title: Venous sacrifice in neurosurgery: new insights from venous indocyanine green videoangiography.
abstract: OBJECTIVE
  The purpose of this paper is to evaluate whether venous indocyanine green (ICG) videoangiography has any potential for predicting the presence of a safe collateral circulation for veins that are at risk for intentional or unintentional damage during surgery.
  
  
  METHODS
  The authors performed venous ICG videoangiography during 153 consecutive neurosurgical procedures. On those occasions in which a venous sacrifice occurred during surgery, whether that sacrifice was preplanned (intended) or unintended, venous ICG videoangiography was repeated so as to allow us to study the effect of venous sacrifice. A specific test to predict the presence of venous collateral circulation was also applied in 8 of these cases.
  
  
  RESULTS
  Venous ICG videoangiography allowed for an intraoperative real-time flow assessment of the exposed veins with excellent image quality and resolution in all cases. The veins observed in this study were found to be extremely different with respect to flow dynamics and could be divided in 3 groups: 1) arterialized veins; 2) fast-draining veins with uniform filling and clear flow direction; and 3) slow-draining veins with nonuniform filling. Temporary clipping was found to be a simple and reversible way to test for the presence of potential anastomotic circulation.
  
  
  CONCLUSIONS
  Venous ICG videoangiography is able to reveal substantial variability in the venous flow dynamics. "Slow veins," when they are tributaries of bridging veins, might hide a potential for anastomotic circulation that deserve further investigation.
authors.affiliation: Department of Neurosurgery, Fondazione IRCCS Istituto Neurologico Besta, Milan, Italy. pferroli@istituto-besta.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Ferroli
authors.forename: Francesco
authors.initials: F
authors.lastname: Acerbi
authors.forename: Giovanni
authors.initials: G
authors.lastname: Tringali
authors.forename: Erminia
authors.initials: E
authors.lastname: Albanese
authors.forename: Morgan
authors.initials: M
authors.lastname: Broggi
authors.forename: Angelo
authors.initials: A
authors.lastname: Franzini
authors.forename: Giovanni
authors.initials: G
authors.lastname: Broggi
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D020785:Central Nervous System Vascular Malformations / Q000000981:diagnostic imaging* / Q000601:surgery; D002533:Cerebral Angiography / Q000379:methods; D002550:Cerebral Veins / Q000000981:diagnostic imaging* / Q000601:surgery; D004396:Coloring Agents; D005260:Female; D005451:Fluorescein Angiography / Q000379:methods; D006801:Humans; D007208:Indocyanine Green; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D019635:Neurosurgical Procedures / Q000379:methods; D014741:Video Recording
chemical_list: D004396:Coloring Agents; D007208:Indocyanine Green