title: Near-infrared indocyanine green video angiography: a new method for intraoperative assessment of vascular flow.
abstract: OBJECTIVE
  We report our initial clinical experience with a new method for intraoperative blood flow assessment. The purposes of the study were to assess the use of indocyanine green (ICG) video angiography in neurovascular cases, to assess the handling and image quality, to compare the findings with postoperative angiographic results, and to evaluate the clinical value of the method in a preliminary feasibility study.
  
  
  METHODS
  Fourteen patients with aneurysms (n = 12) or spinal (n = 1) or intracranial (n = 1) dural fistulae were included. Before and/or after aneurysm or dural fistula occlusion, ICG (25 mg) was injected intravenously. A near-infrared laser excitation light source (lambda = 780 nm) illuminated the operating field. The intravascular fluorescence of ICG (maximal lambda = 835 nm) was recorded by a nonintensified video camera, with optical filtering to block ambient and laser light for collection of only ICG-induced fluorescence.
  
  
  RESULTS
  A total of 21 investigations were performed for 14 patients. For the 17 successful ICG video angiographic investigations, image quality and resolution were excellent, allowing intraoperative real-time assessment of the cerebral circulation. ICG angiographic results could be divided into arterial, capillary, and venous phases, comparable to those observed with digital subtraction angiography. In all cases, the postoperative angiographic results corresponded to the intraoperative ICG video angiographic findings. In three cases, the information provided by intraoperative ICG angiography significantly changed the surgical procedure.
  
  
  CONCLUSIONS
  ICG video angiography is simple and provides real-time information on the patency of arterial and venous vessels of all relevant diameters, including small and perforating arteries (<0.5 mm), and the visible aneurysm sac. It may be a useful adjunct to improve the quality of neurovascular procedures and to document the intraoperative vascular flow.
authors.affiliation: Department of Neurosurgery, Neurocenter, Johann Wolfgang Goethe University Frankfurt am Main, Frankfurt am Main, Germany. A.Raabe@em.uni-frankfurt.de
authors.forename: Andreas
authors.initials: A
authors.lastname: Raabe
authors.forename: Jürgen
authors.initials: J
authors.lastname: Beck
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Gerlach
authors.forename: Michael
authors.initials: M
authors.lastname: Zimmermann
authors.forename: Volker
authors.initials: V
authors.lastname: Seifert
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D001921:Brain / Q000098:blood supply*; D020785:Central Nervous System Vascular Malformations / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D002533:Cerebral Angiography / Q000295:instrumentation*; D002648:Child; D005240:Feasibility Studies; D005260:Female; D005451:Fluorescein Angiography / Q000295:instrumentation*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation; D021621:Imaging, Three-Dimensional / Q000295:instrumentation; D007208:Indocyanine Green; D007259:Infrared Rays; D002532:Intracranial Aneurysm / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008833:Microcirculation / Q000503:physiopathology; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation*; D011183:Postoperative Complications / Q000175:diagnosis / Q000503:physiopathology; D012680:Sensitivity and Specificity; D014741:Video Recording / Q000295:instrumentation*
chemical_list: D007208:Indocyanine Green