Youssef G. Comair

Neuropsychological Effect of Temporal Lobe Resection in Preadolescent Children with Epilepsy

Summary: Purpose: Numerous studies have demonstrated changes in cognitive, memory, and language functioning in adults and adolescents after temporal lobectomy, yet little information is available regarding neuropsychological outcome in preadolescent children.

Surgical management of pediatric tumor-associated epilepsy.

Brain tumors are a common cause of seizures in children. Early surgical treatment can improve seizure outcome, but controversy exists regarding the most appropriate type of surgical intervention. Some studies suggest tumor resection alone is sufficient, while others recommend mapping and resection of the surrounding epileptogenic foci to optimize seizure outcome. To address this issue, we reviewed the charts of 34 pediatric patients aged 18 months to 20 years with medically intractable epilepsy and primary brain tumors. The average age at operation was 12.6 years, and patients had seizures for an average of 6.4 years. The majority of tumors were located in the temporal lobe. Seventeen patients, because of tumor location near an eloquent area, underwent extraoperative mapping using subdural electrode grids prior to definitive tumor resection. Fourteen of these patients had a gross total tumor resection, yet only two had a distinct zone of ictal onset identified and resected. The remaining 17 patients had tumors either in the nondominant hemisphere or far removed from speech-sensitive areas, and therefore did not undergo extraoperative subdural electroencephalograph mapping. Fourteen of these patients also had a gross total tumor resection, while none had intraoperative electrocorticography to guide the resection of additional nontumoral tissue. Overall, of the 28 patients treated with a gross total tumor resection, 24 (86%) are seizure free, while the other four are significantly improved. Of the six patients who had a subtotal tumor removal, five have persistent seizures. The mean follow-up was 3.6 years. We conclude that in children and adolescents, completeness of tumor resection is the most important factor in determining seizure outcome. The routine mapping and resection of epileptogenic foci might not be necessary in the majority of patients. As a corollary, the use of subdural electrode grids in pediatric patients with tumor-associated epilepsy should be limited to cases requiring extraoperative cortical stimulation for localization of nearby eloquent cortex. (J Child Neurol 1999;14:15-25).

Deep brain stimulation as a mode of treatment of early onset pantothenate kinase-associated neurodegeneration

We report a case of a young girl with early onset pantothenate kinase-kssociated neurodegeneration (PKAN) whose initial clinical manifestation was ataxia at the age of 2.5 years. Subsequently the patient presented to us with refractory severe dystonia resulting in essentially complete loss of motor control. She had a mutation in PANK2 gene consisting of an aminoacid change of Alanine to Valine in exon 5 (A382V). After Globus Pallidus deep brain stimulation (DBS) at the age of 11 years, the patient regained useful motor function and speech with a marked decrease in the severity of the dystonia. The patients condition gradually returned to her pre-DBS status when the device had to be removed 3 months later due to infection. Our case is the sixth case with classical PKAN that was treated by Globus Pallidus stimulation, the fifth one to have a favorable response to it and the only one in whom response was proven by the inadvertent removal of the DBS device due to infection. In addition, our case had a novel mutation and novel clinical features (onset with ataxia, occurrence of early seizure activity) on top of her other symptoms that were otherwise typical of early onset disease.

Sub-Second Dopamine Detection in Human Striatum

Fast-scan cyclic voltammetry at carbon fiber microelectrodes allows rapid (sub-second) measurements of dopamine release in behaving animals. Herein, we report the modification of existing technology and demonstrate the feasibility of making sub-second measurements of dopamine release in the caudate nucleus of a human subject during brain surgery. First, we describe the modification of our electrodes that allow for measurements to be made in a human brain. Next, we demonstrate in vitro and in vivo, that our modified electrodes can measure stimulated dopamine release in a rat brain equivalently to previously determined rodent electrodes. Finally, we demonstrate acute measurements of dopamine release in the caudate of a human patient during DBS electrode implantation surgery. The data generated are highly amenable for future work investigating the relationship between dopamine levels and important decision variables in human decision-making tasks.

Epilepsy surgery in children with pervasive developmental disorder

Pervasive developmental disorder (PDD) is occasionally associated with medically intractable complex partial seizures. The outcome of PDD was explored in three males and two females who underwent epilepsy surgery at 32 months to 8 years of age (mean = 4 years) after onset of epilepsy at 1 week to 21 months of age (mean = 11 months). Four children had temporal lobe resections (three right, one left; two for focal cortical dysplasia, and two for tumors), and one had a right temporoparieto-occipital resection (for focal cortical dysplasia). Each child underwent repeated evaluations by a pediatric neuropsychologist and psychiatrist. Fourteen to 47 months (mean = 23 months) after operation, one child with persistent seizures had moderate developmental and behavioral improvement, three children (two seizure free, one with rare staring spells) had mild developmental and behavioral improvement, and the remaining child (seizure free) experienced a worsening of her PDD. The four children with mild-to-moderate improvement in postoperative cognitive and behavioral development still demonstrated persistent delay. Cognitive gains were confirmed by neuropsychologic testing in the oldest patient but were not reflected in test results from the three younger children, who had more modest improvement. The child with worsening of her PDD had cognitive and emotional deterioration to babbling, echolalia, aggressiveness, decreased social interaction, and increased mouthing of objects beginning several months postoperatively. These results suggest that families should be counseled that PDD symptoms in children with focal epileptogenic lesions may or may not improve after epilepsy surgery, even if the surgery is successful with respect to seizure control.

Normalization of Quality of Life Three Years after Temporal Lobectomy: A Controlled Study

Summary:u2002 Purpose: The goal of epilepsy surgery is not merely to control previously intractable seizures, but also to improve quality of life (QOL). Our goals were to assess, in our Middle Eastern population, the QOL of adults with temporal lobe epilepsy (TLE) 3 years after temporal lobectomy as compared with matched TLE patients who did not undergo surgery and with healthy individuals in the same community.

Quality of life after surgery for intractable partial epilepsy in children: A cohort study with controls

PURPOSEnInvestigate if quality of life (QOL) normalizes on long-term follow-up after surgery for partial epilepsy in children.nnnMETHODSnThis is a cohort study with controls in which a consecutive cohort of nineteen 2-14-year-old children who underwent focal resections for intractable partial seizures between 1996 and 2006, were matched with 19 non-surgery intractable partial epilepsy patients, and with 19 healthy subjects. The two epilepsy groups were matched for age, sex, socio-economic status (SES), cognitive level, seizure type, and seizure frequency. The healthy group was matched with the two epilepsy groups for age, sex, SES, and cognitive level. QOL was assessed using the QOLCE (Quality of Life in Childhood Epilepsy Questionnaire).nnnRESULTSnIn the surgery group (follow-up 3.84+/-2.26 years), 78.9% had Engel class-I versus 21.1% in non-surgery (p=0.01) (follow-up 3.44+/-2.95 years). Surgery patients were similar to healthy subjects in the social, emotional, cognitive, behavioral, and overall QOL (p>0.05) but had lower scores in the total QOL, physical, and health domains (p<0.05). Surgery patients scored better than non-surgery in the behavioral domain and the HASES (Hague Side Effects Scale) score (p<0.05). Non-surgery patients scored worse than healthy in total QOL, physical, behavioral, health, and overall QOL (p<0.05). IQ, HASS (Hague Seizure Severity Scale), and HASES scores were positively associated with total QOL score (p<0.05). Subgroup analysis on seizure-free surgery patients showed that they did not differ from healthy subjects in any of QOL domains (p>0.05, power>0.8).nnnCONCLUSIONnOur data indicate that epilepsy surgery for partial seizures in children is associated with better QOL as compared to children with intractable epilepsy who are not operated on, and suggest that in those who achieve seizure freedom normal QOL may at least potentially be possible.

Marked benefits in physical activity and well-being, but not in functioning domains, 2 years after successful epilepsy surgery in children.

In this first study comparing epilepsy-specific quality-of-life measures of children after epilepsy surgery (2.4 years after focal resection) with those of a matched comparison group of nonoperated patients, seizure severity, medication side effects, overall quality of life, general health, physical activity, and well-being were better in surgical patients (70.6% seizure free vs 8.3%). Cognitive, social, and behavioral functioning did not differ, suggesting that these may require additional interventions during postsurgical follow-up.

Effects of epilepsy surgery on quality of life: a controlled study in a Middle Eastern population

The purpose of this study was to investigate which areas of quality of life (QOL) change after epilepsy surgery and generate QOL data specific to the Lebanese population. The QOL of 20 consecutive patients 1 year after surgery was compared (using the ESI-55 scale) with that of 20 matched patients who underwent the same presurgical evaluation, but no surgery. Overall QOL improved in both groups, but was greater in the surgery group (85% seizure free as compared to 0% in nonsurgery group). Significant differences were noted within the well-being domain including health perception (5/9 items), energy-fatigue (2/4), and emotional well-being (2/5). Differences were less common in the functioning domain including physical (1/10 items), social (1/2), and cognitive (0/5) functioning scales, and in the role limitation domain (1/17 items). Our patients experienced, 1 year after epilepsy surgery, improvements similar to those reported in Western populations after a similar period: they had marked improvements in overall QOL, health perception, well-being, and cognitive functioning areas. They had less remarkable improvements in social functioning and role limitation areas.

Quality of life after vagal nerve stimulator insertion

AIMnAssess quality-of-life after vagal nerve stimulation and determine patient characteristics associated with improvement in quality-of-life.nnnMETHODSnSixteen patients (11 children, 5 adults) who had vagal nerve stimulation at our center were studied. Quality-of-life was assessed pre- and post-vagal nerve stimulation using the Quality-of-Life in Childhood Epilepsy questionnaire for children and the Epilepsy Surgery Inventory-55 for adults.nnnRESULTSnSixteen patients who did not qualify for resective surgery were included; seven (43.75%) were males and 9 (56.25%) were females. Mean age at onset of seizures was 3.96 +/- 4.00 years and at surgery was 15.78 +/- 10.78. Follow-up time was 1.26 +/- 0.92 years. Fourteen patients (87.5%) were mentally retarded. Ten (62.5%) had cryptogenic etiology and 6 patients (37.5%) symptomatic etiology. Fifty percent had localization-related epilepsy. Six of 7 patients with generalized cryptogenic etiology (85.71%) had Lennox-Gastaut syndrome. Seizures dropped from 122.31 +/- 159.49 to 67.84 +/- 88.22 seizures/month. Seizure reduction (> 50%) correlated with improvement in total quality-of-life (p = 0.034). Post-vagal nerve stimulation, the total group scored significantly higher in the social domain (p = 0.039). In patients with localization-related epilepsy, significant improvements were detected in the social domain (p = 0.049) and in total quality-of-life (p = 0.042).nnnCONCLUSIONnDespite a diverse and small population size, we observed significant improvements in the social domain 1.26 years post-vagal nerve stimulation. In addition, there was an improvement in total quality-of-life amongst patients with partial seizures. Finally, seizure reduction was associated with quality-of-life improvement. Our results support previous studies from the West reporting improvement in quality-of-life following vagal nerve stimulation, contradict those studies that did not show such differences, and are the first coming from a developing country.