title: Surgical treatment of poorly visualised and complex cerebrovascular lesions using pre-operative angiographic data as angiographic DynaCT datasets for frameless stereotactic navigation.
abstract: BACKGROUND
  Digital subtraction angiography (DSA) is the "gold standard" for the imaging of cerebrovascular lesions, particularly cerebral aneurysms and arteriovenous malformations (AVMs). Current stereotactic navigation is based on computed tomography (CT) and magnetic resonance (MR) images, which-even despite the use of CT angiographic (CTA) or MR angiographic (MRA) sequences-may not reveal small lesions, and may not demonstrate all the different facets of complex lesions.
  
  
  OBJECTIVE
  To develop frameless stereotactic protocols based on pre-operative cerebral angiograms for enhancing precision in intra-operative navigation and improve patient outcomes.
  
  
  METHODS
  Pre-operative angiograms were obtained for ten patients requiring surgery for complex and/or poorly visualised cerebrovascular lesions. The angiographic data were captured as an angiographic DynaCT dataset and fused to pre-operative CT or MR imaging stereotactic sequences for pre-operative planning and intra-operative navigation. The utility of the angiographic DynaCT datasets for surgical navigation and treatment were assessed by the treating neurosurgeon.
  
  
  RESULTS
  This technique enabled precise navigation and better treatment of cerebrovascular lesions that were either inadequately imaged or invisible to conventional pre-operative CT and/or MR imaging techniques. We found that its use in the surgical excision of a micro-AVM to be far superior to CTA and MRA datasets. Its use in seven cases was found to be superior to CTA and MRA datasets, and as useful as CTA or MRA datasets in two cases.
  
  
  CONCLUSIONS
  Pre-operative formal cerebral angiography as an angiographic DynaCT dataset can be used safely and effectively for intra-operative navigation and treatment of cerebrovascular lesions, in particular, micro-cerebral AVMs.
authors.affiliation: Department of Neurosurgery, The Alfred Hospital, Melbourne, Australia. Jin_Wee@hotmail.com
authors.forename: Jin Wee
authors.initials: JW
authors.lastname: Tee
authors.forename: Michael
authors.initials: M
authors.lastname: Dally
authors.forename: Anoop
authors.initials: A
authors.lastname: Madan
authors.forename: Peter
authors.initials: P
authors.lastname: Hwang
mesh_terms: D000328:Adult; D000368:Aged; D017542:Aneurysm, Ruptured / Q000175:diagnosis* / Q000601:surgery*; D020785:Central Nervous System Vascular Malformations / Q000175:diagnosis* / Q000601:surgery*; D002533:Cerebral Angiography / Q000295:instrumentation*; D002543:Cerebral Hemorrhage / Q000175:diagnosis / Q000601:surgery; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000601:surgery*; D018810:Magnetic Resonance Angiography / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D038361:Neuronavigation / Q000295:instrumentation*; D011300:Preoperative Care; D012680:Sensitivity and Specificity; D012984:Software