Faculty Bibliography

Right hemisphere functions were examined during cortical stimulation in six patients undergoing epilepsy surgery. Two patients showed mild hemispatial neglect and constructional disability with stimulation of several sites in the inferior parietal lobule and posterior temporal lobe. Two other patients showed no disruption of visuospatial functions with stimulation of similar parietal or posterior temporal sites. Nonverbal acoustic perception of environmental sounds was not disrupted with stimulation of right superior temporal cortex in one patient, and musical abilities were not affected by right superior temporal stimulation in another patient. Nondominant hemisphere functions may be more widely distributed and less localized than linguistic functions in the dominant hemisphere

Knowledge about the comparative safety and efficacy of standard and new antiepileptic drugs (AEDs) is limited. Medications are selected on the basis of seizure type and epilepsy syndrome, adverse effect profiles, and cost. However, there are few data comparing the efficacy of the new AEDs for the treatment of recent-onset versus refractory partial seizures, simple versus complex partial seizures, frontal versus temporal lobe seizures, or other relevant clinical types. Few studies compare new AEDs. The next best approach has been the use of meta-analyses and compilation of data from clinical trials, which allow interstudy comparisons to define broad and rough comparative estimates. These analyses, however, do not define clear differences in the safety and efficacy of the new AEDs because of differences in study populations. The new AEDs have expanded our arsenal against seizures. As a group, they have favorable safety and efficacy profiles. The challenge is to define the differences in terms of clinical significance

Physicians are often reluctant to use psychotropic medications in epilepsy patients with psychiatric disorders because of concern over the potential risk for lowering seizure threshold. This study assesses retrospectively the impact of psychotropic medications on seizure frequency in 57 patients seen consecutively at an epilepsy center. During psychotropic drug therapy, seizure frequency decreased in 33% of patients, was unchanged in 44%, and increased in 23%. Mean seizure frequency was not statistically different between pre-treatment and treatment periods (t = 0.23, df = 56). Simultaneous adjustments in antiepileptic drug regimen could not account for the findings. Results support the position that psychotropic medications, introduced slowly in low to moderate doses, can be safely used in epilepsy patients with comorbid psychiatric pathology during the regular course of clinical care

It is known that epilepsy patients diagnosed with neocortical temporal lobe epilepsy (NTLE), differ from those diagnosed with mesial temporal lobe epilepsy (MTLE), e.g., in hippocampal (HPC) pathology. In the present studies, we tested the hypothesis that NTLE and MTLE subtypes of human epilepsy might differ in regards to their HPC monoamine neurochemistry. Monoamine neurotransmitters were studied in separate signals and within s with semiderivative microvoltammetry, used in combination with stearate indicator, Ag-AgCl reference and stainless steel auxiliary microelectrodes. Anterior HPC specimens from the patients' epileptogenic zone, defined by electrocorticography, were resected neurosurgically from 13 consecutive patients with intractable temporal lobe epilepsy. Four patients were diagnosed with NTLE and nine with MTLE. The criteria for the diagnosis of NTLE versus MTLE was absence versus presence of HPC sclerosis, respectively, based on MRI examination of resected tissue. In addition, NTLE patients demonstrated seizure onset in anterolateral temporal neocortex on electroencephalography (EEG). HPC subparcellations studied were: (a) Granular Cells of the Dentate Gyrus (DG), (b) Polymorphic Layer of DG and (c) Pyramidal Layer: subfields, CA1 and CA2. Dopamine (DA), serotonin (5-HT), norepinephrine (NE) and ascorbic acid (AA) (co-factor in DA to NE synthesis), exhibited separate and characteristic half-wave potentials in millivolts. Each half-wave potential, i.e., the potential at which maximum current was generated, was experimentally established in vitro. Concentrations of neurotransmitters found in HPC subparcellations were interpolated from calibration curves derived in vitro from electrochemical detection of monoamines and AA in saline phosphate buffer. Significant differences between subtypes in concentration of monoamines were analyzed by the Mann Whitney rank sum test and those differences in probability distribution of monoamines were analyzed by the Fisher Exact test; in each case, P<0.01 was the criteria selected for determining statistical significance. DA concentrations were higher in NTLE compared with MTLE in each HPC subparcellation [P=0.037, 0.024 and 0.007, respectively (P<0.01)] and DA occurred more frequently in NTLE in the Pyramidal Layer [P=0.077 (P<0.01)]. AA was present in one NTLE patient. NE concentrations were higher in MTLE vs. NTLE in each subparcellation [P=0.012, 0.067 and 0.07, respectively (P<0.01)] and NE occurred more frequently in MTLE in Granular Cells of DG and Pyramidal Layer [P=0.052 and 0.014, respectively (P<0.01)]. In MTLE, NE concentrations in the CA1 subfield of the Pyramidal Layer were decreased vs. the CA2 subfield [P=0.063 (P<0.01)]. Serotonin was found in every HPC subparcellation of each subtype but 5-HT concentrations were higher in NTLE vs. MTLE in the Granular Cells of DG and the Pyramidal Layer (CA1 subfield) [P=0.076 and 0.095, respectively (P<0.01)]. Thus, this preliminary study showed that marked differences in HPC monoamine neurochemistry occurred in NTLE patients as compared with MTLE patients

Severe emotional outbursts (SEOs) during intracarotid amobarbital procedures (IAP) rarely jeopardize preoperative language and memory testing. Four of four patients (100%) with outbursts had experienced significant emotional trauma (three were raped and one witnessed a decapitation), compared with 26 of 546 patients (4.8%) without outbursts (chi2 = 69.8, p < 0. 0001). Evocative injections were ipsilateral to seizure focus. IAP may disrupt emotional balance in some traumatized patients. Counseling may prevent SEOs

Treatment options for atypical forms of Landau-Kleffner syndrome (LKS) are not well delineated. Many patients with typical LKS fail to respond to antiepileptic drug treatment, but some benefit from multiple subpial transections (MSTs). The authors report seven patients with autism or autistic epileptiform regression who responded in varying degrees to MSTs after failed medical management. These patients derived from an original cohort of 36 children (29 males, seven females, ranging from 2 years, 3 months to 11 years, 3 months, mean age = 5 years, 8 months) with a history of language delay or regression, as well as varying degrees of social and behavioral abnormalities, who were evaluated with video-electroencephalogram (EEG) monitoring over a 2-year period. Fifteen patients had clinical seizures (11 of the 19 children with autistic epileptiform regression and four of 12 autistic children). Epilepsy was refractory to medication in seven. Surgical treatment variously involved MSTs of the left neocortex in temporal, parietal, and frontal regions, often including regions within the classic perisylvian language areas. One patient also had a left temporal lobectomy. In all seven patients, seizure control or EEG improved after MSTs. Language, social, and overall behavior improved to a moderate degree, although improvements were temporary in most. Autistic epileptiform regression resembles LKS in that both may respond to MST. MST is used to treat epilepsy in eloquent regions. The responsiveness of autistic epileptiform regression to MST buttresses the argument that autistic epileptiform regression is a form of focal epilepsy