Autonomic epileptic seizures (non-motor, autonomic -188.8.131.52 and 3.0 - autonomic events) are probably the most common of the "seizures that don't look like seizures." Fortunately these phenomena usually occur during the course of a complex partial seizure or as a prelude to a generalized tonic-clonic seizure. The pathways involved can be afferent or efferent (33). Once more, in the absence of another etiology, any isolated, recurring, paradoxical autonomic complaint should be investigated as a possible ictal manifestation. Effects on the heart have been best studied, with tachycardia occurring in a large percent of complex partial seizures (CPS) or generalized tonic-clonic (GTC) seizures (34). Tachycardia has been reported in 92 to 96% of seizures (35). A recent report on temporal lobe epilepsy (TLE) found that the percentage was highest in mesial temporal epilepsy (92%) and lowest in nonlesional cortical temporal epilepsy (77%; 35a). One early study suggested that tachycardia and pressor responses were more commonly produced by left-sided insular stimulation, with bradycardia and hypotension more common with right-sided stimulation (36). One review of ictal bradycardia reported that 76% of sixty-three reported cases were associated with frontotemporal epilepsy with left-sided ictal predominance, and that the condition is potentially lethal (37). It occurred only 1.4% of the time in a recent report on TLE. Other arrythmias have been reported, such as ventricular ectopy, Atrioventricu-lar nodal escape, and ventricular tachycardia (38). No precise cerebral location exists for these changes although the paralimbic or limbic cortex is generally implicated (39). Stimulation of either the cingulate gyrus or the insula can produce heart rate and blood pressure changes (37,40).
Chills and pilomotor erection are a common accompaniment of temporal lobe seizures but occur rarely in isolation (41) and can eminate from hippocampus, amygdala, or insula (42,43). A single case of unilateral flushing has appeared (44). Pallor or rubor can accompany temporal limbic seizures (45,46).
Pupillary dilatation is common in partial complex or generalized seizures. However, this can be asymmetric or unilateral, with the enlarged pupil appearing contralateral to a frontal source or spread pattern and can occur in isolation (47,48). Urinary incontinence is also common in generalized seizures, where it occurs due to the relaxation of the external sphincter (49). In absence seizures, it occurs (albeit infrequently) due to increased bladder pressure (50). Urinary incontinence is exceedingly rare in isolation, but one case is described in the text.
Case Study #6. A 15-year-old boy was admitted for uncontrolled seizures of several types. On video-EEG he was seen to stop his activity (writing) and look thoughtful, then abruptly to push his chair away from the table and look down at his lap in surprise. He called the nurse to say "I had a little flash." When asked what he meant he reported that he had had a seizure and wet himself. The origin of this patient's epileptic seizures was widespread areas of the frontal lobe, including some clearly starting in the cingulate gyrus. Isolate enuresis was not recorded on intracranial monitoring (51).
Gastrointestinal symptoms are also common ictal phenomena. These include flatulence, epigastric rising sensations, borbyrigmy, nausea, and emesis (52-56). These symptoms are frequently isolated in children. Ictal emesis, in particular, has been described from the insula, the frontal operculum, and in benign occipital epilepsy. Ictus emeticus can occur without impairment of awareness and in isolation (57). Rectal pain and burning may occur in an epileptic seizure and can be triggered by a bowel movement (58).
Respiratory symptoms are also common. These can include hyperventilation during CPS and hypoventilation during or after generalized tonic-clonic seizures (59). However, difficulty breathing, choking, stridor, and apnea can also occur (60-62). Stimulation of the temporal lobe, insula, hippocampus, anterior cingulate, amygdala, and lower motor cortex have been shown to induce respiratory inhibition (46,63,64). The differential diagnoses of autonomic phenomena includes gastrointestinal disease, endocrine diseases such as pheochromocytoma, cardiac disease, and psychiatric disease especially panic attacks (65).
Genital sensation with sexual content and sexual auras arise more commonly from limbic or temporal lobe regions (66). Ictal orgasm or priapism have also been reported (67). Other types of sexual automatisms have been described (68,69). These are motor automatisms (pelvic thrusting) from the frontal lobe and genital sensations (from parietal or limbic structures).
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