Ictal technetium-99 m ethyl cysteinate dimer single-photon emission tomographic findings in epileptic patients with polymicrogyria syndromes: a subtraction of ictal-interictal SPECT coregistered to MRI study.
OBJECTIVE
To describe the ictal technetium-99 m-ECD SPECT findings in polymicrogyria syndromes (PMG) during epileptic seizures.


METHODS
We investigated 17 patients with PMG syndromes during presurgical workup, which included long-term video-electroencephalographic (EEG) monitoring, neurological and psychiatry assessments, invasive EEG, and the subtraction of ictal-interictal SPECT coregistered to magnetic resonance imaging (MRI) (SISCOM).


RESULTS
The analysis of the PMG cortex, using SISCOM, revealed intense hyperperfusion in the polymicrogyric lesion during epileptic seizures in all patients. Interestingly, other localizing investigations showed heterogeneous findings. Twelve patients underwent epilepsy surgery, three achieved seizure-freedom, five have worthwhile improvement, and four patients remained unchanged.


CONCLUSIONS
Our study strongly suggests the involvement of PMG in seizure generation or early propagation. Both conventional ictal single-photon emission computed tomography (SPECT) and SISCOM appeared as the single contributive exam to suggest the localization of the epileptogenic zone. Despite the limited number of resective epilepsy surgery in our study (n = 9), we found a strong prognostic role of SISCOM in predicting surgical outcome. This result may be of great value on surgical decision-making of whether or not the whole or part of the PMG lesion should be surgically resected.
Wichert-Ana
Lauro
L
Department of Neurology, University of São Paulo, Ribeirão Preto, Brazil. lwichert@rnp.fmrp.usp.br
de Azevedo-Marques
Paulo Mazzoncini
PM
Oliveira
Lucas Ferrari
LF
Fernandes
Regina Maria França
RM
Velasco
Tonicarlo Rodrigues
TR
Santos
Antonio Carlos
AC
Araújo
David
D
Kato
Mery
M
Bianchin
Marino Muxfeldt
MM
Sakamoto
Américo Ceiki
AC
D000293:Adolescent; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D002648:Child; D003545:Cysteine / Q000031:analogs & derivatives*; D004827:Epilepsy / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D054220:Malformations of Cortical Development / Q000175:diagnosis*; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D013382:Subtraction Technique; D013577:Syndrome; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C059659:technetium Tc 99m bicisate; D003545:Cysteine