The authors present the case of an 18-year-old male with a deep-seated left fusiform dissecting M3 aneurysm for which endovascular treatment was not applicable. At the open surgery, they used the less commonly reported FLOW 800 fluorescent indocyanine green (ICG) videoangiography, before and after parental aneurysmal artery temporary clipping, to locate the distal outflow branch of the aneurysm and use it as the recipient artery for a superficial temporal artery–M4 bypass, excluding the aneurysm by clipping the parental artery. Repeated ICG FLOW 800 angiography confirmed bypass patency and adequate blood flow. The aneurysm’s exclusion from circulation was confirmed by digital subtraction angiography postoperatively.
The video can be found here: https://stream.cadmore.media/r10.3171/2021.10.FOCVID21183