gms | German Medical Science

Objective: In extracranial-intracranial bypass surgery it is important to monitor hemodynamic characteristics of the anastomosis as a surrogate for bypass patency, cerebral perfusion and outcome.

We investigated the value of the FLOW 800 software derived from a novel robotic visualization system after indocyanine green (ICG)-angiography as an intraoperative tool for real-time color-coded visualization and quantitative hemodynamic assessment of bypass patency.

Methods: A cohort of 7 patients with either stenoocclusive vessel disease (n=6) or moyamoya vasculopathy (n=1) who underwent extracranial-intracranial bypass surgery was studied. ICG-angiography was performed using a novel intraoperative robotic visualization system and was obtained prior to and after completion of the anastomosis. Flow velocities and transit times derived from FLOW 800-specific hemodynamic parameters were visualized and analyzed in real-time. Intraoperative results were correlated to postoperative catheter angiography and/or computed tomographic (CT) – angiography.

Results: ICG-angiographies and FLOW 800 analyses were performed in 7 operative procedures. In all cases an excellent color-coded visualization as well as quantitative hemodynamic parameters of anastomosis and brain perfusion was noted. Quantitative flow measurements derived from FLOW 800-specific hemodynamic parameters indicated well-functioning bypasses. In all cases, final intraoperative analyses correlated well with the postoperative catheter angiography and/or CT-angiography.

Conclusion: Our data highlights that in contrast to previously used microscopes and the mere visual analysis of ICG-angiography, the novel robotic visualization system allows obtaining quantitative FLOW 800-specific hemodynamic parameters easily and rapidly in real-time. Thus, improved intraoperative visualization and hemodynamic assessment of bypass patency and consecutive cerebral perfusion is facilitated.