The impact of microscope-integrated intraoperative near-infrared indocyanine green videoangiography on surgery of arteriovenous malformations and dural arteriovenous fistulae

Abstract

Background: Microscope-based intraoperative near-infrared indocyanine green (ICG) videoangiography is useful as an adjunct to intra- or postoperative digital subtraction angiography (DSA) in aneurysm surgery.

Objective: To evaluate intraoperative ICG videoangiography for surgery of arteriovenous malformations (AVMs) and dural arteriovenous fistulas (dAVFs).

Methods: Seventeen patients undergoing surgical resection of intracranial AVM or AVF were enrolled into this prospective evaluation. ICG videoangiography sequences were analyzed with regard to transit times to differentiate between arterial, early venous, capillary, and venous phase as well as early passage (fistula) and delayed appearance (ischemia). ICG videoangiography was compared with pre- and postoperative angiography.

Results: Forty-six ICG videoangiographies were performed in 17 operative procedures. In 41 ICG investigations image quality and spatial resolution were excellent to analyze arterial, early venous, capillary, and venous phase. In 2 cases ICG videoangiography provided additional information to change the surgical strategy. With the exception of one case only, the postoperative angiogram corresponded to the last ICG examination performed after the resection. No side effects related to ICG injection were observed. In one patient with a deep thalamic AVM the final ICG investigation was inconclusive owing to insufficient illumination of the deep surgical field.

Conclusion: Microscope-integrated repetitive ICG videoangiography during AVM and dAVF surgery is fast, easy to perform, and safe. This simple and safe real-time method is a useful additional tool that can potentially lower the surgical risk in complex AVMs and help avoid missed residuals.