In the Pirogov Center, it became possible to perform an additional study in patients with MR-negative form of epilepsy (there were no apparent epileptogenic foci for MRI), or in the case of several suspicious foci, when other diagnostic methods do not allow to decide which of them is epileptogenic.

This protocol includes several stages:

  1. Conducting a single-photon emission computed tomography (SPECT-CT) during an epileptic seizure;
  2. Carrying out single-photon emission computed tomography (SPECT-CT) outside of epileptic seizure;
  3. EEG monitoring during an attack;
  4. Performing the combined images of SPECT-CT (subtraction of two SPECT-CT studies), after which the obtained data are superimposed on the so-called anatomical mask (data of earlier performed MRI).

The SISCOM protocol is an important tool in the pre-surgical diagnosis of epilepsy. It is used to localize the epileptogenic zone in patients with pharmacoresistant epilepsy with an unidentified or MR negative substrate, in the presence of multiple substrates, and also in the presence of conflicting data from video EEG monitoring and MRI.

The protocol has high diagnostic value in the identification of the seizure initiation zone, it can be used to determine the locus of placement and direction of intracranial electrodes (before invasive electrodes) and, in combination with other methods of pre-surgical diagnosis, has high predictive value in evaluating the outcome of surgical treatment.

In the case of correlation of SISCOM data with the results of other pre-surgical techniques (VEEG, PET, etc.), patients are most likely to have a chance of a satisfactory outcome of surgical treatment.

Specialists can also get acquainted with the clinical observation associated with the use of the SISCOM protocol.