Vagus nerve stimulation is an effective and safe adjunctive treatment for patients with refractory partial-onset seizures. It represents the advent of a new, nonpharmacologic treatment for epilepsy.

Summary:Purpose: To determine the long-term efficacy of vagus nerve stimulation (VNS) for refractory seizures. VNS is a new treatment for refractory epilepsy. Two short-term double-blind trials have demonstrated its safety and efficacy, and one long-term study in 114 patients has demonstrated a cumulative improvement in efficacy at 1 year. We report the largest prospective long-term study of VNS to date.Methods: Patients with six or more complex partial or generalized tonic-clonic seizures enrolled in the pivotal E05 study were prospectively evaluated for 12 months. The primary outcome variable was the percentage reduction in total seizure frequency at 3 and 12 months after completion of the acute E05 trial, compared with the preimplantation baseline. Subjects originally randomized to low stimulation (active-control group) were crossed over to therapeutic stimulation settings for the first time. Subjects initially randomized to high settings were maintained on high settings throughout the 12-month study.Results: The median reduction at 12 months after completion of the initial double-blind study was 45%. At 12 months, 35% of 195 subjects had a >50% reduction in seizures, and 20% of 195 had a >75% reduction in seizures.Conclusions: The efficacy of VNS improves during 12 months, and many subjects sustain >75% reductions in seizures. Key Words: Vagus nerve stimulation-Intractable epilepsy.Vagus nerve stimulation (VNS) has emerged as an effective treatment for medically intractable epilepsy ( 1-3). VNS uses an implantable, programmable pulse generator powered by a lithium battery, which is connected to a helical bipolar lead. The lead is attached to the midcervical portion of the left vagus nerve and delivers

Objective: To investigate the relationship between white matter tract integrity and language and memory performances in patients with temporal lobe epilepsy (TLE). Results: Increases in MD of the left UF, PHC, and IFOF were associated with poorer verbal memory in TLE, as were bilateral increases in MD of the AF, and decreases in FA of the right AF. Increased MD of the AF and UF, and decreased FA of the AF, UF, and left IFOF were related to naming performances. No correlations were found between DTI measures and nonverbal memory or fluency in TLE. Regression analyses revealed that several fibers, including the AF, UF, and IFOF, independently predicted cognitive performances after controlling for HV. Methods Conclusions:The results suggest that structural compromise to multiple fiber tracts is associated with memory and language impairments in patients with temporal lobe epilepsy. Furthermore, we provide initial evidence that diffusion tensor imaging tractography may provide clinically unique information for predicting neuropsychological status in patients with epilepsy. Neurology ® 2008;71:1869-1876 GLOSSARY AF ϭ arcuate fasciculus; BNT ϭ Boston Naming Test; CST ϭ corticospinal tract; DTI ϭ diffusion tensor imaging; FA ϭ fractional anisotropy; FORX ϭ fornix; HV ϭ hippocampal volume; ICHV ϭ intracranial-adjusted HV; IFOF ϭ inferior frontooccipital fasciculus; LM ϭ Logical Memory; MD ϭ mean diffusivity; MTS ϭ mesial temporal sclerosis; PHC ϭ parahippocampal cingulum; TLE ϭ temporal lobe epilepsy; UF ϭ uncinate fasciculus; WMS-III ϭ Wechsler Memory Scale-Third Edition.Global and lobar white matter atrophy has been reported in patients with temporal lobe epilepsy (TLE), 1,2 and an association between global white matter volume loss and generalized cognitive dysfunction has been described.2 However, the relationships among local white matter changes and cognitive impairments in TLE have not been established. Diffusion-tensor imaging (DTI) is a relatively new MRI technique for investigating white matter microstructure by measuring the relative motility of water within a voxel (mean diffusivity [MD]) and its directionality (fractional anisotropy [FA]).3,4 Higher MD and lower FA values are thought to reflect factors such as demyelination and axonal injury that are important for understanding neurologic disease.5 DTI tractography is an extension of DTI that provides an in vivo method of quantifying and visualizing the integrity of Editorial, page 1854

BACKGROUND AND PURPOSE:Noninvasive imaging plays a pivotal role in lateralization of the seizure focus in presurgical patients with temporal lobe epilepsy (TLE). Our goal was to evaluate the utility of diffusion tensor imaging (DTI) tractography in TLE.

SUMMARYPurpose: To determine the nature and extent of regional cortical thinning in patients with mesial temporal lobe epilepsy (MTLE). Methods: High-resolution volumetric MRIs were obtained on 21 patients with MTLE and 21 controls. Mean cortical thickness was measured within regions of interest and point-by-point across the neocortex using cortical reconstruction and parcellation software. Results: Bilateral thinning was observed within frontal and lateral temporal regions in MTLE patients relative to controls. The most striking finding was bilateral cortical thinning in the precentral gyrus and immediately adjacent paracentral region and pars opercularis of the inferior frontal gyrus, extending to the orbital region. Within the temporal lobe, bilateral thinning was observed in Heschl's gyrus only. Ipsilateral only thinning was observed in the superior and middle temporal gyri, as well as in the medial orbital cortex. Greater asymmetries in cortical thickness were observed in medial temporal cortex in patients relative to controls. Individual subject analyses revealed that this asymmetry reflected significant ipsilateral thinning of medial temporal cortex in 33% of patients, whereas it reflected ipsilateral thickening in 20% of MTLEs. Discussion: Patients with MTLE show widespread, bilateral pathology in neocortical regions that is not appreciated on standard imaging. Future studies are needed that elucidate the clinical implications of neocortical thinning in MTLE.