Use of a New Indocyanine Green Pooling Technique for Improved Visualization of Spinal Dural AV Fistula: A Single-Center Case Series.

BACKGROUND

Intraoperative indocyanine green video angiography (ICG-VAG) is a useful tool in cerebral vascular surgery. In spinal procedures such as dural arteriovenous (AV) fistula, use of ICG-VAG is limited due to lower perfusion pressure. Therefore, we developed a new pooling technique with adapted workflow to improve intraoperative visualization.

METHODS

Patients operated on spinal dural AV fistulas using ICG-VAG were prospectively included. A new workflow for ICG-VAG was applied: 1) temporary clip placement at the suspected fistula point, 2) ICG administration during 100% oxygenation, 3) ICG pooling proximal of temporary clip, 4) clip removal/observation of vascular filling. Case records, clinical data, magnetic resonance imaging, digital subtraction angiography (DSA), and clinical outcome were analyzed retrospectively.

RESULTS

A total of 11 patients (median age 68 years, average course of disease 15 months) were included. Optimized, inverted workflow resulted in considerable pooling of ICG in the supplying feeder of the AV fistula in all cases. Complete obliteration was confirmed in 10 of 11 patients by postoperative DSA. However, 1 patient had an additional, preoperative radiologically undetected small feeder that enlarged until postoperative DSA and made successful reoperation necessary. After the median follow-up of 33.2 months, the Aminoff-Logue scale was decreased in all patients, and the McCormick score (modified Rankin score) was improved in 9 (8) patients and remained stable in 2 (3) patients.

CONCLUSIONS

Procedure modification in terms of ICG pooling enabled us to detect more easily the pathologic vascular architecture. ICG-VAG is a useful adjunct in the surgical treatment of spinal dural AV fistula because it is a real-time, noninvasive, and radiation-free technique with adequate image resolution.