Technique for intraoperative monitoring of corticospinal tract integrity using an electrode with a dynamic balloon

Aim. To present a technique for continuous monitoring of corticospinal tract integrity using an electrode with a dynamic balloon, examine the advantages and disadvantages of the selected and alternative monitoring techniques.

Materials and methods. At the 1^st stage, an electrode combined with a dynamic balloon was prepared. At the 2^nd stage, continuous monitoring of the corticospinal tract using direct stimulation of the cortex using ballon grid during the main stage of cerebral surgery was performed. At the 3^rd stage, interpretation of the obtained neurophysiological responses was performed.

Results. The presented technique of continuous monitoring of the integrity of the corticospinal tract through direct cortical stimulation using the developed device prevents false response decreases which significantly helps with the interpretation of the obtained results and increases information value of the technique. The described technique is based on the presented clinical observations of intracerebral tumor resection, as well as microsurgical aneurysm clipping using the technique. During surgery, no false decrease of the neurophysiological signal amplitude was observed due to dynamic ballon inflation and maintenance of close contact between the electrode and the surface of the brain. A surgery performed using this technique allowed to achieve a favorable neurological outcome in a patient in the postoperative period.

Conclusion. The presented device allows to perform continuous neuromonitoring using direct cortical electrostimulation with a strip electrode at any level of brain retraction. The technique decreases the risk of primary and secondary injury of the corticospinal and corticobulbar tracts which increases safety of neurosurgical intervention and decreases risks of neurological complications.

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