title: The Position and Role of Four-Dimensional Computed Tomography Angiography in the Diagnosis and Treatment of Spinal Arteriovenous Fistulas.
abstract: BACKGROUND
  Localization of the arteriovenous fistula (AVF) is a crucial step in the diagnosis and treatment of spinal vascular malformations (VMs). Noninvasive angiographic techniques such as dynamic magnetic resonance angiography and three-dimensional computed tomography angiography (CTA) have been used as standard modalities to localize AVF. With the increasing prevalence of high-specification computed tomography scanners, four-dimensional (4D) CTA is being increasingly used in the evaluation of cerebrovascular disorders. However, application of 4D-CTA in spinal lesions has been limited. The position and role of 4D-CTA, among various modalities, in the evaluation of spinal VMs has not been elucidated.
  
  
  METHODS
  We retrospectively review our clinical experience with 4D-CTA used for spinal AVFs. 4D-CTA images were acquired in 10 cases of spinal VMs consisting of 8 dural/epidural AVFs and 2 perimedullary AVFs. Imaging findings of 4D-CTA and digital subtraction angiography were reviewed to validate the usefulness of 4D-CTA.
  
  
  RESULTS
  In 9 of 10 cases, 4D-CTA accurately localized the AVF. The scan visualized direction of flow in the perimedullary veins in all cases. Regarding perimedullary AVFs, 4D-CTA showed dynamic images of feeding arteries, AVF, and perimedullary drainage. Information provided by 4D-CTA was beneficial as a reference in subsequent DSA.
  
  
  CONCLUSIONS
  In the diagnostic process of spinal VMs, the position of 4D-CTA is the third choice for noninvasive angiography, after dynamic MRA and three-dimensional CTA. However, the role of 4D-CTA might be decisive in difficult-to-find spinal dural AVFs. We believe that this novel imaging technique can be applied in spinal VMs.
authors.affiliation: Department of Neurosurgery, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan. Electronic address: satjp02@gmail.com.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamaguchi
authors.affiliation: Technical Division of Diagnostic Imaging, Itsukaichi Memorial Hospital, Hiroshima, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Takemoto
authors.affiliation: Department of Neurosurgery, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Takeda
authors.affiliation: Department of Neurosurgery, Itsukaichi Memorial Hospital, Hiroshima, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Kajihara
authors.affiliation: Department of Neurosurgery, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Mitsuhara
authors.affiliation: Department of Neurosurgery, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Manish
authors.initials: M
authors.lastname: Kolakshyapati
authors.affiliation: Department of Neurosurgery, Itsukaichi Memorial Hospital, Hiroshima, Japan.
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Mukada
authors.affiliation: Department of Neurosurgery, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kurisu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D001164:Arteriovenous Fistula / Q000000981:diagnostic imaging* / Q000601:surgery; D020785:Central Nervous System Vascular Malformations / Q000000981:diagnostic imaging* / Q000601:surgery; D000072226:Computed Tomography Angiography; D005260:Female; D056973:Four-Dimensional Computed Tomography; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013118:Spinal Cord Diseases / Q000000981:diagnostic imaging* / Q000601:surgery; D025321:Surgery, Computer-Assisted
keywords: 4D-CTA; Difficult-to-find arteriovenous fistula; Spinal arteriovenous fistula; Temporal resolution