Vagal Nerve Stimulation for Drug-Resistant Epilepsy: Adverse Events and Outcome in a Series of Patients with Long-Term Follow-Up.

BACKGROUND: Vagal nerve stimulation (VNS) is a palliative treatment option for drug-resistant epilepsy. The aim of this study was to describe the clinical and demographic features of selected patients scheduled for VNS and to evaluate the long-term efficacy of VNS in seizure control. MATERIALS AND METHODS: Between 2006 and 2013, 32 consecutive epileptic patients (14 male and 18 female) were enrolled at our Institute for VNS implantation. In all cases resective surgery had previously been excluded by the use of a noninvasive presurgical study protocol. Mean age was 32 years (range 18-50), and mean epilepsy duration 23 years (range 11-39). All subjects were followed-up for at least 2 years (mean 6 years, range 2-9) after VNS implantation. Patients were considered responders when a reduction of seizures of more than 50 % was reported. RESULTS: All patients had complex partial seizures, in 81 % of the patients with secondary generalization and in 56 % with drop attacks. Neurological examination revealed focal deficits in 19 % of the patients. Brain magnetic resonance imaging (MRI) was positive in 47 % of the patients. No surgical complications were observed in this series. Three patients were lost to follow-up. Twelve patients were classified as responders. Among the others, 1 patient experienced side effects (snoring and groaning during sleep) and the device was removed. CONCLUSIONS: Our data confirm that VNS is a safe procedure and a valid palliative treatment option for drug-resistant epileptic patients not suitable for resective surgery.

A case of epilepsia partialis continua of abdominal muscles after brain tumor surgery.

Epilepsia partialis continua (EPC) is a rare form of focal motor status epilepticus characterized by continuous muscular twitches or jerks involving a limited part of the body, usually facial region and distal limb. Although the cerebrovascular disease is known to be one of the most common causes of this condition, other reported cases with predominant abdominal involvement have different aetiologies, including, tumors, focal cortical dysplasia, and central nervous system infections. No cases of epilepsia partialis continua of the abdominal wall occurred after brain surgery have been previously reported. We describe the clinical, electrophysiological, and neuroimaging findings in an adult patient presenting with persistent unilateral abdominal myoclonus configuring an EPC as the evolution of a super-refractory hemibody convulsive status epilepticus, occurred after brain tumor surgery.

Changes in depression, anxiety, anger, and personality after resective surgery for drug-resistant temporal lobe epilepsy: a 2-year follow-up study.

OBJECTIVE: To further elucidate the psychiatric outcome of surgical treatment for temporal lobe epilepsy (TLE). METHODS: Fifty-two consecutive patients with drug-resistant TLE and IQ > or = 70 completed the Minnesota Multiphasic Personality Inventory, Beck Depression Inventory, Spielberger State-Trait Anxiety Inventory, and Spielberger State-Trait Anger Expression Inventory before epilepsy surgery, after 1 year, and after 2 years. Some patients also completed the 31-item Quality of Life in Epilepsy (N=29) and WHOQOL-100 (N=24) questionnaires. During the follow-up period, patients were maintained on a stable medication regimen. Multivariate repeated measures analysis of variance was used to examine changes in psychiatric variables over time. RESULTS: Seizure outcome was excellent (89% in Engel class I after 2 years). There were only a few significant changes over time in the MMPI profile, suggesting a decrease in interpersonal sensitivity, irritability, and social introversion. Anxiety decreased significantly with a gradual decline, anger dropped significantly after remaining basically flat during the first year, while depression showed a gradual but non-significant decline. Younger age and shorter duration of epilepsy were associated with greater improvement in several anger dimensions. In the patient subgroup with quality of life data available, greater improvement in overall quality of life and key life domains (income, work capacity, personal relationships) was found to be associated with greater decrease in depression, anxiety, and anger. CONCLUSION: The relatively slow decrease of emotional distress over time and its correlation with changes in some key life domains suggest that patients may experience difficulties in switching from a 'sick' role to a 'normal' role, and may easily be disappointed if expectations of positive life changes are not rapidly met. Some counselling sessions early after surgery may be useful to address these issues. The findings also suggest that surgery may yield greater emotional benefits if performed early.

Interhemispheric transfer time in a patient with a partial lesion of the corpus callosum.

The interhemispheric transfer time (ITT) of basic visuo-motor integration was investigated in a patient who had a lesion of the corpus callosum that spared the splenium and rostrum. Overall, 4291 simple reaction times were collected during unimanual responses to tachistoscopically presented lateralized simple visual stimuli at 4 degrees, 6 degrees and 10 degrees. Despite retaining some abilities that typically require the integration of information between hemispheres (e.g. haptic naming, tachistoscopic lateralized consonant reading) the patient performed similarly to completely callosotomized patients in a basic visuo-motor ITT task (overall 25.5 ms) at any eccentricity. These findings suggest that specific callosal channels mediate the basic visuo-motor ITT and these do not include the rostrum and/or the splenium of the corpus callosum.

Severe amnesia following bilateral medial temporal lobe damage occurring on two distinct occasions.

A comprehensive neuropsychological assessment was performed on a 38-year-old woman with drug-resistant right temporal lobe epilepsy before temporal lobectomy, during a 2-year follow-up period, and approximately 3 years after surgery when she developed a malignant glioma in the left medial temporal lobe (MTL). Both before and after epilepsy surgery, memory function was normal. When the tumour was discovered, the patient suffered from severe retrograde and anterograde amnesia, whereas working memory and the other cognitive abilities were preserved. Compared with other cases of bilateral temporal lesion, this case is peculiar because the damage occurred on two distinct occasions. It suggests that only one MTL can allow normal memory function, or can take over the function normally subserved by a dysfunctional contralateral MTL when the dysfunction is marked and prolonged, such as in chronic epilepsy.

Lateralizing value of memory tests in drug-resistant temporal lobe epilepsy.

Our aim was to test the lateralizing value of a neuropsychological battery including several memory tests on a large sample of consecutive patients with drug-resistant temporal lobe epilepsy (TLE) evaluated for epilepsy surgery. We studied 73 right-handed patients (56% males, mean age 35.3 +/- 11.2 years, 49% left TLE) aged 16 years or older with normal IQ who underwent a preoperative neuropsychological assessment including several memory tests and were seizure-free after at least 1 year of follow-up. Forty-seven had TLE due to hippocampal sclerosis, whilst 26 had TLE secondary to tumors or other lesions. Receiver Operating Characteristic (ROC) analysis and discriminant function analysis were used to evaluate the lateralization value of selected tests and of the battery as a whole, respectively. In patients with TLE secondary to tumors or other lesions, no test showed significant lateralizing value. In patients with TLE due to hippocampal sclerosis, the immediate (P < 0.01) and delayed (P < 0.001) Rey Auditory Verbal Learning Test (RAVLT) displayed substantial discriminatory ability. The battery as a whole correctly classified 82% of patients with respect to side of epileptogenesis. Our findings suggest that a non-invasive, relatively short and unexpensive neuropsychological battery based on memory tests may profitably complement other well-established diagnostic procedures such as video-EEG or magnetic resonance imaging (MRI), at least in patients with drug-resistant TLE due to hippocampal sclerosis.

Temporal lobe epilepsy surgery: different surgical strategies after a non-invasive diagnostic protocol.

AIM: To test a non-invasive presurgical protocol for temporal lobe epilepsy (TLE) based on "anatomo-electro-clinical correlations". METHODS: All consecutive patients with suspected TLE and seizure history <2 years were entered into the protocol, which included video-electroencephalographic (EEG) monitoring and magnetic resonance imaging (MRI). Three different TLE subsyndromes (mesial, lateral, mesiolateral) were identified by combined anatomical, electrical, and clinical criteria. "Tailored" surgery for each subsyndrome was offered. Patients with seizure history <2 years, MRI evidence of temporal mass lesion, and concordant interictal EEG and clinical data bypassed video-EEG monitoring and were directly scheduled for surgery. RESULTS: Lesionectomy was performed without video-EEG recording in 11 patients with tumorous TLE. Of 146 patients studied with video-EEG, 133 received a TLE diagnosis. Four were excluded for neuropsychological risks, eight refused surgery, and 121 underwent surgery. Of 132 consecutive patients who underwent surgery, 101 had at least one year of follow up. They were divided into a "hippocampal sclerosis/cryptogenic" group (n = 57) and a "tumours/cortical organisation disorders" group (n = 44). In the first group, extensive temporal lobectomy (ETL) was performed in 40 patients, anteromesial temporal lobectomy (AMTL) in 17 patients. At follow up, 47 patients were seizure free. In the second group, lesionectomy plus ETL was performed in 23 patients, lesionectomy plus AMTL in six patients, and lesionectomy alone in 15 patients. Thirty nine patients were seizure free. CONCLUSIONS: These findings suggest that different TLE subsyndromes can be identified accurately using non-invasive anatomo-electro-clinical data and can be treated effectively and safely with tailored surgery.

Cerebellar contribution to spatial event processing: right/left discrimination abilities in rats.

Recently, we demonstrated the involvement of cerebellar circuits in the procedural components of spatial information processing by testing hemicerebellectomized (HCbed) rats in classical spatial paradigms, such as the Morris Water Maze and the water T-maze. Since procedural components are strongly present in these tests, an impairment also in processing more abstract spatial information, linked to 'where an object is' rather than to 'how to find it', could be hidden by the severe procedural deficits. On this basis, we investigated the influence of cerebellar lesions on spatial abilities strictly reducing procedural variables by employing an active avoidance task, first without and then with a request for right/left discrimination. In the two-way active avoidance task without spatial requests, controls and cerebellar operated rats developed active avoidance responses which were not statistically different, demonstrating that this kind of associative learning is not significantly affected by hemicerebellectomy (HCb). A second experimental group of cerebellar lesioned rats was tested in a modified version of this basic paradigm in which a right/left discrimination request was added. This group displayed severe deficits, which even in the last testing sessions prevented them from performing comparably to the control animals. Reversal of the rewarded choice, even if it affected the performances of both controls and operated rats in the first inversion trials, elicited the lowest number of correct responses in HCbed rats throughout the entire spatial reversal learning, suggesting a severe deficit in the ability to change an initially learned behaviour. These results demonstrate that, beside having a marked impairment in facing procedural components of spatial processing, cerebellar lesioned rats are severely defective also in right/left discrimination tasks, suggesting a role of cerebellar networks also in the discriminative spatial information processing.

Spatial event processing.

The present review advances experimental evidence on the cerebellar involvement in spatial data processing. In particular, data on Morris water maze (MWM) performances of hemicerebellectomized (HCbed) rats indicate a specific cerebellar role within the procedural aspects of spatial functions. In MWM testing, HCbed animals are impaired in developing efficient exploration strategies and display only old and rather ineffective ways for acquiring spatial information, such as peripheral circling around the pool. This behavior is not exhibited if spatial mapping abilities are preoperatively acquired. Thus, MWM experimental data point toward a procedural deficit that specifically impairs the acquisition phase. The characteristics of the cerebellar involvement in affecting the procedures needed for spatial data management are discussed in the light of recent theories on spatial data processing and on cerebellar timing and ordering functions.