title: How reliable and accurate is indocyanine green video angiography in the evaluation of aneurysm obliteration?
abstract: BACKGROUND
  Indocyanine green video angiography (ICG-VA) has been recently introduced into neurovascular surgery and gained a role in assessing vessel patency and obliteration of intracranial aneurysms (IA) after clipping. Although its correlation with intra-postoperative angiography was demonstrated in previous studies, difficulties in evaluating aneurysm obliteration have not been reported. We report reliability and accuracy of ICG-VA in 109 clipped aneurysms with attention given to five cases in which ICG-VA evaluation resulted in false indication that aneurysms were secure in terms of complete obliteration.
  
  
  METHODS
  A retrospective chart review was performed of IAs surgically treated by a single surgeon from January 2009. In all cases, aneurysm obliteration was confirmed by a combination of microdoppler ultrasonography (MUSG), ICG-VA, and post-operative angiography.
  
  
  RESULTS
  ICG-VA appropriately assessed vessel patency and aneurysm obliteration in 93.5% of aneurysms clipped. In four cases (3.6%), puncturing the dome of the aneurysm after satisfactory clipping revealed persistent flow within the aneurysm despite ICG-VA showing no flow after clipping. In one case (0.9%), ICG-VA showed persistent flow within the aneurysm and MUSG did not, and puncture of the dome confirmed no flow within the aneurysm. In one case (0.9%), ICG-VA failed to demonstrate residual neck.
  
  
  CONCLUSIONS
  ICG-VA is a simple and safe procedure and an important adjunct to microsurgical clipping of aneurysm. Although ICG-VA assesses vessel patency and obliteration of aneurysms in most cases, applying the principles of microsurgery in aneurysm clipping remains a main tool for obtaining the complete obliteration of aneurysm along with preservation of the normal vasculature.
authors.affiliation: Department of Neurological Surgery, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53792, USA.
authors.forename: Erkin
authors.initials: E
authors.lastname: Özgiray
authors.forename: Erinç
authors.initials: E
authors.lastname: Aktüre
authors.forename: Nirav
authors.initials: N
authors.lastname: Patel
authors.forename: Christopher
authors.initials: C
authors.lastname: Baggott
authors.forename: Melih
authors.initials: M
authors.lastname: Bozkurt
authors.forename: David
authors.initials: D
authors.lastname: Niemann
authors.forename: Mustafa K
authors.initials: MK
authors.lastname: Başkaya
mesh_terms: D000328:Adult; D000368:Aged; D017542:Aneurysm, Ruptured / Q000601:surgery; D000792:Angiography; D015901:Angiography, Digital Subtraction; D002533:Cerebral Angiography / Q000379:methods*; D004396:Coloring Agents; D003399:Craniotomy; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007208:Indocyanine Green; D002532:Intracranial Aneurysm / Q000473:pathology* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D019635:Neurosurgical Procedures; D015203:Reproducibility of Results; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures / Q000379:methods
chemical_list: D004396:Coloring Agents; D007208:Indocyanine Green