A 55-year-old man presented with intracerebral hemorrhage and his angiographic evaluation revealed a S-M Grade 4 AVM in his right parietal area [] and was selected for microsurgery. As demonstrated in Figure –, ICG studies are helpful in different stages of the surgery. After opening the dura, the AVM is observed [], and ICG-VA shows the precise anatomy of the vessels []. To distinguish arteries from veins, this image was further reinforced by the color-coded FLOW 800 [] where one can observe the feeding artery in red and the draining vein in blue. This visual color map featured an overview of blood flow dynamics and facilitated identifying the feeding arteries at a single glance. As the operation goes on, changes of blood flow in AVM can be tracked by further color-coded images []. When the resection was completed, a final ICG-VA depicted total AVM removal with no residual nidus [].
A 51-year-old woman who experienced massive intraventricular hemorrhage due to presence of a post-central parasagittal AVM, Spetzler & Martin grade 3, underwent surgery (Figures and ). In this case, we performed right frontoparietal craniotomy and approached the AVM via right interhemispheric route (). However, through the delay map, visualization of the precise structure of the AVM was not possible due to depth of the nidus and angle of the surgical approach (); moreover, due to swelling of the brain, exposure of the AVM was unstable.