Surgical treatment of anterior visual pathway gliomas in children using intraoperative neurophysiological monitoring and MR tractography

Background. Surgical resection of anterior visual pathway gliomas carries a high risk of postoperative visual deficit. The goals of surgical treatment are maximum safe removal of tumor and histological verification. Diffusion tensor imaging (DTI) with reconstruction of visual pathways and intraoperative monitoring of visual evoked potentials (VEP) were proposed to reduce the risk of potential visual dysfunction. Objective. To demonstrate two cases of surgical treatment for anterior visual pathway gliomas using preoperative MR tractography of visual pathways and intraoperative VEP monitoring. Material and methods. Two patients with anterior visual pathway tumors underwent preoperative MR tractography of visual pathways. Intraoperative VEP monitoring was performed. Results. Extent of resection in both cases was determined by preoperative MR tractography and intraoperative neurophysiological monitoring of VEP. Ophthalmological status in early postoperative period demonstrated positive dynamics in the 1st patient and no changes in the 2nd patient. Conclusion. Preoperative MR tractography of visual pathways and intraoperative neurophysiological monitoring of VEP with electrophysiological identification of visual pathways may potentially enable safer tumor resection and minimize the risk of postoperative visual deficit.