Brain tumor surgery in so-called "eloquent" brain areas aims to remove as much tumor as possible while preserving neurological functions. Standard surgical planning typically focuses on discrete, anatomically defined cortical regions. However, modern neuroscience demonstrates that most brain functions arise from distributed networks of interconnected areas rather than isolated spots - a concept that standard navigation tools do not fully capture.

The CORTEX study evaluates a surgical workflow - termed "connectome-guided network-based navigation" - in which advanced diffusion MRI processing is used to reconstruct patient-specific maps of white matter pathways and large-scale brain networks. These maps are imported into a clinical neuronavigation system to guide preoperative planning and intraoperative decision-making for patients with gliomas or brain metastases in eloquent regions.

The primary aims are to determine how often network-based information leads to meaningful changes in surgical strategy compared with conventional anatomy-based planning, and to assess early neurological outcomes. Secondary objectives include characterizing the extent of tumor removal, the proximity of the resection to critical white matter tracts, and the feasibility of implementing this pipeline in a high-volume clinical setting.