Abstracts

Rationale: Magnetic Resonance Imaging and Neuropsychological tests are two sources of information for diagnosis of mesial temporal lobe epilepsy (mTLE) and prediction of response to surgery in standard practice. The hippocampus is a part of the middle arc of the limbic system that strongly contributes to the functionality of the temporal lobe. Furthermore, considering the fact that the temporal lobes are involved in the retention of visual memories, processing sensory input, comprehending language, storing new memories, emotion, and deriving meaning, all together would make the hippocampus and temporal lobes of epileptic brains along with Neuropsychological or behavioral information well deserved to be studied further. This study investigates the correlation between MRI information and behavioral test scores of 67 mTLE patients who had undergone surgical resection of their mesial temporal structure and achieved an Engel class I outcome.Methods: In this study, the T2-FLAIR images of 67 mTLE patients along with their 14 different neuropsychological test scores were studied. This study first introduces a novel statistical-based hypothesis testing method for regional detection and quantification of hyper-intensity in FLAIR MRI of the left and right hippocampi and then investigates the relationship between the regional-based hyper-intensity profile of FLAIR in hippocampi and the functional information extracted from a set of pre-surgical behavioral tests of 67 mTLE patients. The left and right hippocampi of each patient were subdivided into 3 segments: head, body, and tail. Using Welch’s t-test and 3 hypotheses, T2-FLAIR hyper-intensity (T2FHI) of each segment was calculated and the results were compared to the scores of the following tests: Boston Naming Test (BNT), Wechsler Non-Verbal Delayed Memory (WNVDM), California Verbal Learning Test Long Delay Free Recall (CVLTLDFR), Rey-Osterreith Non-Verbal Immediate Memory (RONVIM), Non-Verbal IQ (NVIQ), Wechsler Verbal Delayed Memory (WVDM), California Verbal Learning Test Recognition (CVLTR), Verbal IQ (VIQ), Full Scale IQ (FSIQ), Wechsler Non-Verbal Immediate Memory (WNVIM), Rey-Osterreith Non-Verbal Delayed Memory (RONVDM), Wechsler Verbal Immediate Memory (WVIM), California Verbal Learning Test Total (CVLTT), and WADA.Results: As shown in Tables 1, correlation study reveals that for the right sided patients only 1 neuropsychological test (CVLTR, r=-0.5939, p=0.0073) might be correlated with the T2FHI and for the left sided patients only 6 neuropsychological tests (NIVQ, VIQ, FSIQ, WADA Left test, RONVMI, CVLTR) might be correlated with the T2FHI information.Conclusions: This study assess and conduct a correlative study to reveal the relationship between different neuropsychological tests across multiple cognitive domains and the FLAIR MRI of hippocampal head, body, and tail sub-regions in mTLE patients.Our results present evidence that neuropsychological impairments might be correlated with the T2-FLAIR Hyper Intensity of the hippocampal sub regions which can be due to the sclerosis abnormalities.