Value of ictal and interictal epileptiform discharges and high frequency oscillations for delineating the epileptogenic zone in patients with focal cortical dysplasia.
Clin Neurophysiol
; 129(6): 1311-1319, 2018 06.
Article
in En
| MEDLINE
| ID: mdl-29523391
ABSTRACT
OBJECTIVES:
There are different neurophysiological markers of the Epileptogenic Zone (EZ), but their sensitivity and specificity for the EZ is not known in Focal Cortical Dysplasia (FCD) patients.METHODS:
We studied patients with FCD who underwent stereoelectroencephalography (SEEG) and surgery. We marked in the SEEG (a) typical and atypical interictal epileptiform patterns, (b) ictal onset patterns, and (c) rates of ripples (80-250â¯Hz) and fast ripples (FRs) (>250â¯Hz). High frequency oscillations were marked automatically during one hour of deep sleep. Surgical outcome was defined as good (Engel I) or poor (Engel II-IV). We computed the sensitivity and, as a measure of specificity, the false positive rate to identify the EZ, and compared them across the different neurophysiological markers.RESULTS:
We studied 21 patients, 19 with FCD II. Ictal and typical interictal pattern were the markers with highest sensitivity, while the atypical interictal pattern had the lowest. We found no significant difference in specificity among markers. However, there is a tendency that FRs had the lowest false positive rate.CONCLUSION:
The typical interictal pattern has the highest sensitivity. The clinical use of FRs is limited by their low sensitivity.SIGNIFICANCE:
We suggest to analyze the typical interictal pattern first. FRs should be analyzed in a second step. If, for instance, a focus with FRs and no typical interictal pattern is found, this area could be considered for resection.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Seizures
/
Brain
/
Epilepsy
/
Malformations of Cortical Development, Group I
Type of study:
Diagnostic_studies
/
Observational_studies
Limits:
Adolescent
/
Adult
/
Child
/
Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
Clin Neurophysiol
Journal subject:
NEUROLOGIA
/
PSICOFISIOLOGIA
Year:
2018
Document type:
Article