title: The "ICG Entrapment Sign" in Cerebral Aneurysm Surgery Assisted by Indocyanine Green Videoangiography.
abstract: BACKGROUND
  Indocyanine green videoangiography (ICG-VA) after clipping can be misleading in evaluating aneurysm exclusion when the dye is injected before clipping. This is due to indocyanine green (ICG) entrapment by the clip blades in the aneurysm dome.
  
  
  METHODS
  We examined the intraoperative findings of 7 patients presenting ICG entrapment. In all cases, the clipped aneurysms were opened intraoperatively at the end of the procedure to confirm aneurysm exclusion.
  
  
  RESULTS
  In 4 cases ICG entrapment was caused by dye injection before clipping for the surgical strategy and in 3 cases because the clip was repositioned based on ICG-VA findings. In all cases, the final sac opening confirmed that the dye entrapment indicated complete aneurysm exclusion. In our experience ICG entrapment avoided a second ICG injection in 2 cases and yielded a better understanding of the videoangiographic findings in 5 patients.
  
  
  CONCLUSIONS
  The "ICG entrapment sign" can be used intraoperatively as an indirect sign of excluded aneurysm and can be helpful in the decision-making process for aneurysm treatment when ICG-VA is performed before clipping.
authors.affiliation: Department of Neurosurgery, Padua University Hospital, Padua, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Della Puppa
authors.affiliation: Department of Neurosurgery, Padua University Hospital, Padua, Italy. Electronic address: orielarustemi@libero.it.
authors.forename: Oriela
authors.initials: O
authors.lastname: Rustemi
authors.affiliation: Department of Neurosurgery, Padua University Hospital, Padua, Italy.
authors.forename: Renato
authors.initials: R
authors.lastname: Scienza
mesh_terms: D000328:Adult; D002533:Cerebral Angiography / Q000379:methods*; D005260:Female; D006801:Humans; D007208:Indocyanine Green / Q000008:administration & dosage*; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D019635:Neurosurgical Procedures / Q000379:methods*; D012189:Retrospective Studies; D013525:Surgical Instruments; D014656:Vascular Surgical Procedures / Q000379:methods; D020535:Video-Assisted Surgery / Q000379:methods*
chemical_list: D007208:Indocyanine Green
keywords: Aneurysm clipping; Clip reposition; Complex aneurysms; ICG entrapment; ICG stasis; ICG-VA indirect sign; Intracranial aneurysms