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.
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.