Prospective evaluation of surgical microscope-integrated intraoperative near-infrared indocyanine green videoangiography during aneurysm surgery.
OBJECTIVE
The authors prospectively compared a new technique of surgical microscope-based indocyanine green (ICG) videoangiography with intraoperative or postoperative digital subtraction (DS) angiography.


METHODS
The technique was performed during 187 surgical procedures in which 124 aneurysms in 114 patients were clipped. Using a newly developed setup, the ICG technique has been integrated into an operating microscope (Carl Zeiss Co., Oberkochen, Germany). A microscope-integrated light source containing infrared excitation light illuminates the operating field. The dye is injected intravenously into the patient, and intravascular fluorescence from within the blood vessels is imaged using a video camera attached to the microscope. The patency of parent, branching, and perforating arteries and documentation of clip occlusion of the aneurysm as shown by ICG videoangiography were compared with intraoperative or postoperative findings on DS angiography. The results of ICG videoangiography corresponded with intra- or postoperative DS angiography in 90% of cases. The ICG technique missed mild but hemodynamically irrelevant stenosis that was evident on DS angiography in 7.3% of cases. The ICG technique missed angiographically relevant findings in three cases (one hemodynamically relevant stenosis and two residual aneurysm necks [2.7% of cases]). In two cases the missed findings were clinically and surgically inconsequential; in the third case, a 4-mm residual neck may require a second procedure. Indocyanine green videoangiography provided significant information for the surgeon in 9% of cases, most of which led to clip correction.


CONCLUSIONS
Microscope-based ICG videoangiography is simple and provides real-time information about the patency of vessels of all sizes and about the aneurysm sac. This technique may be useful during routine aneurysm surgery as an independent form of angiography or as an adjunct to intra- or postoperative DS angiography.
Raabe
Andreas
A
Department of Neurosurgery, Neurocenter, Johann Wolfgang Goethe University, Frankfurt am Main, Germany.
Nakaji
Peter
P
Beck
Jürgen
J
Kim
Louis J
LJ
Hsu
Frank P K
FP
Kamerman
Jonathan D
JD
Seifert
Volker
V
Spetzler
Robert F
RF
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D001158:Arteries / Q000503:physiopathology; D002533:Cerebral Angiography / Q000592:standards; D004396:Coloring Agents; D005260:Female; D006801:Humans; D007208:Indocyanine Green; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures; D011184:Postoperative Period; D011446:Prospective Studies; D019265:Spectroscopy, Near-Infrared; D025321:Surgery, Computer-Assisted; D013690:Television; D014654:Vascular Patency
D004396:Coloring Agents; D007208:Indocyanine Green