Simple Partial Seizure

A seizure is a symptom that refers to episodic, excessive, and disorderly neuronal activity in the brain. Traditionally seizures have been classified into and generalized. Partial seizure refers to abnormal neural activity localized to one area of the cerebral hemisphere and having a discernible or localized onset. When there is no associated impairment in consciousness, it is called a simple seizure, and when it is associated with impairment in consciousness, it is called a complex seizure. When a seizure becomes generalized, it is referred to as a partial seizure with secondary generalization. New terminology for a simple seizure is focal onset aware seizure.Partial seizures are the most common type of seizures in patients with epilepsy. Complex seizures occur more often than simple seizures, although most complex seizures start as simple seizures.Patients with simple seizures remain awake and aware throughout the seizure, and some patients can even talk during the episode. It may be difficult to distinguish them from complex seizures in infants and patients with cognitive and speech difficulties, as impairment in consciousness can be difficult to assess in these patients.The term aura refers to signs and symptoms that occur with a seizure before consciousness is lost and for which memory is intact afterward. Auras that are not followed by seizure should be considered aware seizures or simple seizures.Depending on clinical signs, symptoms, and EEG localization, seizures can be further subdivided into four types: Focal motor seizures Focal sensory seizures Autonomic seizures Psychological seizures Focal Motor Seizures The or motor seizure occurs due to an epileptogenic lesion on the contralateral frontal lobe. Motor symptoms constitute the primary clinical manifestation. Typically, consciousness is not impaired in seizures of discrete motor areas. They usually originate from the supplementary motor area and cause turning movements of the head and neck to the opposite side and sometimes tonic contractions of the limbs and trunk on the same side. This may or may not be followed by generalized clonic movements. Subdivisions of ictal motor symptoms include elementary (tonic, clonic, dystonic, versive) and automatism (coordinated, repetitive motor activity like lip-smacking, tapping, and swallowing). Another classification based on clinical symptomatology uses the terms like clonic, tonic, or versive seizures.Focal motor seizures are more common on the face, hands, and toes because these areas have disproportionately large cortical representations. The excitatory focus is usually around the rolandic (motor) cortex. If there are accompanying sensory symptoms, the focus may be on post-rolandic convolution. Temporal lobe origin seizures sometimes have head-turning movements on the same side followed by the forceful contraversive turning of the head and body. Clonic seizures refer to repeated, short contractions of various muscle groups characterized by twitching movements or rhythmic jerking that recur at regular intervals of less than 1 to 2 seconds. These seizures are brief, lasting less than one to two minutes. In clonic seizures, there is epileptic activation of a restricted area of the precentral gyrus. Tonic seizures refer to sustained contractions that last for more than 5 to 10 seconds and result in the posturing of the limbs and whole body. Focal tonic seizures refer to tonic contractions restricted to a part of the body on one side. Focal tonic seizures are attributed to activation of Brodmann area 6, particularly the mesial frontal region. There may be some involvement of the premotor areas in some cases. Versive seizures consist of sustained, forceful, involuntary turning of head and eyes to one side due to tonic contraction of head and eye muscles. Usually, they are accompanied by loss of consciousness, but occasionally patients may be aware of the forced involuntary eye and head-turning. The version can result from seizures originating from various locations and spreading to the premotor cortex. Following convulsions with predominant motor symptoms, patients may have transient, functional, and localized paralysis of the affected limbs. This is known as Todd paralysis and can last minutes to hours, usually in proportion to the duration of the convulsion. This postepileptic paralysis occurs due to persistent dysfunction of the affected epileptogenic area and is the signature of a seizure. It has significant clinical value in lateralizing the hemisphere of seizure onset. Jacksonian March Seizure Jacksonian march seizure starts with tonic contractions in one hand or on one side of the face or the muscles of one foot. This is followed by clonic movements in these parts and sometimes a series of clonic movements with increasing frequency that builds up to a tonic contraction. These movements may spread (march) from the muscles affected to the other muscles on the same side of the body. In classic Jacksonian march, the seizure spreads from hand to arm to face and then down the leg ipsilaterally, or if it started in the foot, then seizure marches up the leg, down the arm, and then to the face. This typically happens over a short time (20 to 30 seconds). There can be other associated symptoms like automatism (lip smacking or tapping movements), hallucinations, muscle cramping, head-turning, etc. Symptoms are usually mild. These seizures rarely become generalized, and typically consciousness remains intact. Jacksonian march seizure can be mistaken for a transient ischemic attack, migraine, or other condition. Focal Somatosensory Seizures Sensory seizures present as numbness, tingling, crawling sensation, pins and needles feeling, and rarely, as pain or thermal sensations. They can be or can march to other ipsilateral body parts and usually have a focus in or around post-rolandic convolution of the contralateral cerebral hemisphere. Visual seizures are rare but have localizing significance. Visual hallucinations and visual loss are typical of occipital lobe epilepsy but sometimes can occur with seizure foci in anteromedial temporal and occipitotemporal regions. Auditory hallucinations are a rare initial manifestation of seizure and have sometimes been noted with lesions in the posterior temporal lobe on one side. Olfactory hallucinations often occur with a lesion in the inferior and medial parts of the temporal lobe. Gustatory hallucinations can occur in temporal lobe disease with lesions in the insula and parietal operculum. Autonomic Seizures Autonomic seizures manifest with predominantly altered autonomic function. Some common autonomic signs and symptoms include diaphoresis, shivering, piloerection, a rising sensation in epigastrium, nausea, changes in blood pressure and heart rate (commonly tachycardia), and pupillary changes. Autonomic features are common in several nonepileptic conditions, making autonomic seizures harder to diagnose.Some specific epilepsy syndromes with prominent autonomic features include neonatal seizures, epilepsy of infancy with migrating seizures, Dravet syndrome, benign epilepsy with centrotemporal spikes, and early-onset benign occipital epilepsy. Psychological Seizures Psychological seizures manifest with affective and cognitive symptoms like memory flashbacks, dream-like events, Deja Vu feeling, hallucinations, anxiety, agitation, and uncontrolled laughter or crying. They arise commonly from the temporal area rather than the extratemporal.