Preoperative assessment of eloquence in neurosurgery: a systematic review

Three montages for Transcranial Electric Stimulation in predicting the early post-surgery outcome of the facial nerve functioning

“…Since there is a wide anatomic (and thus functional) variability in the individual location of the motor cortical area of the human brain (Eichert et al, 2021), a presurgical brain mapping of motor functions should be performed with functional neuroimaging techniques or transcranial magnetic stimulation (for recent reviews on topic see Sollmann et al, 2021 and Voets et al, 2022), thus improving the preoperative surgical plan. The presurgical assessment of cortical motor areas is an open issue of the utmost relevance for the surgery involving supratentorial regions of the brain (Rammelloo et al, 2023), where sparing the eloquent cortical areas is mandatory, but it would be important as well in the brainstem and skull base surgery, helping in the customization of a most reliable TES montage in each patient. However, it is not always easy to perform presurgical brain mapping, therefore, in the daily practice, the individual anatomical landmarks and skull measure are used to place electrodes for TES in a “standard” way.…”