[Effects of surgical microscope-based indocyanine green videoangiography during aneurysm surgery]

To evaluate the effects of surgical microscope-based indocyanine green videoangiography (ICGA) in aneurysm surgery and compare the values of ICGA and postoperative digital subtraction angiography (DSA).

101 patients with intracranial aneurysm underwent clipping of 113 aneurysms. A microscope-integrated light source containing infrared excitation light illuminated the operating field. The dye ICG was injected intravenously, and the intravascular fluorescence was recorded by a video camera attached to the microscope with optical filtering to block ambient and laser light for collection of only ICG-induced fluorescence. All patients underwent DSA 6-13 days post-operatively. The results of patency of parent, branching, and perforating arteries and documentation of aneurysm obliteration shown by ICGA and DSA were compared.

219 times of ICGA was performed in these 101 patients with excellent image quality and resolution, allowing intra-operative real-time assessment of the cerebral circulation. The ICG angiographic results could be divided into arterial, capillary, and venous phases, comparable to those observed with DSA. In all cases, the postoperative angiographic results corresponded to the intraoperative ICG video angiographic findings. In 3 cases, the information provided by intraoperative ICGA significantly changed the surgical procedure.

Simple and repeatable, microscope-based ICGA provides real-time information about vessels and aneurysm sac. This technique may be useful during routine aneurysm surgery as an adjunct to intraoperative microvascular Doppler ultrasonography and DSA.