[Limbic ictus as a condition for anxiety attacks]

Episodes of anxiety have been reported to be the most common psychological symptoms in patients with partial seizures. They may occur before, during and after seizures and can also appear in isolation without any convulsive symptoms. The epileptic anxiety syndrome is strikingly similar to panic attacks, and panic disorder is an important differential diagnosis. The close relationship between epileptic seizures and panic attacks is of special interest for a better pathophysiological understanding of panic attacks. In the literature an epileptiform neuronal activity is discussed as a possible underlying mechanism for panic disorder. The finding that anxiety was the most common experiential phenomenon produced by electrical stimulation of amygdala and hippocampus with depth electrodes points in this direction. PET has demonstrated abnormalities of hippocampal structures during the nonpanic state of patients with panic disorder. In addition, some EEG studies have demonstrated a high incidence of epileptiform EEG patterns in patients with panic disorder with or without agoraphobia. This was the reason why several investigators proposed that a subset of panic attacks may be related to abnormal epileptiform neuronal activity in the limbic system. The size of this subset is difficult to determine because discharges in the depth of the limbic system often cannot be seen in the scalp EEG. Concerning the hypothetical pathophysiological mechanism of panic disorder therapeutic measures were taken with antiepileptic agents. The best results were obtained for valproic acid. It seems to be reasonable to make a therapeutic trial with antiepileptic medication after nonresponse to standard pharmacotherapy.