| ObjectsThe paper attempted to to examine the characteristics of the memory loss in patientswith temporal lobe epilepsy(TLE)，explore correlation between memory and protonmagnetic resonance spectroscopy (~1H-MRS)-identified hippocampal metabolites in TLEpatients, and discuss reliability and sensitivity of~1H-MRS values for assessing memoryfunctions.MethodsA total of57TLE patients and20controls underwent memory tests and1H-MRSinvestigation. The TLE patients were divided into left TLE group(L-TLE，n=24)， rightTLE group(R-TLE，n=17)and bilateral TLE group(B-TLE，n=16)according to EEG and1H-MRS examination outcome. To explore correlation between memory functions and1H-MRS values, and correlation between clinical variables and1H-MRS values.Results1. The TLE groups performed significantly worse than controls (p<0.01) on theappointed word recall, verbal paired associates, familiar picture recall and portraitassociates recognition tests. On the appointed word recall test, L-TLE group performedsignificantly worse than R-TLE group(P=0.01), no statistical difference between L-TLEand B-TLE groups. On the complex figure recognition test, R-TLE group performedsignificantly worse than L-TLE group(P=0.012), no statistical difference betweenR-TLE and B-TLE groups. There were no statistical differences between the TLEgroups on verbal paired associates, familiar picture recall and portrait associatesrecognition tests.2. The TLE patients, compared with controls, NAA/(Cr+Cho) ratios were decreased in both hippocampus(left NAA/(Cr+Cho)：χ~2=56.21，P=0.00；right NAA/(Cr+Cho)：χ~2=45.81，P=0.00). There were more severe NAA/(Cr+Cho) ratios decrease in the lefthippocampus compared with the contralateral hippocampus in L-TLE group(Z=-4.298，P=0.000), and more severe NAA/(Cr+Cho) ratios decrease in the righthippocampus compared with the contralateral hippocampus in R-TLE group(Z=-3.632，P=0.000).3. In L-TLE group, bilateral NAA/(Cr+Cho) ratios were correlated with the scores ofappointed word recall, verbal paired associates and portrait associates recognition tests,the contralateral NAA/(Cr+Cho) ratios were correlated with the scores of familiarpicture recall (r=0.520, p=0.009)and complex figure recognition tests(r=0.599, p=0.002).In R-TLE group, bilateral NAA/(Cr+Cho) ratios were correlated with the scores offamiliar picture recall, complex figure recognition and portrait associates recognitiontests, the contralateral NAA/(Cr+Cho) ratios were correlated with the scores ofappointed word recall test(r=0.634, p=0.006). In B-TLE group, bilateral NAA/(Cr+Cho)ratios were correlated with the scores of all the tests.4. There were negative correlations between bilateral hippocampal NAA/(Cr+Cho)ratios and age in controls. There were negative correlations between hippocampalNAA/(Cr+Cho) ratios and demographic information (age at seizure onset, duration ofillness and frequency of seizure) in L-TLE and R-TLE groups. In B-TLE groups, therewere no correlations between hippocampal NAA/(Cr+Cho) ratios and demographicinformation, but a trend of negative correlation existed between NAA/(Cr+Cho) ratiosand frequency of seizure.Conclusions1. The dominant side or non-dominant side of TLE could be associated with widespreadmetabolic abnormalities in bilateral hippocampus. The NAA and NAA/(Cr+Cho) ratiosloss could be primary for the dominant side in TLE.2. Those poor performance showed the extensive memory function damage in L-TLE and R-TLE groups. The L-TLE patients had the lowest scores on pure verbal memorytest and the R-TLE patients showed the worst performance on pure visual memory test.3. The hippocampal NAA/(Cho+Cr) ratios were associated with the scores of memorytests in TLE patients.4. There were negative correlations between hippocampal NAA/(Cho+Cr) ratios anddemographic information (age at seizure onset, duration of illness and frequency ofseizure) in L-TLE and R-TLE groups. In B-TLE groups, there were no correlationsbetween hippocampal NAA/(Cr+Cho) ratios and demographic information, but a trendof negative correlation existed between NAA/(Cr+Cho) ratios and frequency of seizure. |
