Indocyanine green videoangiography for spinal cord hemangioblastoma
As vascular tumors, intramedullary hemangioblastomas are associated with significant intraoperative blood loss, making them particularly challenging clinical entities. The use of intraoperative indocyanine green or other fluorescent dyes has previously been described to avoid breaching the tumor capsule, but improved surgical outcomes may result from identifying and ligating the feeder arteries and arterialized draining veins.
Molina et al. presented a written and media illustration of a technique for intraoperative indocyanine green use in the en bloc resection of intramedullary hemangioblastoma 1).
A 36-year-old female with a spinal hemangioblastoma located in the anterior cervical spinal cord presented with a long-standing history of motor weakness of the right upper extremity. Magnetic resonance imaging revealed a large multilevel extensive syrinx and a focal intramedullary enhanced tumor at the C6 level. Angiography showed that the main feeder to the tumor was the left radicular artery (C8), which originated from the thyrocervical trunk, penetrated the dura mater, and branched both rostrally and caudally into the anterior spinal artery (ASA). Three-dimensional computer graphic images showed the tumor was located in the anterior part of the spinal cord, adjacent to and supplied by the ASA. The planned anterior surgical approach involved a total corpectomy of C6 and partial corpectomies of C5 and C7. The tumor was entirely removed despite multiple adhesions, and was successfully freed from the ASA. Patency of the ASA was confirmed utilizing intraoperative indocyanine green videoangiography. Intraoperatively, no monitoring changes were encountered. The pathological diagnosis was of a hemangioblastoma. No postoperative deficit occurred.
An anterior approach for the resection of an anteriorly located intramedullary spinal hemangioblastomas was successfully accomplished in this case 2).
A 36-year-old female suffered progressive paresthesia of both lower extremities for 12 months and gait disturbance for 2 weeks. A neurological examination revealed T10 myelopathy. Magnetic resonance imaging (MRI) of the thoracic spine showed an intramedullary tumor at the T8 level and severe spinal cord edema with a flow void in the extended dorsal spinal veins. Spinal angiography showed a hemangioblastoma at the T8 level, with two main feeders and minor feeders.
She underwent total resection of the tumor by a posterior approach. During the intraoperative ICG videoangiography, temporary arterial occlusion of the two main feeders and FLOW(®)800 analysis enabled clear understanding of the vasculature, especially of the two minor feeders. At the 9-month follow-up, her neurological manifestation was partially resolved, and post-operative MRI showed total removal of the tumor and disappearance of the spinal cord edema.
Temporary clipping of the main feeders during intraoperative ICG videoangiography is very useful for easily determining the minor feeding arteries, and helpful for maintaining normal perfusion of the spinal cord in spinal hemangioblastoma surgery. Furthermore, the FLOW 800 analysis, especially the false color-coded variation, increased our understanding of the hemodynamics 3).
Seven patients with an SH underwent resection with the assistance of intraoperative ICG videoangiography. The ICG videoangiography images were analyzed, and the preoperative, intraoperative, and postoperative images were compared. ICG videoangiography clearly revealed the feeding arteries and enlarged draining veins and assisted in defining the tumor borders in five of the seven patients (patients one, two, four, five, and seven). By contrast, patient three had a devascularized residual tumor located deep in the spinal cord parenchyma, which did not take up the fluorescent dye and therefore was not visualized by ICG videoangiography. In addition, in patient six, only the draining veins could be visualized in the ventrolateral tumor, because it was covered by the spinal cord parenchyma. Six tumors were completely removed, and one was partially removed. None of our patients had significant neurological deterioration after surgery. ICG videoangiography provided real-time information about the tumor vasculature during surgery for SH and aided in intraoperative decision-making. However, for deep tumors and ventral tumors, the benefits of this technique might be limited 4).
A case of spinal haemangioblastoma treated with the aid of intraoperative ICG-VAG and the Flow 800 software. The use of the Flow 800 allowed the surgeon to detect, at a glance, minimal changes in the vascular supply during the dissection. The colour-coded images generated by the Flow 800 increase the ICG-CAG sensitivity, improving the capability to detect changes in vascular patterns 5).