Archives of Neurosurgery

Corresponding Author

Enrique de Font-Réaulx

Document Type

Case Report


Background: Active Functional Mapping (AFM) is the gold standard method for localizing cortical and subcortical brain functional areas and tracts. By definition, it requires direct application of controlled electrical stimuli under established protocols. Nevertheless, it entails inherent risks, such as causing intraoperative seizures. On the other hand, Passive Functional Mapping (PFM) doesn´t require electrical stimulation of the nervous system. PFM is based on the knowledge that brain metabolism generates different electromagnetic radiation patterns depending on its metabolism, that are invisible to the human eye, but infrared thermographic cameras can show those changes related to brain activity without the use of special light or dyes. Surgical Technique: We describe the technique and results with adherence to the care guidelines, of a single case of awake epilepsy surgery with AFM and a new method for performing PFM, developed by the authors. Case Presentation: Using an infrared thermographic camera, we detected that the basal cortical temperature increases 2.8 °C while moving the contralateral face, and 2.4 °C while moving the contralateral hand, in their respective primary cortex motor areas as confirmed by AFM. Discussion: The infrared thermographic camera allows visualization of the electromagnetic radiation of the brain, without the use of dyes or special lighting in real-time, according to different metabolic conditions related to resting or activation states. Conclusion: This new PFM technique should be investigated in a clinical trial, in order to establish its sensibility and specificity.

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Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.

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