Focal epileptic crisis

Focal crisisFocal epileptic crisis originate from restricted areas of the brain. Thus, these crisis manifest with specific clinical features that are the consequences of the excitability of those regions. Recognizing such clinical features and localizing them in the brain could be very important, along with EEG evaluation, medical imaging (MRI, SPECT, PET) and neuropsychological assessment to define the exact localization of the epileptic focus and take therapeutic decisions such as epilepsy surgery.
Epileptic automatisms consist of oro-alimentary movements such as lip-smacking, sucking, swallowing, chewing. They localize to the right or left mesial temporal lobe or amygdala. Ictal spitting and drinking originate from the temporal lobe. Laughter (or gelastic) crisis are related to the involvement of the hypothalamic region, the mesial temporal or frontal cingulate gyrus.
Speech disturbances consist of speech arrest, verbalizations (names, phrases or sentences), aphasia (all kind of), anomia or dysnomia, paraphasias (deformed words). Aphasia can also occur in the postictal period (when the crisis is ended). All speech disturbances point to a focus on the left or dominant hemisphere (language areas).  Speech arrest may occur also for seizures originating from the sensorimotor cortex and the supplementary motor area. Vocalizations (moaning, grunting, and screaming) are more frequently the consequences of frontal lobe seizures.
Motor signs consists of epileptic tremor or tonic spasms or myoclonus, facial and hand twitching, abnormal posture, dystonia and head and eye deviation. Motor signs could also consist (more rarely) of paralysis (atonic or drop seizures). Motor signs originate usually from contralateral motor areas. However head and eye deviation can rarely occur with occipital seizures. The figure of 4 sign (one arm is rigidly extended at the elbow while the other is flexed at the elbow) take its origin from the motor cortex which is contralateral to the extended arm. A fencing posture, and fragmentary body movements as swimming or pedaling suggests the involvement of the contralateral frontal lobe and supplementary motor area.
Sensory symptoms consist generally of “pins and needle” that march in few seconds from the hand to the face or to the ipsilateral limb and originate from the contralateral somatosensory areas (rarely ipsilateral). Pain is a rare symptom of focal seizures but it can also occur.
Auditory symptoms are not so rare and consist of hearing (from one or both ears) chirping or buzzing noises, ringing, having a muffled hearing. Auditory symptoms originate from the superior temporal gyrus. Vomiting (ictal emesis) or vomiting after the crisis, or heart arrhythmia (even asystole) and vertigo could originate from the insula or adjacent temporal areas. Ictal vomiting occur also with benign occipital epilepsies. Urinary urge and piloerection, salivation, blood pressure changes occur with temporal lobe epilepsy.
Temporal lobe seizure can also manifest with dreamy states, false or true memories, déja-vu and déja-vecu experiences, confabulations, fears, aggression or destructive (clastic crisis) behaviors (very rare), hypergraphy, olfactory hallucinations (uncinated crisis), poriomania (aimless wandering with successive retrograde amnesia), and nose rubbing and coughing in the post-crisis phases. Feelings of joy and ecstasies are also possible. Erotic feelings or sensations (even orgasms in few published cases) generally with negative emotions are extremely rare manifestations of epileptic crisis of the temporal lobe.
Epileptic heautoscopia (seeing one’s own body from a distant perspective) and other extracorporeal experiences which could appear similar to near-to-death experiences are related to the excitability of the temporo-parietal junction.
Occipital lobe seizures manifest with the sudden vision of simple elements such as lights, spots, lines, geometric images or complex images and scenes (people, places, and landscapes). Rarely the visual feature can consist of some loss within the visual fields.
The clinical semiology of focal epileptic crisis has a key role for investigating a seizure disorder and making the right diagnosis of focal epilepsy.

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