The Role of Indocyanine Green Videoangiography in Intramedullary Spinal Cord Tumor Surgery: Focus on Lesion Localization Accuracy.

Intramedullary spinal cord tumors/lesions are rare, but they present significant surgical challenges owing to the high risk of spinal cord injury during myelotomy. Conventional techniques are often limited by positional discrepancies and anatomical variations. Indocyanine green videoangiography provides real-time fluorescence imaging of the lesion vasculature. This study aimed to evaluate the safety and efficacy of intraoperative indocyanine green videoangiography and to determine which pathological subtypes are most amenable to this technique. We enrolled patients with intramedullary spinal cord tumors, excluding those with hemangioblastoma. A 2-step approach was used for lesion localization: initial delineation using conventional methods, followed by indocyanine green videoangiography, in which indocyanine green was administered intravenously, and lesion boundaries were re-marked using fluorescence imaging. The outcome measure was the prediction error distance between conventional localization and indocyanine green videoangiography localization, and the impact of lesion characteristics on localization accuracy. This study included 15 patients with intramedullary spinal cord tumors. The mean prediction error distance was 3.63 mm for the conventional method and 2.77 mm for indocyanine green videoangiography. The mean prediction error distance difference between the 2 methods was 0.87 mm (p = 0.047). Tumor size correlated with greater reductions in prediction error distance using indocyanine green videoangiography (height, p = 0.005). Larger tumors (23.4 mm in height) tended to demonstrate a mean prediction error distance reduction of 2.0 mm (p = 0.085). Minor adverse events that could be related to indocyanine green videoangiography were observed in 3 cases, all of which resolved spontaneously. Intraoperative indocyanine green videoangiography performed before myelotomy may improve the accuracy of tumor localization with minimal risk in patients with intramedullary spinal cord tumors/lesions. It might be particularly effective at minimizing errors in large intramedullary spinal cord tumors. By reducing unnecessary myelotomy, indocyanine green videoangiography may improve surgical outcomes.