Fig 1. Microscope-based indocyanine green video angiography supporting the microsurgical occlusion of a ruptured middle cerebral artery aneurysm, which has been tested but is not used as a routine intraoperative device so far.

(A): Intraoperative illustration of the middle cerebral artery aneurysm (arrows). (B): Video angiography showing the perfusion of the untreated aneurysm (arrows). (C): After clipping no perfusion of the aneurysm is detectable any more (arrows).