A 33-year-old man with an unruptured right-occipital AVM underwent surgical treatment (Figures and ). Intraprocedural delay mapping provided a detailed color-coded image after opening of the dura (Figures and ); and the location of the nidus and main feeders was visualized. Based on the findings, we occluded the feeders and achieved complete removal of the AVM with accurate dissection plane between the nidus and normal brain tissue.
Figure – shows a 62-year-old man diagnosed with a cerebellar AVM with feeders from left superior and posterior inferior cerebellar arteries. After exposing the lesion, ICG-VA demonstrates AVM vessels []. illustrates the same view after being rendered by the FLOW 800. Early appearing blood flow is showed in red and late appearing flow in blue. After selecting ROIs for the software, semi-quantitative characteristics of the blood flow in desired vessels were analyzed and demonstrated in curves by the FLOW 800 []. After microsurgical resection of the AVM was complete, ICG-VA showed no remnant of the AVM []. Visual color map showed hemodynamic changes after AVM resection [] in contrast with preresection status []. Furthermore, analytical graphs show changes in flow parameters immediately after AVM resection [Figure and ]. To make it easy to understand, we removed all curves of except for one to demonstrate image analysis performed with ImageJ software []. Time to peak, rise time, and MFI are all showed on the curve. Although CBFI is also calculated, we should notice that this curve is derived from a venous blood flow not brain parenchyma and this index is demonstrated as an example to explain its calculation.