Fluorescence video angiography has recently been introduced in neurosurgery. Such videos are analysed by a new software to allow quantitative characterization of the blood flow during neurovascular operations (clipping an aneurysm, treatment of an angioma). For these purposes the fluorescence dye Indocyanin Green is given intravenously. After activation by a near-infrared light source the fluorescence signal is evaluated by the software. Reference measurements by using a flow phantom were performed to verify the quantitative blood flow results of the software and to validate the software algorithms. The analysis of intraoperative videos provided characteristic biological parameters allowing their implementation in the flow phantom. Under certain conditions the experiments with the help of the flow phantom showed, the results of the software parameter identification algorithmus are within the range of parameter accuracy by the reference method.