title: Interest of convex spherical anamorphosis in better understanding of brain AVMs' angioarchitecture.
abstract: BACKGROUND
  Convex spherical anamorphosis is a barrel distortion that consists of the application of a plane surface on a convex hemisphere. Applied in vascular imaging of brain arteriovenous malformations (bAVMs), this deformation may help to 'spread' the nidus and surrounding vessels (arteries/veins) and thus to differentiate the different components of bAVMs more accurately.
  
  
  METHODS
  The imaging data from 15 patients (8 male, 7 female; 14 supratentorial bAVMs, 1 infratentorial) were used to test the algorithm. The algorithm was applied to three-dimensional rotational angiography (3D-RA) volume rendering reconstructions in anteroposterior, lateral and oblique views and compared with regular 3D-RA and DSA. Arterial feeder and draining vein count and quality visualization of the main draining vein and intranidal aneurysms were compared between the three imaging techniques.
  
  
  RESULTS
  Anamorphosis was able to depict more arterial feeders than 3D-RA alone (p=0.027). There was no statistically significant difference between 6 f/s DSA and anamorphosis for arterial feeder count. No difference was observed in draining vein count between the three imaging modalities. Visualization of the precise origin of the main draining vein was considered to be good in 67% of the cases with anamorphosis versus 47% and 33% for 6 f/s DSA and 3D-RA alone, respectively. Intranidal aneurysms were accurately depicted by anamorphosis (2 cases), whereas 6 f/s DSA and 3D-RA showed doubtful images in one and two additional cases, respectively, which were finally confirmed as focal venous ectasias on supraselective injection.
  
  
  CONCLUSIONS
  Anamorphosis can help to visualize more precisely the main draining vein origin of the bAVM and depict more accurately intranidal aneurysms.
authors.affiliation: Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital, Paris, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Clarençon
authors.affiliation: Weezin, Saint Cloud, France.
authors.forename: Franck
authors.initials: F
authors.lastname: Maizeroi-Eugène
authors.affiliation: Alioscopy, Paris, France.
authors.forename: Flavien
authors.initials: F
authors.lastname: Maingreaud
authors.affiliation: Department of Neurosurgery, Lariboisière University Hospital, Paris, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Bresson
authors.affiliation: Department of Neurosurgery, Saint-Joseph University Hospital, Beyrouth, Lebanon Department of Neuroradiology, Limoges University Hospital, Limoges, France.
authors.forename: David
authors.initials: D
authors.lastname: Ayoub
authors.affiliation: Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital, Paris, France.
authors.forename: Nader-Antoine
authors.initials: NA
authors.lastname: Sourour
authors.affiliation: Department of Neuroradiology, Montpellier University Hospital, Montpellier, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Menjot de Champfleur
authors.affiliation: Department of Interventional Neuroradiology, Pitié-Salpêtrière Hospital, Paris, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Chiras
authors.affiliation: Department of Histology, Cytology, Cellular Biology and Cytogenetics, Limoges University Hospital, Limoges, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Yardin
authors.affiliation: Department of Neuroradiology, Limoges University Hospital, Limoges, France.
authors.forename: Charbel
authors.initials: C
authors.lastname: Mounayer
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D015901:Angiography, Digital Subtraction; D016477:Artifacts; D002533:Cerebral Angiography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D002538:Intracranial Arteriovenous Malformations / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
keywords: Arteriovenous Malformation; Technology; Vascular Malformation