~1H-Magnetic Resonance Spectroscopy And Diffusion-weighted Image In Primarily Generalized Tonic-clonic Seizure Epilepsy: Initial Experience

ObjectiveTo detect the metabolites(NAA,Cho,Cr,Glu,Gln) and ADC values in the thalamus,basal ganglia and insular lobe system of patients with PGTCS by using 1H-MRS and DWI,the aim was to analyse pathologic physiology in brain,discuss the significance of the change in the onset of PGTCS,and provide a new exploratory method for clinical research.MethodsThirty patients of PGTCS and twenty matched healthy volunteers were studied. metabolites of two-sides thalamus,basal ganglia and insular lobe were collected by 1H-MRS,and NAA,Cr,Cho were acquired with half-quantitative analysis.The colour-coded imaging which relative signal intensity of metabolites(NAA/Cr,NAA/(Cho+Cr)) was amalgamated to T1WI imaging to measure NAA/Cr,NAA/(Cho+Cr) signal intensity in thalamus,basal ganglia and insular lobe areas.The severe degree of seizure was evaluated by seizure severity scale(NHS3),then observe the correlation of the ratio of NAA/Cr,NAA/(Cr+Cho) and the scores of NHS3.DWI was performed in 20 patients with PGTCS,ADC values were observed in corresponding areas.ResultsThe NAA/Cr level of both thalamus in the group of PGTCS was significantly low,The ratio of NAA/(Cr+Cho) was either lower than the normal control group(P≤0.05),but there was no difference between the two groups in basal ganglia and insular lobe.Glx/Cr levels in left/right thalamus showed lower,but there were statistical differences in left thalamus between the PGTCS and control healthy group(P=0.0094).Thcre were no statistical differences about Glx/Cr in basal ganglia and insular lobe between two groups(P＞0.05).Through the amalgamation of the colour-coded imaging and the routine MRI imaging,the difference of the signal intensity of the ratio of NAA/Cr,NAA/(Cho+Cr) in thalamus between two groups would be straightly detected.There was negative correlation between the ratio of NAA/Cr,NAA/(Cr+Cho) and the scores of NHS3.The ADC values of two sides thalamus,basal ganglia and insular lobe in the group of PGTCS were significantly higher than that of the controls(P≤0.05).ConclusionsThe change of PGTCS in thalamus was the loss of neuron and hyperplasia of colloid cell,The abnormality of NAA/Cr and NAA/(Cho+Cr) in thalamus with PGTCS might indicate that the thalamus was the correlated encephalic region of epileptic seizures or injured cerebral zone caused by long time seizures.The MRS could reflect the injure degree exactly during the onset interval.The ADC values could sensitively reflecte pathologic physiology that there was the increase of water diffusion during the interval of seizure, moreover,the abnormality not only exists thalamus,but also involve acroteric structure,as basal ganglia and insular lobe.