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 [].
Case 3: A 62-year-old woman presented with progressive headache and vertigo and was diagnosed as having 2 aneurysms arising from right A2-anterior communicating artery junction, one projecting anteroinferiorly and the other projecting medially []. After clipping of the first aneurysm, micro-Doppler examination detected no flow in the aneurysm. The arterial phase in the ICG-VA also showed lack of flow into the aneurysm and normal flow in the nearby perforating artery. However, the venous phase showed a glimmer of fluorescence visible in the aneurysm sac [], suggestive of residual filling of the aneurysm. The corresponding color map showed a portion of the aneurysm with blue color and a delayed ascending curve (purple color) was detected in the intensity [Figure and ], thus confirming a residual aneurysm. The clip was then readjusted and ICG-VA was repeated. This time it showed complete absence of flow within the aneurysm. A postoperative 3D-CTA demonstrated complete obliteration of the aneurysm.