title: Flash fluorescence with indocyanine green videoangiography to identify the recipient artery for bypass with distal middle cerebral artery aneurysms:  operative technique.
abstract: BACKGROUND
  Distal middle cerebral artery (MCA) aneurysms frequently have nonsaccular morphology that necessitates trapping and bypass. Bypasses can be difficult because efferent arteries lie deep in the opercular cleft and may not be easily identifiable.
  
  
  OBJECTIVE
  We introduce the "flash fluorescence" technique, which uses videoangiography with indocyanine green (ICG) dye to identify an appropriate recipient artery on the cortical surface for the bypass, enabling a more superficial and easier anastomosis.
  
  
  METHODS
  Flash fluorescence requires 3 steps: (1) temporary clip occlusion of the involved afferent artery; (2) videoangiography demonstrating fluorescence in uninvolved arteries on the cortical surface; and (3) removal of the temporary clip with flash fluorescence in the involved efferent arteries on the cortical surface, thereby identifying a recipient. Alternatively, temporary clips can occlude uninvolved arteries, and videoangiography will demonstrate initial fluorescence in efferent arteries during temporary occlusion and flash fluorescence in uninvolved arteries during reperfusion.
  
  
  RESULTS
  From a consecutive series of 604 MCA aneurysms treated microsurgically, 22 (3.6%) were distal aneurysms and 11 required a bypass. The flash fluorescence technique was used in 3 patients to select the recipient artery for 2 superficial temporal artery-to-MCA bypasses and 1 MCA-MCA bypass. The correct recipient was selected in all cases.
  
  
  CONCLUSIONS
  The flash fluorescence technique provides quick, reliable localization of an appropriate recipient artery for bypass when revascularization is needed for a distal MCA aneurysm. This technique eliminates the need for extensive dissection of the efferent artery and enables a superficial recipient site that makes the anastomosis safer, faster, and less demanding.
authors.affiliation: Department of Neurological Surgery, University of California, San Francisco, California 94143-0112, USA.
authors.forename: Ana
authors.initials: A
authors.lastname: Rodríguez-Hernández
authors.forename: Michael T
authors.initials: MT
authors.lastname: Lawton
mesh_terms: D000293:Adolescent; D000328:Adult; D002548:Cerebral Revascularization / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005451:Fluorescein Angiography / Q000379:methods*; D006801:Humans; D007208:Indocyanine Green; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012189:Retrospective Studies; D020535:Video-Assisted Surgery / Q000379:methods*; D055815:Young Adult
chemical_list: D007208:Indocyanine Green