Custom Made Device for Intraoperative Fluorescein Videoangiography for Clip Ligation of Cerebral Aneurysms

Background: Intraoperative digital subtraction angiography remains the gold standard to assess parent vessel patency and aneurysm obliteration but is a time-consuming technique that carries procedural risk and may not assess small perforating vessels. The use of indocyanine green and fluorescein videoangiography is a useful tool for confirmation of aneurysm occlusion and patency of all the branches and perforating vessels.

Methods: We have built a 3D printed device with an excitation and a barrier filter to use in surgical microscopes. After the clip ligation of the aneurysm the patients received an intravenous or intra-arterial dose of sodium fluorescein in bolus. We evaluated aneurysm occlusion and patency of the perforators and branches.

Results: Fluorescein is an organic dye widely and safely used in humans. It requires a blue light source and an interposition of a yellow filter to see it properly. It is a highly fluorescent molecule and is excited by light with a wavelength between 465 and 490 nm and has a peak emission between 520 and 530 nm. In all cases fluorescence was clearly visualized in cerebral arteries, and veins, even in deep surgical field and small perforating arteries. These images allowed us to successfully evaluate the aneurysm occlusion and patency of all the branches and perforating vessels.

Conclusion: This is a low-cost option for intraoperative fluorescein videoangiography. It is easy to use, fast and with sufficient image quality for the evaluation of the blood flow even in small vessels and in deep surgical field. It allows to assess the flow in the branches and perforating arteries, and to confirm aneurysm occlusion avoiding complications.