Magnetic Source Imaging In The Value Of Preoperative Localization Diagnosis Of Focal Cortical Dysplasia

Objective:The purposes of this study were to evaluate the diagnosticvalue of magnetic source imaging(MSI)、 video electroencephalography(VEEG) and combination of those tests in the Preoperative assessment offocal cortical dysplasia （FCD）， and to analysis the specificities andsensitivities and predictive values of Preoperative results of those tests.Methods:The research objects were82patients between February2006and June2012，who were FCD patients with intractable epilepsy, Malepatients were58cases, Female patients were24cases; age at time of surgeryranging from3years to35years,mean,21.00±6.50years. age at time of thefirst time ranging from0.17years to29.00years,mean10.46±7.17years.Course of the disease ranging from0.5years to21.00years,mean9.6±5.17years.In according to2011ILAE Diagnostic Methods, these patients hadbeen separated into FCD type I、FCD type II、FCD type Ⅲ.The patients wereundergone presurgical assessments which included MSI、 VEEG andelectrocorticography（ECoG）inter-surgical and subsequent operation.Theconsistency of localization between pre-and inter-surgical was observed. Forpatients who underwent resective surgery, postoperative seizure control wasalso recorded based on the Engel criteria.By chi-square test, the accuracy andpredictive value of noninvasive Preoperative tests were evaluated.Results：182patients were grouped into FCD type I group、FCD type IIgroup、FCD type Ⅲ group,and the numbers of patients in the three groupswere36、30and16, respectively.2In the comparison of MSI and ECoG, the results were consistent in the57cases(69.51%), the results were the partial consistent in the14cases(17.07%), the results were inconformity in the11cases（13.42%）.Theconsistent results of MSI and ECoG，the patients were assessed to the effect of surgery,46cases of57cases reached Engel Class Ⅰ，3cases reached EngelClass Ⅱ，4cases reached Engel Class Ⅲ，4cases reached Engel Class IV.3In the comparison of VEEG and ECoG, the results were consistent inthe43cases(44.19%), the results were the partial consistent in the33cases(40.24%), the results were inconformity in the6cases（7.32%）。Theconsistent results of VEEG and ECoG，the patients were assessed the effect ofsurgery,27cases of43cases reached Engel Class Ⅰ，4cases reached EngelClass Ⅱ，7cases reached Engel Class Ⅲ，5cases reached Engel Class IV.4In the comparison of MSI—VEEG(the consistent of VEEG and MSI)and ECoG，the results were consistent in the27cases(90.00%), the resultswere the partial consistent in the2cases(6.66%), the results were not theconsistent in the1cases（3.34%）。The Consistent results of MSI-VEEG andECoG，the patients were assessed the effect of surgery,23cases of27casesreached Engel Class Ⅰ，1cases reached Engel Class Ⅱ，2cases reachedEngel Class Ⅲ，1cases reached Engel Class IV.5The concordant rates of MSI、interictal VEEG and MSI-VEEG withECoG were69.51%、44.19%、90%,respectively. Chi-square test revealed thatstatistically significant differences were found, when the MSI and VEEGresults were concordant,the concordant rate with ECoG was the highest oneas90%.6By chi-square test, the accuracy and predictive value of noninvasivepresurgical investigations are evaluated， which are MSI、 VEEG andMSI—VEEG test， Chi-square test revealed that statistically significantdifferences were found between MSI and VEEG、between VEEG and MSI—VEEG（P＜0.05），no statistically significant differences were found betweenMSI and MSI—VEEG(P＞0.05).7The sensitivities of MSI test was80.70%，the specificities of MSI testwas52.00%；The sensitivities of VEEG test was62.79%, the specificities ofVEEG test was20.51%.Conclusions:1The sensitivities and specificities of MSI were superior tothe sensitivities and specificities of inter-ictal VEEG. 2The concordant rates of MSI with ECoG exceeded to the concordantrates of VEEG with ECoG，when MSI test was the concordant with ECoG,the post-surgical seizure free might be positively predicted. When MSI testwas the concordant of VEEG，the result was with ECoG highest consistency,superior to MSI and VEEG, respectively.3When MSI test was the concordant with VEEG, the predictive value ofthe postoperative improvement was no statistical difference with single MSItest，but was statistical difference with single VEEG and was superior toVEEG.4The surgical treatment of FCD type II was better than FCD typeI.There were no statistically significant differences of surgical outcomebetween FCD I and FCD III、between FCD II and FCD III.