Navigated three-dimensional intraoperative ultrasound-guided awake resection of low-grade glioma partially infiltrating optic radiation.

We report a case of awake resection of temporal low-grade glioma infiltrating the optic radiation (OR). The OR was localized by direct electrical stimulation (DES) and the tumor was delineated by navigated intraoperative 3D ultrasound. Ultrasound artifacts were eliminated by 3D-ultrasound data acquisition with a miniature probe inserted into the resection cavity. A total of 97 % resection was achieved, and small tumor portion involving OR was intentionally left in place. Functional result was partial quadrantanopia instead of more profound visual deficit, which would follow gross-total resection. To our knowledge, DES of OR was reported once; the aforementioned method of ultrasound artifact elimination has not been reported before.