title: Postoperative hyperperfusion in dural arteriovenous fistula associated with venous ischemia: case report.
abstract: BACKGROUND
  It is well known that carotid endarterectomy and extracranial-intracranial arterial bypass sometimes cause postoperative hyperperfusion, and vasoparalysis attributable to long-standing ischemia has been suggested as the cause. It is also well known that dural arteriovenous fistula (AVF) sometimes causes cerebral ischemia attributable to venous hypertension. However, there are few reports regarding the postoperative changes of regional cerebral blood flow (rCBF).
  
  
  METHODS
  We report a case of dural AVF of the left transverse/sigmoid sinuses, occurring in a 64-year-old man. Intraoperative transvenous embolization combined with transarterial embolization was performed, and the rCBF was measured pre- and postoperatively using 99mTc-hexamethyl-propylene amine oxime and single-photon emission computed tomography (SPECT).
  
  
  RESULTS
  Preoperative SPECT disclosed a marked rCBF reduction in the left temporal, parietal, and occipital lobes. Complete obliteration of the AVF was attained after the intraoperative transvenous embolization, without any neurological deterioration. However, postoperative SPECT demonstrated temporary hyperperfusion in these regions.
  
  
  CONCLUSIONS
  Sudden resolution of venous ischemia can lead to postoperative hyperperfusion, and pre- and post-treatment rCBF studies are important to prevent complications related to hyperperfusion.
authors.affiliation: Department of Neurosurgery, Hokkaido University School of Medicine, Sapporo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kuroda
authors.forename: S
authors.initials: S
authors.lastname: Ushikoshi
authors.forename: K
authors.initials: K
authors.lastname: Houkin
authors.forename: H
authors.initials: H
authors.lastname: Saito
authors.forename: Y
authors.initials: Y
authors.lastname: Kikuchi
authors.forename: H
authors.initials: H
authors.lastname: Abe
mesh_terms: D001164:Arteriovenous Fistula / Q000601:surgery*; D002545:Brain Ischemia / Q000209:etiology* / Q000503:physiopathology; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation; D004388:Dura Mater / Q000098:blood supply*; D004621:Embolization, Therapeutic / Q000009:adverse effects*; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015899:Tomography, Emission-Computed, Single-Photon; D014656:Vascular Surgical Procedures / Q000009:adverse effects*