Intraoperative real-time identification of abnormal vessels within the bright field by superselective arterial injection of saline and its slow-motion recording using a high frame rate digital camera during surgical treatment of spinal arteriovenous shunts: technical note

The usefulness of superselective arterial injection of indocyanine green (SAI-ICG) during the surgical treatment of a spinal arteriovenous shunts (AVSs) has occasionally been reported. However, SAI-ICG lacks the temporal resolution for recording rapid blood flow. The authors found that SAI of saline (SAIS) via a microcatheter renders the vessels transparent because of the replacement of intravascular blood with saline. By combining SAIS with SAI-ICG, they were able to identify abnormal vessels in the bright field during the surgical treatment of spinal AVS. Furthermore, they performed slow-motion video recording of blood flow in abnormal vessels by mounting a high frame rate (HFR) digital camera on the microscope eyepiece during SAIS. In this paper, the authors present two cases of patients with spinal AVSs. The first patient had a cervical dural arteriovenous fistula, and the second had a thoracic spinal arteriovenous malformation. SAIS delineated abnormal vessels within the bright field in real time in both cases. HFR video was recorded in the second case during SAIS. The slow-motion video showed a smooth and seamless motion of the blood flow in the feeding artery, which facilitated an understanding of the blood flow direction.