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The effect of acute treatment with the new antiepileptic drug (AED) levetiracetam (Keppra®) on the frequency of interictal epileptiform discharges (IEDs) was evaluated in a double-blind, placebo-controlled, crossover study with therapeutic drug monitoring and serial electroencephalographic (EEG) observations. Acute (500 mg twice daily) and chronic (individualized, 500–1000 mg twice daily) doses of levetiracetam were administered as an add-on to current AED treatment. Efficacy was tested by measuring the frequency of IEDs in EEG recordings and the number of seizures. A single acute dose of levetiracetam induced a reduction of IEDs in eight out of ten patients. During the acute phase, an insufficient number of seizures occurred for analysis. During chronic treatment over 8 weeks, seven patients showed a reduction in seizure frequency (responder rate), and one patient remained seizure free. No correlation was seen between levetiracetam levels and IED frequency. Doses of levetiracetam of up to 2000 mg/day were well tolerated, and no interactions were seen with concomitant AEDs.

OBJECTIVES: To describe the clinical presentation of patients with Alzheimer's disease (AD) or dementia with Lewy bodies (DLB) who were suspected of having Creutzfeldt-Jakob disease (CJD) and to investigate whether current clinical diagnostic criteria cover these atypical forms of AD and DLB. METHODS: Brains from necropsy were examined for the diagnosis of CJD at the German reference centre for spongiform encephalopathies. Symptoms and signs in patients with suspected CJD in whom necropsy showed AD (n=19) or DLB (n=12) were analysed. Their data were compared with a group of patients with CJD (n=25) to determine overlapping and discriminating clinical features. All patients were classified according to clinical diagnostic criteria for CJD, AD, and DLB. RESULTS: Demented patients were suspected of having CJD if disease was rapidly progressing and/or focal neurological signs appeared and/or an EEG showed sharp wave complexes. Myoclonus and limb rigidity were the most common neurological signs in all three dementias. DLB was not suspected in any patient, although patients with DLB showed parkinsonism (58%) and fluctuations (58%). Periodic sharp wave complexes (PSWCs) in EEG typical of CJD were found in five patients with AD and one patient with DLB. 14-3-3 Protein in CSF was detected in 20 patients with CJD, in two patients with AD, but not in any patient with DLB. Although most patients with DLB or AD met the clinical criteria for their respective diagnosis (74% and 90%), they also fulfilled criteria for CJD (42% and 58%). CONCLUSIONS: In patients with rapidly progressive dementia and focal neurological signs, CJD should be the first line diagnosis. Facing the triad dementia, myoclonus, and rigidity, AD should be considered if the disease course is longer and DLB is the differential diagnosis if parkinsonism or fluctuations are present. Findings on EEG or CSF typical of CJD do not exclude AD or DLB.

Near infrared spectroscopy (NIRS) is a non-invasive method to measure cerebral tissue oxygenation continuously with an adhesive optode system which can be easily placed on the skin. We coupled NIRS with video-electroencephalography (video-EEG) during the presurgical evaluation of two patients with intractable localization-related epilepsy of mesial temporal origin. Cerebral oxygen saturation was measured either ipsilaterally (three seizures) or contralaterally (four seizures) to the primary epileptogenic zone. Since NIRS measures cerebral tissue oxygenation in a depth of only few centimetres, it did not record within the primary epileptogenic zone in our patients. Therefore we decided to place the NIRS optodes comfortably for the patients on the hairless skin corresponding with measurement of the oxygenation within the corresponding frontal cortex. Ipsilateral measurement revealed a marked desaturation in the course of the seizure with a postictal maximum whereas contralateral findings were inconsistent. The favourable outcome of selective amygdalahippocampectomy in both cases retrospectively confirmed the correct lateralization by video-EEG and the concordant NIRS findings. Our preliminary results suggest that NIRS might be a simple, cost-effective and non-invasive additional method to lateralize the primary epileptogenic zone in temporal lobe epilepsy and should be further investigated in larger series of patients.

The first investigation of the central-type benzodiazepine (BZ) receptor density before and following 2 months successful treatment with carbamazepine (CBZ) in a patient with temporal lobe epilepsy (TLE) using ^1^2^3I-labelled Iomazenil (a specific lipophile central BZ receptor compound) and single photon emission tomography (SPET) is reported. First, a focal slowing of the EEG in the left temporal area was noted and a corresponding reduction of the central BZ density of the left temporal lobe was found. After 2 months of treatment the patient was symptom-free, and a normal BZ receptor density and no pathological EEG signs were found. The increase in central BZ receptor binding sites might be related to the anticonvulsant effects of CBZ mediated by the so-called peripheral BZ receptor sites.