Do Spike Domain Analysis Interictally Correlate With the Ictal Patterns in Temporal Lobe Epilepsy?

PURPOSE: To study if one can conceptualize the scalp ictal onset pattern through analysis of interictal spike domain analysis in temporal lobe epilepsy (TLE). METHODS: Seventy-four patients with unilateral mesial temporal sclerosis (MTS) were categorized into "type A" interictal epileptiform discharges (IEDs) with negativity over infero-lateral scalp electrodes over temporal region and contralateral central region showing positivity; all IEDs other than type A were categorized as type B. The ictal electrographic patterns was termed "focal" when confined to side of MTS, was "regional" when lateralized to the ipsilateral hemisphere; "diffuse" if nonlateralized/localized; and ictal onset contralateral to MTS termed as "discordant." RESULTS: A total of 377 seizures and 5,476 spikes were studied. These were divided into four types: (1) type A IEDs ipsilateral to MTS (44 patients), (2) type A IEDs bitemporally (16 patients), (3) type A IEDs contralaterally (7 patients) and type B IEDs ipsilaterally, and (4) bilateral type B IEDs (7 patients). The ictal pattern was either focal or regional in 51 of 60 patients (85%) with type A IEDs; it was "diffuse" in 9 patients (15%). Diffuse ictal onset was seen in 12 of 14 (86%) with either ipsilateral/bitemporal type B IEDs. Ictal onset on the opposite hemisphere was noted in 2 (14%). CONCLUSIONS: Type A IEDs signify a focal ictal onset and type B IEDs suggest a diffuse ictal onset in patients with MTS on one side. SIGNIFICANCE: Interictal spike domain analysis helps predicting ictal patterns in temporal lobe epilepsy.

How does "locus of control" affect persons with epilepsy?

PURPOSE: Locus of control (LOC) is the degree to which people believe that they have control over the outcome of events in their lives. A person's locus can be internal, external, or chance. A person with internal locus of control believes that one can control one's own life. A person with external locus of control believes that his life is controlled by external factors or people over which he has no influence. A person with chance locus of control believes that fate, chance, or luck controls his own life. The aim of the current study was to determine the health locus of control, anxiety, and depression levels in persons with epilepsy (PWE) and to assess whether locus of control has relation to anxiety, depression, and seizure control. METHODS: Patients aged 18 years or older with a history of epilepsy for at least 1 year were recruited from the outpatient epilepsy clinic or from the inpatient epilepsy monitoring unit at SCTIMST, Trivandrum from January 2019 to May 2020. Patients filled the questionnaire form consisting of demographic data, age of onset of seizures, present seizure control, and the current antiepileptic drugs. The Hospital Anxiety and Depression (HAD) scale was used to estimate the level of anxiety and depression in these patients. The Form-C of the Multidimensional Health Locus of Control (MHLC) scale was used to evaluate the health locus of control. Healthy controls aged 18 years or older and free of any chronic disease or psychiatric illness were also recruited. They were asked to fill the questionnaire forms with basic demographic data. HAD scale was used to estimate the level of anxiety and depression and form-C of MHLC was used to evaluate the health locus of control in the healthy controls. The mean scores of anxiety, depression, and locus of control were compared between the two groups. RESULTS: A total of 170 participants were recruited which consisted of 100 PWE and 70 healthy controls. The mean anxiety and depression scores were 8.13(SD = 4.23) and 5.85(SD = 3.66) in the PWE group and 6.75(SD = 3.39) and 4.14(SD = 2.96) in the control group, respectively. The mean internal, external, and chance LOC scores were 24.95(SD = 10.92), 26.94(SD = 4.96), and 24.41(SD = 6.46) in the PWE group; and 29.44(SD = 5.62), 26.53(SD = 5.79), and 19.9(SD = 7.13) in the control group, respectively. Persons with epilepsy had higher chance LOC scores and lower internal LOC scores compared to controls (p = 0.00003, p < 0.00001 respectively). There were no differences in the external LOC scores between the two groups (p = 0.620). Persons with epilepsy with some level of anxiety had lower internal LOC scores compared to patients with no anxiety (p = 0.04). PWE with poor seizure control had higher external LOC score and lower internal LOC scores which however did not reach statistical significance. Persons with epilepsy with poor seizure control had higher anxiety and depression scores. CONCLUSIONS: Persons with epilepsy had low perceptions of internal and strong perceptions of chance health locus of control. This means that PWE feel that luck plays an important role in their disease control. This information is important in the counseling of persons with epilepsy.

Personality disorders in temporal lobe epilepsy: What do they signify?

OBJECTIVES: To estimate the prevalence of personality disorders in patients with temporal lobe epilepsy (TLE) with mesial temporal sclerosis (MTS) and compare it with general population and analyze their implications on treatment outcome. MATERIALS AND METHODS: TLE was diagnosed based on clinical history, MRI, and Video EEG data. IPDE-ICD10 screening questionnaire was applied to investigate personality disorder in 120 subjects, 60 cases, and 60 normal controls. Bear-Fedio inventory (BFI) was used to study different behavior traits in patients with TLE and controls. RESULTS: Prevalence of personality disorders was higher (71.7% in cases versus 38.3% in controls) in patients with TLE compared to controls (P < .001). Some personality traits like schizoid (P = .002), dissocial (P = .001), impulsive (P = .003), anankastic (P < .001), anxious (P < .001), and dependent (P < .001) personalities were found to have high prevalence in TLE. Personality disorder was higher among those cases who had been tried on more than two antiepileptic drugs (AEDs) (P = .033) and in those with duration of illness more than 10 years (P = .026). Cases also showed significantly higher score in BFI for all behavioral traits except for aggression. No significant difference of BFI score was seen based on laterality of epileptic focus, gender, duration of illness, or number of AEDs tried. CONCLUSION: There is a significantly higher prevalence of personality disorders in patients with TLE. Specific interventions for these disorders should be considered at the earliest pari passu with AEDs and surgery.

Self-regulation of language areas using real-time functional MRI in stroke patients with expressive aphasia.

The objectives of this study were to test (i) If stroke patients with expressive Aphasia could learn to up-regulate the Blood Oxygenation Level Dependent (BOLD) signal in language areas of the brain, namely Inferior Frontal Gyrus (Broca's area) and Superior Temporal Gyrus (Wernicke's area), with real-time fMRI based neurofeedback of the BOLD activation and functional connectivity between the language areas; and (ii) acquired up-regulation could lead to an improvement in expression of language. The study was performed on three groups: Group 1 (n = 4) of Test patients and group 2 (n = 4) of healthy volunteers underwent the neurofeedback training, whereas group 3 (n = 4) of Control patients underwent treatment as usual. Language performance and recovery were assessed using western aphasia battery and picture naming tasks, before and after the neurofeedback training. Results show that the Test group had significant increase in activation of the Broca's area and its right homologue, while the Normal group achieved the greatest activation during neurofeedback. For the Test group both perilesional and contralateral activations were observed. The improvement in language ability of the test patients was not significantly greater than that of the control patients. Neurofeedback training in Aphasia patients induced significant activation of the Broca's area, Wernicke's area and their right homologues, although healthy individuals achieved greater activations in these regions than the patient groups. Training also activated perilesional areas of Rolandic operculum, precentral gyrus and postcentral gyrus for the Test patients significantly. However, lack of behavioral and symptom modifications in the Test group calls for improvements in the efficacy of the approach.

How safe is bone health in patients on newer or enzyme inhibitor antiepileptic drugs?

BACKGROUND: Data on the effect of enzyme inhibitors and newer anti-epileptic drugs (AEDs) on bone health is limited with conflicting results. AIM: We compared the effects on bone health of patients exposed to enzyme inducer versus enzyme inhibitor AEDs and newer versus older AEDs. METHODS: We prospectively studied 51 patients on AEDs for more than two years and equal age and sex matched controls from March 2017 to September 2018. Biochemical bone mineral markers and bone mineral density (BMD) were measured and analysed between patients versus controls and between various sub-groups based on enzymatic effect, generation and number of AEDs. RESULTS: Of 51 patients,11(21.5%) had osteopenia and 3(5.9%) had osteoporosis. T-score (-0.75 ±â€¯1.22 versus 0.004 ±â€¯1.0, p < .001) and Z-score at femur neck (-0.38 ±â€¯1.08 versus0.002 ±â€¯0.81, p < .001) were found to be significantly lower in patients compared to controls. Relative risk for low BMD was higher in patients on polytherapy compared to monotherapy (RR = 1.37,CI = 0.69-2.74).Higher relative risk for low BMD was noted with; clobazam (RR = 1.51,CI = 0.82-2.78), oxcarbazepine (RR = 1.33,CI = 0.68-2.59), phenobarbitone (RR = 1.31,CI = 0.26-6.7) and leviteracetam (RR = 1.18,CI = 0.45-3.06) mono or polytherapy and valproate monotherapy (RR = 3.5,CI = 1.09-11.29). No significant difference was noted with regards to mean dosage or metabolic or radiological markers of bone health between patients on enzyme inducer versus inhibitors and newer versus older AEDs. A significant negative correlation was found between cumulative drug load and femur T-score (r2 = -0.27, p = .04). CONCLUSION: Bone health in epilepsy is adversely affected by chronic exposure to AEDs; irrespective of the enzymatic effect or generation of AEDs. Complex pharmacodynamic mechanisms of AEDs as well as pharmacokinetic interactions between various AED polytherapies affects bone health.

Seizure outcome and its predictors after frontal lobe epilepsy surgery.

OBJECTIVES: Frontal lobe epilepsy (FLE) surgery is the second most common focal resective surgery for drug-resistant epilepsy. Not many studies are available regarding the long-term surgical outcome of FLE. We studied the longitudinal outcome and predictors of seizure outcome following FLE surgery in a sizeable cohort of patients. MATERIALS & METHODS: A total of 73 consecutive patients who underwent FLE surgery between January 1997 and May 2015 with a minimum follow-up of 1 year (range 1-16 years) were studied. Primary outcome was seizure freedom at last follow-up (Engel Class IA). "Seizure freedom" separately was defined as absence of seizures till last follow-up. Outcome predictors were subjected to multivariate analysis. Using Kaplan-Meier curve, we assessed the post-operative seizure freedom over time. RESULTS: Twenty-five patients (34%) were seizure-free till last follow-up. The seizure freedom was 45%, 34%, 26%, 20% and 14% at the end of 1st, 2nd, 3rd, 4th and 5th post-operative year, respectively. Engel class I outcomes were 48%, 41%, 56%, 57% and 53% at end of 1st, 2nd, 3rd, 4th and 5th post-operative year, respectively. Predictors of seizure recurrence on multivariate analysis were older age at surgery (P = 0.032), longer duration of epilepsy (P = 0.031), presence of interictal epileptiform discharges in post-operative EEG on 7th day (P = 0.005), 3 months (P = 0.005) and 1 year (P = 0.0179). In subgroup analysis, duration of epilepsy of less than 2 years before surgery was a significant predictor for achieving seizure freedom (P = 0.029). CONCLUSIONS: These results emphasize early surgery for better outcome in frontal lobe epilepsy. Post-operative EEG remained a good predictor for long-term outcome.

Do auras predict seizure outcome after temporal lobe epilepsy surgery?

PURPOSE: The success of epilepsy surgery lies in identifying the ictal onset zone accurately. The significance of auras has little been explored on surgical outcome in drug-resistant epilepsy. This study focuses on the clinicopathological correlation of aura(s) and its role in predicting surgical outcome in drug-resistant temporal lobe epilepsy (TLE). We compared surgical outcome in TLE between patients with and without aura and identified the clinico-pathological, radiological and surgical differences between the two groups. METHODS: Consecutive patients who underwent presurgical evaluation from January 2009 to December 2014 for drug-resistant TLE who underwent anterior temporal lobectomy (ATL) were included. Patients were followed up at 3months, 12 months and then annually. RESULTS: Among 456 patients, 344(75%) had aura. Multivariate logistic regression showed that prototype EEG pattern at ictal onset (OR 2.12, 95% CI 1.18-3.06, p = 0.012) and right sided epileptogenic zone (OR 1.82 95% CI 1.18-3.78, p = 0.007) were significantly associated with presence of aura. There was no difference in surgical outcome between those with and without aura. But patients with auditory aura (OR 7.28, CI 2.80-18.95, p = 0.0002) and vertiginous aura (OR 3.01, CI 1.55-7.85, p = 0.028) had a poor surgical outcome. Bivariate analysis showed that normal MRI (p = 0.028) and normal/indeterminate pathology (p = 0.001) were significantly more common with auditory/vertiginous auras. CONCLUSIONS: Mere presence of aura does not affect outcome after TLE surgery. However, auditory and vertiginous auras are predictors of poor surgical outcome. These patients require more extensive screening for an ictal onset zone beyond standard limits of ATL before surgery.

Quantitative analysis of grey matter degeneration in FTD patients using fractal dimension analysis.

Fractal dimension (FD) is a quantitative parameter that can characterizes the complexity of human brain tissue. Extensive grey matter (GM) pathology has been previously identified in Frontotemporal dementia (FTD) and its variants. The aim of the present study was to investigate the GM morphometric abnormalities in the behavioral variant FTD (bvFTD) and primary progressive aphasia (PPA) using FD analysis. Twenty-seven bvFTD, 12 PPA and 20 controls were studied. SPM8 was used to segment the brain into GM tissue. Then the FD values were estimated for the GM skeleton, surface and general structure in patients and controls using our previously published algorithm. We found that patients with bvFTD had significant reduction in FD values of skeleton and general structure when compared to controls. In PPA, more significant decrease in FD was noted in the whole brain and left hemisphere skeleton along with left hemisphere general structure. Only the right hemisphere skeleton had a significant correlation with total score of Frontal Systems Behavior Scale (FrSBe). The results showed that the variants of FTD are associated with disease specific morphometric complexity patterns. These results indicate that FD can be used as a biomarker for the structural changes associated with neurodegenerative diseases.

fMRI paradigm designing and post-processing tools.

In this article, we first review some aspects of functional magnetic resonance imaging (fMRI) paradigm designing for major cognitive functions by using stimulus delivery systems like Cogent, E-Prime, Presentation, etc., along with their technical aspects. We also review the stimulus presentation possibilities (block, event-related) for visual or auditory paradigms and their advantage in both clinical and research setting. The second part mainly focus on various fMRI data post-processing tools such as Statistical Parametric Mapping (SPM) and Brain Voyager, and discuss the particulars of various preprocessing steps involved (realignment, co-registration, normalization, smoothing) in these software and also the statistical analysis principles of General Linear Modeling for final interpretation of a functional activation result.