016896:Treatment Outcome