Radiofrequency thermocoagulation parameters impact on lesion size during stereo-EEG

Background. Radiofrequency thermocoagulation of the epileptogenic zone via depth stereo electrodes may be an alternative to resective surgery in patients with drug-resistant epilepsy.

Aim. To determine the parameters of radiofrequency thermocoagulation that affect the lesion volume.

Materials and methods. A study was conducted using chicken egg whites. With the help of depth electrodes, lesions of different volumes were produced at different parameters. Data of two patients who underwent stereoelectroencephalography at the N.I. Pirogov National Medical Clinical Center (the size of the focus of destruction and its effect on the course of the disease) are presented as examples of the use of the method in clinical practice.

Results. The largest lesion was created at a power of 3 W for 180 seconds between adjacent contacts of one electrode. Using this technology in clinical practice allowed partial destruction of the epileptogenic zone in one case and complete destruction in the second.

Radiofrequency thermocoagulation allows to achieve seizure freedom or a reduction in their frequency and intensity in patients with drug-resistant epilepsy. The relationships we discovered between the parameters of radiofrequency thermocoagulation and the parameters of the formed lesions are similar to those presented in other works.

Conclusion. The largest lesions are formed as a result of radiofrequency thermocoagulation with lower power and longer exposure. The effectiveness of radiofrequency thermocoagulation as a treatment for epilepsy is influenced by the ratio of the lesion size and the size of the epileptogenic zone.

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