# Intraoperative Visual Field Assessment in Parietal Glioma Resection and the Role of Virtual Reality Headset-Based Mapping

## TL;DR

This review explores how virtual reality and intraoperative techniques help protect vision during brain tumor surgery in the parietal lobe.

## Contribution

The paper highlights the novel use of VR headsets for visual pathway mapping during awake craniotomy for parietal glioma resection.

## Key findings

- VR-based brain mapping improves preoperative planning and intraoperative monitoring for visual pathway preservation.
- Awake craniotomy with sensory mapping reduces postoperative visual field deficits in parietal glioma surgery.
- Intraoperative ultrasound and MRI tractography are effective tools for preserving functional pathways during resection.

## Abstract

The aim of this literature review is to summarize techniques used to prevent postoperative visual pathway complications during parietal glioma resection involving optic radiations, focusing on the use of virtual reality (VR) headsets during awake patient surgery.

We searched the Medline database for literature between the years 1970 and 2024. Only results that included the use of awake craniotomy for sensory mapping were included for evaluation. The search was limited to studies published in English and humans as subjects. Only studies that reported patient groups treated with either parietal glioma surgery under general anesthesia or awake conditions were included. Articles describing deep brain stimulation as the therapy were excluded because the primary focus of this literature review is on techniques such as VR and intraoperative mapping, which aim to preserve or protect the integrity of the visual pathways during glioma resection involving the optic radiations. The variables initially selected for analysis included the length of surgery, length of hospital stay, extent of resection, cost, mortality, and neurological morbidity. Cost was later removed from the studied variables because too few studies reported it. No commentaries or reviews were included.

Gliomas are the most common primary brain tumors, located mainly in the cerebral cortex. Of them, some are found in the parietal lobe, which is a convergence area for multiple stimulus integrations. After surgical resection of this lobe, patients may develop postoperative verbal, linguistic, and visual field deficits. The gold standard treatment for these tumors is surgical resection. The main technique to preserve functional pathways is by intraoperative monitoring, for which different tools have been developed in the past years.

Surgeons can test and preserve important tracts, such as the visual pathway. Intraoperative ultrasound has been shown to be an excellent, accessible, and affordable intraoperative monitoring tool. Magnetic resonance imaging-based tractography and VR-based brain mapping allow not only intraoperative monitoring, but also create a preoperative plan by demarcating the structures and margins of the tumor prior to and during surgery, increasing the success rate in maximum resection.