MTLE Patients (mtle + patient)

Distribution by Scientific Domains

Selected Abstracts

Facial emotion recognition impairment in chronic temporal lobe epilepsy

EPILEPSIA, Issue 6 2009
Stefano Meletti
Summary Purpose:, To evaluate facial emotion recognition (FER) in a cohort of 176 patients with chronic temporal lobe epilepsy (TLE). Methods:, FER was tested by matching facial expressions with the verbal labels for the following basic emotions: happiness, sadness, fear, disgust, and anger. Emotion recognition performances were analyzed in medial (n = 140) and lateral (n = 36) TLE groups. Fifty healthy subjects served as controls. The clinical and neuroradiologic variables potentially affecting the ability to recognize facial expressions were taken into account. Results:, The medial TLE (MTLE) group showed impaired FER (86% correct recognition) compared to both the lateral TLE patients (FER = 93.5%) and the controls (FER = 96.4%), with 42% of MTLE patients recording rates of FER that were lower [by at least 2 standard deviations (SDs)] than the control mean. The MTLE group was impaired compared to the healthy controls in the recognition of all basic facial expressions except happiness. The patients with bilateral MTLE were the most severely impaired, followed by the right and then the left MTLE patients. FER was not affected by type of lesion, number of antiepileptic drugs (AEDs), aura semiology, or gender. Conversely, the early onset of seizures/epilepsy was related to FER deficits. These deficits were already established in young adulthood, with no evidence of progression in older MTLE patients. Conclusion:, These results on a large cohort of TLE patients demonstrate that emotion recognition deficits are common in MTLE patients and widespread across negative emotions. We confirm that early onset seizures with right or bilateral medial temporal dysfunction lead to severe deficits in recognizing facial expressions of emotions. [source]

Intrinsic Ictal Dynamics at the Seizure Focus: Effects of Secondary Generalization Revealed by Complexity Measures

EPILEPSIA, Issue 2 2007
Christophe C. Jouny
Summary:,Purpose: Partial seizures (PSs) may be self-limited regional events or propagate further and secondarily generalize. The mechanisms and dynamics of secondarily generalized tonic,clonic seizures (GTCSs) are not well understood. Methods with which to assess the dynamic of those events are also limited. Methods: Seizures were analyzed from patients with intractable partial seizures undergoing monitoring with intracranial electrodes. Inclusion in this study required patients to have at least one PS and one GTCS. From >120 patients, seven patients fulfilled these criteria, three with mesial temporal (MTLE) onset seizures and four with neocortical lesional (NCLE) onset seizures. In total, 50 seizures were analyzed by using the matching pursuit (MP) method and the Gabor atom density (GAD), a measure of signal complexity derived from the MP method. Results: The GAD complexity pattern at the seizure focus for the initial ictal period is remarkably consistent in a given patient, regardless of whether secondary generalization occurs. Secondary generalization produces greater modification of seizure activity at the focus in patients with NCLE than in patients with MTLE. In seizures from four patients with NCLE, secondary generalization resulted in an average increase of 115% in complexity at the focus compared to PSs. Conclusions: GAD shows that seizure dynamics of PSs are often very stereotyped from seizure to seizure in a given patient, particularly during early ictal evolution. Secondary generalization is more likely to produce changes in the duration and dynamics at the seizure focus in NCLE patients compared with MTLE patients. These observations suggest distinct mechanisms (e.g., feedback) that are operational during secondary generalization. [source]

Decreased basal fMRI functional connectivity in epileptogenic networks and contralateral compensatory mechanisms

Gaelle Bettus
Abstract A better understanding of interstructure relationship sustaining drug-resistant epileptogenic networks is crucial for surgical perspective and to better understand the consequences of epileptic processes on cognitive functions. We used resting-state fMRI to study basal functional connectivity within temporal lobes in medial temporal lobe epilepsy (MTLE) during interictal period. Two hundred consecutive single-shot GE-EPI acquisitions were acquired in 37 right-handed subjects (26 controls, eight patients presenting with left and three patients with right MTLE). For each hemisphere, normalized correlation coefficients were computed between pairs of time-course signals extracted from five regions involved in MTLE epileptogenic networks (Brodmann area 38, amygdala, entorhinal cortex (EC), anterior hippocampus (AntHip), and posterior hippocampus (PostHip)). In controls, an asymmetry was present with a global higher connectivity in the left temporal lobe. Relative to controls, the left MTLE group showed disruption of the left EC-AntHip link, and a trend of decreased connectivity of the left AntHip-PostHip link. In contrast, a trend of increased connectivity of the right AntHip-PostHip link was observed and was positively correlated to memory performance. At the individual level, seven out of the eight left MTLE patients showed decreased or disrupted functional connectivity. In this group, four patients with left TLE showed increased basal functional connectivity restricted to the right temporal lobe spared by seizures onset. A reverse pattern was observed at the individual level for patients with right TLE. This is the first demonstration of decreased basal functional connectivity within epileptogenic networks with concomitant contralateral increased connectivity possibly reflecting compensatory mechanisms. Hum Brain Mapp 2009. 2008 Wiley-Liss, Inc. [source]

T2-Weighted and T2 Relaxometry Images in Patients with Medial Temporal Lobe Epilepsy

Ana Carolina Coan MD
ABSTRACT Purpose. Quantification of increased T2-weighted MRI signal that is associated with hippocampal sclerosis (HS) can be performed through (1) mean of hippocampal signal in single-echo T2 MRI and (2) hippocampal T2 relaxometry. It is not clear whether these two techniques are equivalent. In this study, we compare the hippocampal signal, detected by single-echo T2 quantification and by T2 relaxometry, in patients with medial temporal lobe epilepsy (MTLE). Methods. We studied magnetic resonance images from 50 MTLE patients and 15 healthy subjects. We compared the quantification of a T2 signal from single echo images to T2 relaxometry, both obtained from a manually traced region of interest (ROI) in coronal slices involving the whole hippocampus. Repeated measures ANOVA was used to evaluate the differences in the distribution of the Z -scores from single-echo T2 quantification and T2 relaxometry within subjects. Results. We observed a significant difference between the measurements obtained from single-echo T2 quantification and T2 relaxometry (P < .001). Measurements from head, body, and tail of the hippocampus were different (P=.04), with a significant interaction between anatomic location and type of measurement used (P= .008). Post hoc paired comparisons revealed that T2 relaxometry yielded greater Z -scores for the body (P= .002) and tail (P < .0001). Conclusions. For each subject with MTLE, T2 relaxometry was able to detect a higher signal in the body and tail of the hippocampus compared to single-echo T2. This is a possible indicator that T2 relaxometry is more sensitive in detecting T2 abnormalities within the body and tail of the hippocampus in patients with MTLE. [source]

FDG-PET Images Quantified by Probabilistic Atlas of Brain and Surgical Prognosis of Temporal Lobe Epilepsy

EPILEPSIA, Issue 9 2002
Sang Kun Lee
Summary: ,Purpose: This study evaluated the relation between hypometabolism, diagnosed by fluorodeoxyglucose positron emission tomography (FDG-PET), and the surgical outcome of a large and homogeneous series of cases of mesial temporal lobe epilepsy (mTLE), by using a probabilistic atlas of the human brain (statistical probabilistic anatomical maps: SPAM). Methods: Ninety-five surgically proven intractable mTLE patients and 22 age-matched controls were spatially normalized to the average brain PET template of international consortium of brain mapping (ICBM). The diagnosis of mTLE was confirmed by the presence of hippocampal sclerosis on magnetic resonance imaging (MRI) and video-EEG monitoring. Counts from normalized PET images were multiplied by the probability from 98 volumes of interest (VOIs) of SPAM. Asymmetric indexes (AIs) reflecting the severity of hypometabolism were calculated by counts of selected 12 VOIs from SPAM images in both temporal lobes. Extent of hypometabolism was determined by the number of voxels showing decreased metabolism in each VOI segmented by SPAM. Results: Of the 95 patients studied, 76 (80%) were seizure free, and 19 (20%) had postoperative seizures for the ,2-year follow-up period. No significant association between the severity of hypometabolism in each VOI of the temporal lobe and surgical outcome was identified (p > 0.05). The number of voxels showing decreased hypometabolism was not significantly different between the good- and poor-outcome groups (p > 0.05). Conclusions: Our results demonstrated that focal severity and extent of hypometabolism quantified by a probabilistic atlas of brain were not related to the surgical outcome in mTLE patients who had hippocampal sclerosis on MRI. We should develop a more localized and specified anatomic map for mTLE for further results. [source]

Temporal lobe magnetic resonance spectroscopic imaging following selective amygdalohippocampectomy for treatment-resistant epilepsy

D. C. Spencer
Objectives,,, Magnetic resonance spectroscopic imaging (MRSI) may show circumscribed or extensive decreased brain N -acetyl aspartate (NAA)/creatine and phosphocreatine (Cr) in epilepsy patients. We compared temporal lobe MRSI in patients seizure-free (SzF) or with persistent seizures (PSz) following selective amygdalohippocampectomy (SAH) for medically intractable mesial temporal lobe epilepsy (mTLE). We hypothesized that PSz patients had more extensive temporal lobe metabolite abnormalities than SzF patients. Materials and methods,,, MRSI was used to study six regions of interest (ROI) in the bilateral medial and lateral temporal lobes in 14 mTLE patients following SAH and 11 controls. Results,,, PSz patients had more temporal lobe ROI with abnormally low NAA/Cr than SzF patients, including the unoperated hippocampus and ipsilateral lateral temporal lobe. Conclusion,,, Postoperative temporal lobe MRSI abnormalities are more extensive if surgical outcome following SAH is poor. MRSI may be a useful tool to improve selection of appropriate candidates for SAH by identifying patients requiring more intensive investigation prior to epilepsy surgery. Future prospective studies are needed to evaluate the utility of MRSI, a predictor of successful outcome following SAH. [source]