Abstract

  This case report illustrates the benefit of utilizing Intraoperative Neurophysiological Monitoring (IONM) during the resection of an optic nerve lesion. A multimodality IONM utilized Electroretinogram (ERG), Visual Evoked Potentials (VEP) and Electroencephalography (EEG).

  A 47-year-old female presented with left intracranial meningioma and decreased vision in the right eye. An MRI showed tumor attached to the left optic nerve and posteriorly displacing optic nerve and chiasm to the right. After induction and patient positioning, LED goggles were placed and secured on both eyes for performing VEP. The VEP responses were absent at baseline due to the inhalational agent. After switching to Total Intravenous Anesthesia (TIVA), ERG responses were recorded bilaterally. Baseline VEP and EEG recordings were obtained with good left VEP and absent right VEP responses. During tumor resection there was sudden decrease in left VEP responses. Retractors were removed immediately and the responses came back to baseline within few minutes. The tumor was resected without any loss of vision intraoperatively.

  The patient noticed an improvement in her right eye four days post-operatively. One month post-operatively she continued to feel improvement. In this patient, the VEP was used effectively for the prevention of any loss of vision intra-operatively. The neurophysiological monitoring utilizing ERG and VEP helped prevent any further loss of vision and directing the surgeon intra-operatively.

Keywords: Electroretinogram (ERG); Visual Evoked Potentials (VEP); Electroencephalography (EEG); Intraoperative Neurophysiological Monitoring (IONM); Tumor

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Citation

Citation: Faisal R Jahangiri., et al. “Protecting the Visual Pathways During Optic Nerve Surgery Using Intraoperative Visual Evoked Potentials (VEP)”. Acta Scientific Clinical Case Reports 1.2 (2020): 03-08.

Copyright

Copyright: © 2020 B Faisal R Jahangiri., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.