Cerebral SPECT under VEEG monitoring combined with semi-quantitative analysis in localization of epileptogenic zone

Abstract

Objective To investigate the value of the cerebral blood flow SPECT used for localization of epileptogenic zone in patients with intractable epilepsy,which was performed under the videoelectroencephalogram (VEEG) monitoring combined with the semi-quantitative analysis.Methods Ccrcbral blood flow SPECT was performed under VEEG monitoring and seizures were captured either by sleep-deprived or by reducing dose or by withholding of antiepileptic drugs (AEDs).Neurogam analysis was used in the procedure of image interpretation.Results 19 inter-ictal combined with ictal images and 62 only inter-ictal images were obtained in this study.The detection rates of the pathological focus for SPECT,VEEG and MRI were 95％、98％ and 42％,respectively.There was no significant difference between SPECT and VEEG,but both methods were significant higher than MRI (x2 =52.913,P ＜ 0.001 ; x2 =59.247,P ＜ 0.001).The accordance rate of localization of pathological focus between SPECT and VEEG (69％) was significant higher than the accordance rate between SPECT and MRI (25％;x2 =26.905,P ＜0.001) and between VEEG and MRI (27％;x2 =26.905,P ＜0.001).The localization accuracy of SPECT,VEEG and MRI were 83％ 、74％ and 52％,rcspectively.Of the 14 patients who had an Engel class Ⅰ or Ⅱ outcome after surgery,there were 11 cases came from its coincidence between SPECT and VEEG.Conclusions The cerebral SPECT imaging method applied in this study was relatively simple and convenient and could play an important role in the localization of epileptogenic zone.It could be used as a routine test in patients with intractable epilepsy. Key words: Intractable epilepsy; Video electroencephalogram; Epileptogenic zone