Cognitive outcome of pediatric epilepsy surgery across ages and different types of surgeries: A monocentric 1-year follow-up study in 306 patients of school age.

OBJECTIVE: The neuropsychological outcome of pediatric epilepsy surgery has been reported before, but only few studies compared different major types of surgery in differentially located epilepsies. METHODS: Neuropsychological performance of 306 children and adolescents (ages 6-17 years) were assessed before and one year after epilepsy surgery. Individual impairments, changes into and out of impairment, as well as intraindividually meaningful positive or negative changes were examined. Regression analyses addressed the effects of site, side, pathology, type of surgery, seizure outcome, and drug change on the cognitive and behavioral domains. RESULTS: Preoperatively 85% of the patients had cognitive impairments in at least one domain, 71% had behavioral problems. Postoperatively the number of impaired patients dropped considerably: 21-50% of the patients changed from impaired to unimpaired, individually significant gains were registered in 16-42%. Seizure freedom was achieved in 81% of all patients. The number of antiepileptic drugs decreased significantly. Seizure freedom, a younger age at evaluation, a later age at onset, a lower antiepileptic drug load, and less baseline damage predict better cognitive and behavioral outcomes. Gender, pathology, localization, and lateralization had little or no impact. CONCLUSION: Differentially located and lateralized epilepsies hardly differed in cognition and behavior indicating nonspecific developmental rather than domain specific impairments. Childhood epilepsy surgery is very successful and the functional improvements one year after surgery confirm the general relevance of baseline damage, mental reserve capacities, functional plasticity, the preservation of functional tissues and the functional release due to seizure freedom and drug load reduction.

Pediatric functional hemispherectomy: outcome in 92 patients.

BACKGROUND: The revival of epilepsy surgery after the introduction of modern presurgical evaluation procedures has led to an increase in hemispherectomy or hemispherotomy procedures. Since a large part of our pediatric series was done using a newer hemispherotomy technique, we focus mainly on the outcomes after a recently developed hemispherotomy technique (transsylvian keyhole). METHODS: Ninety-six pediatric patients (aged 4 months to 18 years, mean 7.3) were operated on between 1990 and 2009; 92 were available with follow-up. RESULTS: The most frequent diagnosis was porencephaly in 46 % of all patients. Progressive etiologies were present in 20 % and developmental etiologies in 22 %. At last available outcome (LAO), 85 % of the patients were seizure free (ILAE class 1). Year-to-year outcome was rather stable; usually over 80 % were class 1 for up to 13 years (n = 24). Of 92 assessable patients, 71 were treated with the transsylvian keyhole technique, with 89 % being seizure free. The overall shunt rate was 5.3 % for the whole series and 3 % for the keyhole technique subgroup. Mortality was 1 of 96 patients. Excluding patients with hemimegalencephaly (HME), patients with the shortest duration of epilepsy and the lowest age at seizure onset had the highest rates of seizure freedom. The etiology does influence outcome, with HME patients having the poorest seizure outcome and patients with Sturge-Weber syndrome and porencephaly having excellent seizure control. CONCLUSION: Hemispherotomies/functional hemispherectomies are very effective and safe procedures for treating drug-resistant epilepsy with extensive unihemispheric pathology. Etiology and surgery type clearly influence seizure outcome.

Clinical and neuropsychological characteristics of pediatric epilepsy patients with atypical language dominance.

Studies on intracarotid amobarbital procedures (IAP) in pediatric patients are rare and mainly focus on practicability aspects. Very few studies have reported characteristics of children with atypical language dominance. We compared children with left-sided focal epilepsy and atypical (i.e., right or bilateral) versus left-sided language representation (n=12 versus 17). Our results indicate a higher incidence of left handedness, extratemporal lesions, an earlier onset of epilepsy, and a neuropsychological "crowding effect" with distinct nonverbal memory deficits in the atypical group. We conclude that atypical language representation in children with left-sided epilepsy is associated with similar characteristics as in adults. It is recommended that the possibility of a language shift in the presurgical workup of pediatric patients be considered, particularly if a left-hemispheric epileptic focus is suspected.

Postsurgical outcome of children and adolescents with medically refractory frontal lobe epilepsies.

OBJECTS: In the adult population surgical treatment is generally less favorable for refractory frontal lobe epilepsy (FLE) than for temporal lobe epilepsy (TLE). Predictive factors and outcome of FLE surgery had not previously been described for the pediatric and adolescent population. Therefore, 32 children and adolescents who underwent FLE surgery were analyzed in this study. METHODS: Medical records were reviewed for demographic data, presurgical evaluation procedures, surgical procedures, pathological findings and follow-up. RESULTS: Mean age at operation was 10.8 years, with seizure onset at 4.6 years. Excellent outcomes were observed in 21 of the 32 patients following evaluation a mean of 34.5 months after surgery. Nineteen of 22 patients became seizure free after tailored resections, versus 2 out of 10 after lobectomy. Transient neurological and surgical complications occurred in 4 patients. Focal neoplastic lesions detectable by MRI were associated with a favorable outcome. CONCLUSIONS: As seen in adult FLE series, the detection of a resectable ictal neoplastic lesion on preoperative MRI is associated with an excellent outcome comparable to that of TLE surgery.

Behavioural disorders in children with epilepsy: early improvement after surgery.

OBJECTIVES: Epilepsy surgery has proved to be a successful intervention method to achieve freedom from seizures or seizure relief in children with pharmacoresistant epilepsy. Long term studies on operated children suggest that behavioural disorders, which are often seen before surgery, improve after surgery. However, the early postoperative development of behavioural problems has not been systematically evaluated. METHODS: Parents of 28 children with pharmacoresistant focal epilepsies completed the child behaviour checklist (CBCL) preoperatively and 3 months after surgery. Surgeries comprised 24 focal resections (13 temporal, 11 extratemporal), two hemispherectomies, and two callosotomies. Twenty eight conservatively treated children with comparable CBCL scores served as a control group. A repeated measurement multivariate analysis of variance (MANOVA) and a regression analysis were computed to compare the development of behaviour between both groups and to identify predictors of postoperative changes in behaviour. RESULTS: Preoperatively 39% of the children exhibited significant behavioural problems, a further 11% were within the borderline range. The MANOVA disclosed a significant interaction between time of examination and group (F=2.23, p<0.05). The surgery group showed significant improvements on the scales "internalising problems", "externalising problems", "attention problems", and "thought problems". Behavioural problems in the control group, however, remained unchanged. No changes were seen in social problems in both groups. The significant predictor of total behavioural improvement was a good seizure outcome (R(2)=0.11, p<0.05). Age, sex, onset, and duration of epilepsy, the site of the focus, and changes in antiepileptic drug regimen did not influence changes in behaviour. CONCLUSIONS: The data demonstrate an early improvement of behavioural problems after epilepsy surgery in children. The behavioural improvements can be assumed to result directly from the removal of the epileptic focus. They are not predictable on the basis of information available preoperatively, but depend on the seizure outcome.

Early childhood MRI findings in complex partial seizures and hippocampal sclerosis.

Magnetic resonance imaging (MRI) was performed on an infant with typical complex partial seizures. Visual analysis revealed MRI signs of left hippocampal sclerosis (HS) at an age of 9 months. Morphometric data including volumetry and relaxometry confirming the diagnosis are shown. This is the first report of an infant younger than 2 years with typical MRI findings including morphometric data on HS.