Do we Need to Wake Patients up during Cortical Surgery?


  • Lorena Vega-Zelaya Clinical Neurophysiology, Hospital Universitario de la Princesa, Madrid, Spain
  • Rafael G. Sola Hospital Nuestra Señora del Rosario, Madrid, Spain
  • Paloma Pulido Hospital Nuestra Señora del Rosario, Madrid, Spain
  • Jesús Pastor Clinical Neurophysiology, Hospital Universitario de la Princesa, Madrid, Spain



Anaesthetized surgery, awake surgery, cortical mapping, cortico-cortical evoked potentials, intraoperative neurophysiological monitoring.


In recent years, a renewed fashion for awake surgery has appeared. In spite of its undoubted utility for scientific research, this technique has several limitations and flaws, usually not debated by parts of the scientific community.

We will discuss the aims and limitations of cortical surgery, especially the points relevant to protecting the patient. These objectives should define the guidelines that direct clinical practice. We will review the awake technique as well as various tools used in intraoperative neurophysiological monitoring (IONM) to explore and monitor several cortical functions during long surgeries. The main topics discussed include electrocorticography (ECoG) and cortically recorded evoked potentials (EP), including somatosensory, visual and auditory. Later, we will discuss methods to identify and survey motor functions as motor-evoked potentials, although they are elicited trans-cranially. Finally, we will briefly discuss a promising technique to monitor some language functions in anaesthetized patients, such as cortico-cortical evoked potentials (CCEP). We will address in depth some technical questions about electrical stimulation whose full relevance are not always considered.

Finally, we will discuss why, in the absence of empirical facts showing unequivocal superiority in post-surgical outcome, we have to awaken patients, especially when an alternate possibility exists without worst clinical results, as is the case for IONM.


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How to Cite

Lorena Vega-Zelaya, Rafael G. Sola, Paloma Pulido, & Jesús Pastor. (2018). Do we Need to Wake Patients up during Cortical Surgery? . Journal of Cancer Research Updates, 7(3), 84–96.