ENYS   25968
UNIDAD EJECUTORA DE ESTUDIOS EN NEUROCIENCIAS Y SISTEMAS COMPLEJOS
Unidad Ejecutora - UE
artículos
Título:
Two types of ictal phase-amplitude couplings in epilepsy patients revealed by spectral harmonicity of intracerebral EEG
Autor/es:
DELLAVALE, DAMIÁN; VELARDE, OSVALDO MATÍAS; CÁMPORA, NURIA; MATO, GERMÁN; URDAPILLETA, EUGENIO; KOCHEN, SILVIA
Revista:
CLINICAL NEUROPHYSIOLOGY
Editorial:
ELSEVIER IRELAND LTD
Referencias:
Año: 2020 vol. 131 p. 1866 - 1885
ISSN:
1388-2457
Resumen:
Objective: Spectral harmonicity of the ictal activity was analyzed regardingtwo clinically relevant aspects, (1) as a confounding factor producing ?spurious? phase-amplitude couplings (PAC) which may lead to wrong conclusions about the underlying ictal mechanisms, and (2) its role in how good PAC is in correspondence to the seizure onset zone (SOZ) classification performed by theepileptologists. Methods: PAC patterns observed in intracerebral electroencephalography (iEEG)recordings were retrospectively studied during seizures of seven patients withpharmacoresistant focal epilepsy. The time locked index (TLI) measure wasintroduced to quantify the degree of harmonicity between frequency bands as-sociated to the emergence of PAC during epileptic seizures.Results: (1) Harmonic and non harmonic PAC patterns coexist during the seizure dynamics in iEEG recordings with macroelectrodes. (2) Harmonic PACpatterns are an emergent property of the periodic non sinusoidal waveform con-stituting the epileptiform activity. (3) The TLI metric allows to distinguish the non harmonic PAC pattern, which has been previously associated with the ictal core through the paroxysmal depolarizing shifts mechanism of seizure propagation.Conclusions: Our results suggest that the spectral harmonicity of the ictal activity plays a relevant role in the visual analysis of the iEEG recordings performed by the epileptologists to define the SOZ, and that it should be considered for the proper interpretation of ictal mechanisms.