Application of Indocyanine Green During Arteriovenous Malformation Surgery: Evidence, Techniques, and Practical Pearls

Abstract

Indocyanine green (ICG) is a fluorescent molecule that enables visualization of hemodynamic flow through blood vessels. The first description of its application to the resection of arteriovenous malformations (AVMs) did not occur until 2007. Since then, industry leaders have rapidly integrated this optical technology into the intraoperative microscope, and the use of ICG videoangiography (VA) has since become routine in AVM surgery among some academic centers. A number of case series have been published since the introduction of ICG VA to AVM neurosurgery. These early reports with small sample sizes were largely qualitative, assigning to the technology "usefulness" and "benefit" scores as perceived by the operators. This lack of objectivity prompted the development of FLOW 800 software, a proprietary technology of Carl Zeiss Meditec AG (Oberkochen, Germany) that can quantify relative fluorescence intensity under the microscope to generate color maps and intensity curves for ad hoc and post hoc analyses, respectively. However, subsequent case series have done little to quantify the effect of ICG VA on outcomes. The available literature predominately concludes that ICG VA, although intuitive to deploy and interpret, is limited by its dependence on direct illumination and visualization. The subcortical components of AVMs represent a natural challenge to ICG-based flow analysis, and the scope of ICG VA has therefore been limited to AVMs with a high proportion of superficial angioarchitecture. As a result, digital subtraction angiography has remained the gold standard for confirming AVM obliteration. In this review, we provide an overview of the existing literature on ICG VA in AVM resection surgery. In addition, we describe our own experiences with ICG VA and AVMs and offer the senior author's surgical pearls for optimizing the marriage of fluorescence flow technology and AVM resection surgery.

Endoluminal Biopsy for Molecular Profiling of Human Brain Vascular Malformations

“…A craniotomy was tailored to each patient with neuronavigational software in standard fashion, and microsurgical resection was performed with aide of a Zeiss OPMI Pentero 800 operative microscope (Carl Zeiss AG, Oberkochen, Germany). Direct microscopic visualization, including intraoperative indocyanine green angiography, 15 and confirmation with neuronavigational software (BrainLab, Munich, Germany) identified feeding arteries and the nidus and draining veins of the AVM. To maintain 3D orientation, aneurysm clips and AVM microclips (Aesculap, Inc, Center Valley, PA) of different sizes were placed under direct visualization onto feeding arteries of interest, including the endovascular biopsy site, and to mark the AVM nidus.…”

“…A craniotomy was tailored to each patient with neuronavigational software in standard fashion, and microsurgical resection was performed with aide of a Zeiss OPMI Pentero 800 operative microscope (Carl Zeiss AG, Oberkochen, Germany). Direct microscopic visualization, including intraoperative indocyanine green angiography, 15 and confirmation with neuronavigational software (BrainLab, Munich, Cell suspensions were resuspended in fluorescence-activated cell sorting (FACS) buffer and stained with a modified protocol as we described. 8,9,16 Cells were stained with Alexa Fluor 647conjugated monoclonal anti-human CD31 antibody (BD Biosciences, San Jose, CA) and 49,6-diamidino-2-phenylindole (DAPI, Thermo Fisher Scientific).…”

Pseudo-residual nidus after arteriovenous malformation surgery: illustrative case

“…Many reports have been published on the usefulness of ICG-VA in surgery for cerebrovascular diseases, and it is becoming a routine procedure in AVM surgery. 2 , 3 , 6 The procedure not only contributes to understanding the hemodynamics of the nidus but is also useful in confirming the extent of removal in real-time. 2 Thus, ICG-VA is necessary for performing safe AVM surgery.…”

Application of FLOW 800 in extracranial-to-intracranial bypass surgery for moyamoya disease

“…This is a video demonstrating the application of FLOW 800 in extracranial-to-intracranial bypass surgery for moyamoya disease. [1][2][3][4][5] 0:29 FLOW 800. The FLOW 800 software designed by Zeiss utilizes indocyanine green-based videoangiography performed at a region of interest through a semiquantitative analysis based on time to half-maximum intensity and florescence intensity.…”