Interictal hyperemia correlates with epileptogenicity in polymicrogyric cortex.
OBJECTIVE
To investigate pathophysiological factors underlying the presence of interictal hyperperfusion within the limits of the polymicrogyric (PMG) cortex in epileptic patients.


METHODS
Retrospective observational study on interictal perfusion by Single Photon Emission Computed Tomography (SPECT) in 16 patients with PMG and its correlations with a number of clinical and neurophysiological variables. Patients underwent video-EEG monitoring, neurological and psychiatric assessments, invasive EEG, and the interictal SPECT coregistered to Magnetic Resonance Imaging (MRI).


RESULTS
Patients with interictal hyperperfusion within the PMG cortex had a significantly higher spike rate on interictal EEG than patients with normal perfusion. Interictal hyperperfusion was not correlated to sex, age at epilepsy onset, age at evaluation, number of seizures per month, presence of initial precipitating insult (IPI), abnormal neurological examination, EEG findings, ictal semiology, and seizure outcome. The high interictal spike rate did not correlate to a high frequency of seizures per month.


CONCLUSIONS
Our work provides further evidences for an intrinsic epileptogenesis of the PMG cortex during the interictal state, which accounts for the major role of PMG tissue in seizure generation. These results might help to increase our understanding about epileptogenesis related to the PMG cortex, providing new tools for more tailored epilepsy surgery in PMG patients.
Wichert-Ana
Lauro
L
Department of Neurology, Psychiatry and Clinical Psychology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, Brazil. lwichert@rnp.fmrp.usp.br
de Azevedo-Marques
Paulo Mazzoncini
PM
Oliveira
Lucas Ferrari
LF
Terra-Bustamante
Vera Cristina
VC
Fernandes
Regina Maria França
RM
Santos
Antonio Carlos
AC
Araújo
Whemberton Martins
WM
Bianchin
Marino Muxfeldt
MM
Simões
Marcus Vinícius
MV
Sakamoto
Américo Ceiki
AC
D000293:Adolescent; D000328:Adult; D002540:Cerebral Cortex / Q000002:abnormalities* / Q000000981:diagnostic imaging; D004569:Electroencephalography / Q000379:methods; D004827:Epilepsy / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies; D013223:Statistics as Topic; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014741:Video Recording / Q000379:methods