jafar mehvari habibabadi

Temporal lobe epilepsy (TLE) is the most prevalent form of drug-resistant epilepsy with concurrent cognitive impairment. Prevention, earlier diagnosis, and personalized management of cognitive deficits in TLE require more understanding of underlying structural and functional brain Ialterations. No study has evaluated the performance of TLE patients in different cognitive domains based on their structural brain lesions.

In this study, 69 refractory TLE patients underwent magnetic resonance imaging (MRI) epilepsy protocol and several neuropsychological tests, consisting of the Wechsler adult intelligence scale-revised, Rey-Osterrieth complex figure test, verbal fluency test, digit span test, spatial span test, Wechsler memory scale-III, design fluency test, Rey visual design learning test, auditory-verbal learning test, and trail making test. MRI findings were classified into the following groups: Focal cortical dysplasia, gliosis, atrophy, mesial temporal sclerosis (MTS), tumor, vascular malformation, and other lesions or normal. Results of neuropsychological tests were compared between MRI groups using a generalized linear model with gamma distribution and log link.

Patients with MTS showed better performance in general intellectual functioning, working memory, attentional span, and auditory-verbal learning compared to patients with non-MTS MRI lesions. Atrophy and focal cortical dysplasia had the largest differences from MTS.

Cognitive performance of refractory TLE patients varies concerning structural brain alterations. Further neuroimaging studies of TLE lead to prevention and more accurate management of cognitive decline in clinical settings.

Levetiracetam (LEV) is approved for treating epilepsy. The current evidence shows that LEV can cause behavioral problems such as depression. It is well-known that depression is associated with oxidative stress. Therefore, we conducted this study to assess the influence of LEV on depression severity and anti-oxidant status.

In this prospective longitudinal study, 50 patients with diagnosis of epilepsy on LEV were included. We used Beck Depression Inventory-II (BDI-II) to assess depression severity. The serum levels of zinc and glutathione were measured as anti-oxidant markers. These variables were evaluated at the baseline and 3 months after the commencement of LEV.

A total of 30 patients finished the follow-up. Among them, 21 patients were women. The mean age at baseline was 28.76 ± 11.37 (range: 16-68 years). The severity of depression at the last follow-up was significantly higher than the baseline. We observed a decrease in the serum levels of zinc and glutathione, though they were not statistically significant.

Our results suggest that LEV can increase the risk of depression in patients with epilepsy. This study also suggests that zinc depletion can be induced through act of LEV. Further studies are needed to validate these findings

Abnormalities in the structure of the cerebral cortex of patients with temporal lobe epilepsy can be detected by magnetic resonance imaging (MRI). However, many of these patients have a normal MRI even a few years after the disease. The aim of this study was to evaluate and compare the cortical thickness of patients with left and right temporal lobe epilepsy with healthy individuals using MRI images.

In the present study, MRI images of healthy control cases (n = 20) and patients with left temporal lobe epilepsy (n = 19) and right temporal lobe epilepsy (n = 14) were used. The mean cortical thickness of these patients was calculated using FREESURFER software. Finally, areas of the cerebral cortex affected by epilepsy were identified and introduced by Mann-Whitney U test.

Patients with left temporal lobe epilepsy had less cortical thickness than healthy individuals in the cingulate, anterior, occipital, and parietal lobes. Cortical thickness atrophy was seen in patients with right lobe epilepsy compared to healthy control individuals in the right hemisphere in the occipital lobe in the lateral occipital region. There was no significant difference between the mean cortical thickness in patients with right and left temporal lobe epilepsy.

In the present study, changes and disturbances in the thickness of gray matter in different areas of the cerebral cortex of patients with temporal lobe epilepsy have been identified as the effects of this disease on the cerebral cortex.

Frontal lobe epilepsy (FLE) is associated with cognitive dysfunction that may adversely affect the quality of life (QoL) before and after surgery for epilepsy. This study aimed to find cognitive factors that may predict QoL in patients with FLE whose seizures had been controlled by surgery for epilepsy.

Methods and Materials: 

Twenty-four patients with FLE who underwent epilepsy surgery from June 2014 to June 2019 were recruited. The seizure outcome was assessed with modified Engel classification. All of the patients were assessed by Wechsler Adult Intelligence Scale-Revised, Wechsler Memory Scale, Color Trails Test, Tower of London Test, Persian Aphasia Naming Test, and Persian Diagnostic Aphasia Battery. The QoL was evaluated with the QoL in Epilepsy Inventory with 89 items. Repeated measures analysis of variance and Generalized Linear Models (GLM) was used for statistical analysis.

The results showed that there was a significant difference between the scores of working memory (p = 0.01), general intelligence (p <0.001), and functional intelligence (p <0.001) before and after surgery. GLM regression model showed that color errors in part 2 of CTT by -18.43 and higher indexed scores of verbal memory by -1.28, both before surgery, predicted decreased total QOLIE score.

Working memory and executive functioning were neuropsychological factors that may predict QoL in after surgery for FLE.

about 20% to 30% of patients with epilepsy are diagnosed with drug-resistant epilepsy and one third of these are candidates for epilepsy surgery. Surgical resection of the epileptogenic tissue is a well-established method for treating patients with intractable focal epilepsy. Determining language laterality and locality is an important part of a comprehensive epilepsy program before surgery. Functional Magnetic Resonance Imaging (fMRI) has been increasingly employed as a non-invasive alternative method for the Wada test and cortical stimulation. Sensitive and accurate language tasks are essential for any reliable fMRI mapping. 

The present study reviews the methods of presurgical fMRI language mapping and their dedicated fMRI tasks, specifically for patients with epilepsy.

Different language tasks including verbal fluency are used in fMRI to determine language laterality and locality in different languages such as Persian. there are some considerations including the language materials and technical protocols for task design that all presurgical teams should take into consideration.

Accurate presurgical language mapping is very important to preserve patients language after surgery. This review was the first part of a project for designing standard tasks in Persian to help precise presurgical evaluation and in Iranian PWFIE.

The present study aimed to assess structural asymmetry in patients with mesial Temporal Lobe Epilepsy (mTLE) in the diffusion properties of brain white matter and subcortical gray matter tracts using Diffusion Tensor Imaging (DTI) and Diffusion Kurtosis Imaging (DKI). We considered a lower order DTI measure, Fractional Anisotropy (FA), and a higher-order DKI measure, Kurtosis Anisotropy (KA), as quantitative measures of the white matter diffusion properties in facing mTLE. We also made a comparison between these two measures in terms of the sensitivity to capture microstructural changes in concordance with TLE.

Thirty-two subjects with mTLE participated in this study. All the cases underwent multi-shell diffusion MRI acquisition. The subjects were grouped according to their epileptogenic side of the brain (19 Left-sided and 13 Right-sided TLE). Each group were analyzed separately using FSL package, then laterality analysis based on Tract-Based Spatial Statistics (TBSS) was performed on FA and KA images. After each analysis the left side of the patients’ brain was flipped and subtracted from the right side of the patients’s brain, and a voxel-wise z-score comparison was applied to find the significantly different areas. 

The results showed a considerable laterality effect on the temporal lobe white matters both in FA and KA, more emphasized in patients with Right-sided mTLE.

It can be concluded that these two measures, even though extracted from skeletonized images, can serve as decent biomarkers of laterality in case of mTLE, when the conventional MRI fails to capture the laterality.

Epilepsy is a chronic neurologic condition and affects people of all ages. Seizure clusters are generally referred to seizures that occur at close intervals with complete recovery between attacks. Various studies have reported a variety of frequencies and risk factors for this condition.

We designed a study to determine the frequency of seizure cluster and their associated risk factors in Iranian population for the first time.

Among 40 variables analyzed, 18 of them were significantly associated with seizure clustering. Risk factors including educational level, age of onset, number of drugs, seizure types, perinatal complication, developmental delay, other illnesses, parental consanguinity, systemic diseases, number of drugs used, mentation, motor signs, sensory signs, cranial nerves signs, cerebellar signs, seizure duration, existence of magnetic resonance imaging (MRI) lesion, and type of MRI pathology are significantly associated with clustering of seizures. When associated risk factors were analyzed with multivariate analysis, age of onset of seizures, number of antiepileptic drugs currently used, lack of seizure‑free periods, seizure frequency, and type of MRI pathology are significantly defining for anticipating clustering of seizures.

Seizure cluster has a significant negative impact on the quality of life of patients. Important risk factors that are found to be associated are age of onset, parental consanguinity, frequency of seizure, lack of have seizure‑free period or periods, pathologies in neurological examination, and MRI findings.

We conducted a study to evaluate the relationship between aura types and postoperative outcomes in patients with mesial temporal sclerosis (MTS) to predict the prognosis of patients, accordingly.

In this cross-sectional study, 99 patients with MTS-temporal lobe epilepsy were enrolled based on inclusion and exclusion criteria. The types of aura were evaluated, and the outcomes were categorized according to theEngel scale. Preoperative and postoperative results of patients were compared and analyzed with the Kruskal–Wallis test.

About 73.7% of patients had seizure-free after their surgeries. The most of patients (n = 81)were in Class I of Evaluating Engel criteria. About 36.3% had not experienced any aura before their seizures, and among those with aura, the most prevalent aura was abdominal aura in 29 patients (29.3%) followed by other types of aura and affective aura. Most of the patients in Class I, II, III, and IV of Engel scale had an abdominal aura, without aura, effective aura, and abdominal aura, respectively, but this difference was not statistically significant (P = 0.691).

According to this study, the type of aura cannot predict postoperative outcomes in MTS patients. More studies are needed to evaluate this relation in better-planned studies with greater sample size.

Interictal spikes not only are used to diagnose epilepsy, its syndromes, and therapeutic guidelines in patients with epilepsy, but also may be a window to understand anatomy, severity, and epilepsy outcomes better. The aim of this study was to investigate the relationship between interictal spike rate and magnetic resonance imaging (MRI) findings.

This descriptive cross-sectional study was performed on patients with refractory temporal lobe epilepsy admitted to epilepsy monitoring unit, Ayatollah Kashani hospital, Isfahan, Iran. Brain MRI (with epilepsy protocol) and all files related to long-term monitoring (LTM) of patients were studied, and then, the spike rate was calculated for each patient. Clinical information of patients as well as MRI and interictal findings were placed in separate tables designed for this purpose. Analysis of these findings consisted of two parts. In the first part, descriptive statistics (frequency and percentage), and for second part, inferential statistics (Spearman correlation coefficient and multivariate logistic regression) were used.

This study was done on 70 patients with refractory temporal lobe epilepsy, 44 men (62.9%) and 26 women (37.1%). The mean age of the participants was 29.00 ± 10.49 years (10-60). Spearman's correlation coefficient showed a significant relationship between spike rate and MRI findings (P < 0.050). The results of regression analysis showed that only two lesions of "Hippocampus and Amygdala sclerosis" and "tumor and tumor-like lesions" could predict spike rate among MRI lesions. Normal MRI could also predict the amount of spikes.

 It seems that a combination of brain MRI with physiological measurements, including interictal spike rate, can determine subtypes of refractory temporal lobe epilepsy, and can lead to better diagnosis and treatment.</div>

Since electroencephalography (EEG) signal contains temporal information and fMRI carries spatial information, we can reasonably expect that a combination of the two contributes greatly to precise localization of epileptic focuses. With that in mind, we have first extracted spike patterns from outside of scanner EEG, through detecting and averaging the interictal epileptiform discharges (IED). Then, having implemented the correlation between the identified pattern and inside-scanner EEG, an automated system was developed to extract the temporal information when an epileptic seizure is triggered. We proceeded to convolve the obtained regressor with the hemodynamic response function (HRF) using the general linear model (GLM) for the purpose of localizing the epileptic focus. This study was conducted on 6 medication-resistant patients with epilepsy whose data was recorded in the National Brain Mapping Lab (NBML). The results of the proposed method are in line with the information provided in EEG for each of the 6 patients, and for the 4 patients who were candidates for brain surgery, they provided further information. The results suggest a significant improvement in localization accuracy and precision compared to existing methods in the literature.

To investigate ictal onset patterns (IOP) in scalp electroencephalography (EEG) of patients with temporal lobe epilepsy (TLE) and their prognostic effect on the postoperative outcome.

We conducted a retrospective cohort study between 2011 and 2015 in our referral Epilepsy Surgery Center enrolling adult patients with refractory TLE and a visible epileptogenic lesion in magnetic resonance imaging (MRI), who underwent epilepsy surgery. Demographic, clinical and MRI findings were collected and ictal findings during video-EEG monitoring were reviewed in detail. The correlation between preoperative findings and the postsurgical outcome was analyzed.

We reviewed 303 seizures in 93 patients. Rhythmic theta and rhythmic spike/sharp and wave were respectively the most common initial ictal pattern and late significant discharges. Engel class I outcome was observed in 88.2% of patients. Female sex, aura, the absence of secondary generalization, rhythmic theta as initial ictal pattern and concordance of ictal-interictal EEG findings were correlated with favorable 1-year postsurgical outcome.

Preoperative clinical and EEG findings can provide valuable information regarding postsurgical prognosis in TLE patients.