INTRODUCTION:We evaluated the feasibility, usefulness, and limitations of near-infrared indocyanine green (ICG) videoangiography during procedures involving the extracranial vertebral artery (VA).
METHODS: Nine patients (2 women, 7 men; mean age, 55 years) were evaluated at 2 neurosurgical centers. Near-infrared ICG videoangiography was applied during transposition and rerouting of the first segment of VA (V1; n = 6) and during resection of neurinomas near the second (V2; n = 1) and third (V3; n = 2) segments of VA.
RESULTS: Early after ICG injection, V1 fluoresced homogenously. The fluorescence of V2 and V3 varied. Without extrinsic compression, these segments appeared as noncontiguous hot spots because the VA runs freely in a periosteal sheath surrounded by a venous plexus that attenuates the fluorescent light. Hot spots corresponded to areas where the artery neared the surface. With extrinsic compression, VA enhanced homogenously because it was pushed against the periosteal layer. During the late phase, the V1 signal was attenuated, whereas the venous plexus surrounding V2 and V3 enhanced homogeneously, thereby masking the VA itself. Near-infrared ICG videoangiography helped to confirm VA patency during transposition and rerouting but was not helpful during VA exposure because the periosteal sheath must already be exposed to detect the VA or its surrounding plexus. After exposure, videoangiography can help to determine the position of the VA within its periosteal sheath.
CONCLUSION: Videoangiography can be used to provide information about the patency of the VA and its location within the periosteal sheath to prevent injury during resection of tumor adherent to the periosteal sheath.