title: Volumetric analysis of intracranial arteriovenous malformations contoured for CyberKnife radiosurgery with 3-dimensional rotational angiography vs computed tomography/magnetic resonance imaging.
abstract: BACKGROUND
  Accurate target delineation has significant impact on brain arteriovenous malformation (AVM) obliteration, treatment success, and potential complications of stereotactic radiosurgery.
  
  
  OBJECTIVE
  We compare the nidal contouring of AVMs using fused images of contrasted computed tomography (CT) and magnetic resonance imaging (MRI) with matched images of 3-dimensional (3-D) cerebral angiography for CyberKnife radiosurgery (CKRS) treatment planning.
  
  
  METHODS
  Between May 2009 and April 2012, 3-D cerebral angiography was integrated into CKRS target planning for 30 consecutive patients. The AVM nidal target volumes were delineated using fused CT and MRI scans vs fused CT, MRI, and 3-D cerebral angiography for each patient.
  
  
  RESULTS
  The mean volume of the AVM nidus contoured with the addition of 3-D cerebral angiography to the CT/MRI fusion (9.09 cm(3), 95% confidence interval: 5.39 cm(3)-12.8 cm(3)) was statistically smaller than the mean volume contoured with CT/MRI fused scans alone (14.1 cm(3), 95% confidence interval: 9.16 cm(3)-19.1 cm(3)), with a mean volume difference of δ = 5.01 cm(3) (P = .001). Diffuse AVM nidus was associated with larger mean volume differences compared with a compact nidus (δ = 6.51 vs 2.11 cm(3), P = .02). The mean volume difference was not statistically associated with the patient's sex (male δ = 5.61, female δ = 5.06, P = .84), previous hemorrhage status (yes δ = 5.69, no δ = 5.23, P = .86), or previous embolization status (yes δ = 6.80, no δ = 5.95, P = .11).
  
  
  CONCLUSIONS
  For brain AVMs treated with CKRS, the addition of 3-D cerebral angiography to CT/MRI fusions for diagnostic accuracy results in a statistically significant reduction in contoured nidal volume compared with standard CT/MRI fusion-based contouring.
authors.affiliation: †Departments of Neurological Surgery, Stanford University School of Medicine, Stanford, California; ‡Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California; §Department of Surgery, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: Anand
authors.initials: A
authors.lastname: Veeravagu
authors.forename: Ake
authors.initials: A
authors.lastname: Hansasuta
authors.forename: Bowen
authors.initials: B
authors.lastname: Jiang
authors.forename: Aftab S
authors.initials: AS
authors.lastname: Karim
authors.forename: Iris C
authors.initials: IC
authors.lastname: Gibbs
authors.forename: Steven D
authors.initials: SD
authors.lastname: Chang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001164:Arteriovenous Fistula / Q000473:pathology* / Q000601:surgery; D002533:Cerebral Angiography; D002648:Child; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D002538:Intracranial Arteriovenous Malformations / Q000473:pathology* / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D016634:Radiosurgery; D025321:Surgery, Computer-Assisted; D014057:Tomography, X-Ray Computed; D055815:Young Adult