title: Integration of three-dimensional rotational angiography in radiosurgical treatment planning of cerebral arteriovenous malformations.
abstract: OBJECTIVE
  Accuracy in delineating the target volume is a major issue for successful stereotactic radiosurgery for arteriovenous malformations. The aim of the present study was to describe a method to integrate three-dimensional (3D) rotational angiography (3DRA) into CyberKnife treatment planning and to investigate its potential advantages compared with computed tomography angiography (CTA) and magnetic resonance angiography.
  
  
  METHODS
  A total of 20 patients with a diagnosis of cerebral arteriovenous malformation were included in the present study. All patients underwent multislice computed tomography and 3D-volumetric CTA, 3DRA, and 3D magnetic resonance angiography. The contouring of the target and critical volumes was done separately using CTA and thereafter directly using 3DRA. The composite, conjoint, and disjoint volumes were measured.
  
  
  RESULTS
  The use of CTA or 3DRA resulted in significant differences in the target and critical volumes. The target volume averaged 3.49 ± 3.01 mL measured using CTA and 3.26 ± 2.93 mL measured using 3DRA, for a difference of 8% (p < .05). The conjoint and disjoint volume analysis showed an 88% volume overlap. The qualitative evaluation showed that the excess volume obtained using CTA was mostly tissue surrounding the nidus and venous structures. The mean contoured venous volume was 0.67 mL measured using CTA and 0.88 mL (range, 0.1-2.7) measured using 3DRA (p < .05).
  
  
  CONCLUSIONS
  3DRA is a volumetric angiographic study that can be integrated into computer-based treatment planning. Although whether 3DRA provides superior accuracy has not yet been proved, its high spatial resolution is attractive and offers a superior 3D view. This allows a better 3D understanding of the target volume and distribution of the radiation doses within the volume. Additional technical efforts to improve the temporal resolution and the development of software tools aimed at improving the performance of 3D contouring are warranted.
authors.affiliation: Department of Neurosurgery, University of Messina, Messina, Italy. alfredo.conti@unime.it
authors.forename: Alfredo
authors.initials: A
authors.lastname: Conti
authors.forename: Antonio
authors.initials: A
authors.lastname: Pontoriero
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Faragò
authors.forename: Federica
authors.initials: F
authors.lastname: Midili
authors.forename: Carmelo
authors.initials: C
authors.lastname: Siragusa
authors.forename: Francesca
authors.initials: F
authors.lastname: Granata
authors.forename: Antonio
authors.initials: A
authors.lastname: Pitrone
authors.forename: Costantino
authors.initials: C
authors.lastname: De Renzis
authors.forename: Marcello
authors.initials: M
authors.lastname: Longo
authors.forename: Francesco
authors.initials: F
authors.lastname: Tomasello
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000465:Algorithms; D002533:Cerebral Angiography / Q000379:methods*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D002538:Intracranial Arteriovenous Malformations / Q000000981:diagnostic imaging* / Q000601:surgery*; D007558:Italy; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery / Q000379:methods*; D025321:Surgery, Computer-Assisted / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult