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Contaminations with radioactive material may occur in several situations related to medicine, industry or research. Seriousness of the incident depends mainly on the radioactive element involved; usually there are no major acute health effects, but in the long term can cause malignancies, leukemia, genetic defects and teratogenic anomalies. The most common is superficial contamination, but the radioactive material can get into the body and be retained by the cells of target organs, injuring directly and permanently sensitive elements of the body. Rapid intervention is very important to remove the radioactive material without spreading it. Work must be performed in a specially prepared area and personnel involved should wear special protective clothing. For external decontamination general cleaning techniques are used, usually do not require chemical techniques. For internal decontamination is necessary to use specific agents, according to the causative element, as well physiological interventions to enhance elimination and excretion.

Drug-resistant epilepsy can sometimes be treated by surgery. In these cases, an accurate identifi cation of the epileptogenic area must be addressed before resection. Ictal SPECT is one of the presurgical evaluations that can be performed, but usually, the increase in the regional cerebral perfusion observed is produced by diffusion of ictal activity. Here we describe a patient studied with v-EEG and foramen ovale electrodes that suffered a seizure after intravenous infusion of etomidate. The sequence of etomidate administration, followed by radiotracer and seizure was good enough for us to suspect that a true initial ictal SPECT was observed. We have implemented a kinetic model with four compartments, previously described (Andersen 1989), in order to estimate the fraction of hydrophilic radiotracer in the brain during the pre-ictal and ictal periods. This model has shown that the fraction of hydrophilic radiotracer during the seizure into the brain would be between 18.9% and 42.3% of total infused. We show the fi rst true initial ictal SPECT demonstrated by bioelectrical recordings of the brain activity, obtained by a correct succession of events and compatible with theoretical data obtained from the kinetic model.

SUMMARYPurpose: A variety of drugs have been used to activate and identify the epileptogenic area in patients during presurgical evaluation. We have evaluated the safety and usefulness of etomidate in identifying the epileptic zone by measuring bioelectrical brain activity and cerebral blood flow (CBF). Methods: We studied 13 men and 9 women under presurgical evaluation for temporal lobe epilepsy. We applied etomidate (0.1 mg/kg) while patients were monitored by video-electroencephalography (VEEG) with foramen ovale electrodes. In a subset of 15 patients, we also measured CBF with single photon emission computed tomography (SPECT). (6) The kinetics of pharmacologically induced activity was higher in the region of the ictal-onset zone. (7) Etomidate increased the CBF in the basal ganglia and especially in the posterior hippocampus of the temporal mesial region contralateral to the ictal-onset zone. Discussion: Etomidate activation is a safe, specific, and quick test that can be used to identify the epileptic region in patients evaluated as candidates for temporal lobe epilepsy surgery.

Introduction. Recently, we have published the results of a first surgical series of patients with temporal lobe epilepsy (TLE). We describe a posterior series of patients intervened of TLE, we compare the functional results with the previous series and we finally analyze the causes of changes. Patients and methods. We studied the first 22 consecutive patients surgically intervened of TLE with a minimum post-surgery follow-up of 2 years. Patients showing I and II Engel's grade were used as gold standard for evaluation of pre-surgical complementary studies. Results. We have obtained better functional results: 91% patients showing Engel's grade I, 9% showing grade II and neither III nor IV grades were obtained. Pre-surgical studies changed in comparison with the previous report. The most improving change was observed in video-EEG with foramen-ovale electrodes (FOE) (37%), scalp EEG (26.6%), interictal SPECT (11.7%) and MRI (11.7%). Video-EEG with FOE was the study than showed greater concordance with epileptic focus (95.5%), followed by EEG (86.4%). In 35% of cases, MRI was normal or without valid data for correct localization of focus. Conclusions. Video-EEG with FOE and TLE surgery are safety methods, which results improve with the experience. Normal or not informative MRI do not should a priori reject those patients with drug-resistant TLE from surgery.