partial complex epilepsy

Partial complex epilepsy

DR MOHAMMAD A.S KAMIL

COSULTANT NEUROLOGIST

Background

O A complex partial seizure starts focally within the brain and causes impairment of consciousness.

O This definition is based on both clinical and electroencephalographic (EEG) data.

O A complex partial seizure is most commonly a manifestation of temporal lobe epilepsy, but the term is so broadly defined (ie, as any focal seizure with impairment of consciousness) that it is very nonspecific.

O For this reason, many clinicians make a point of distinguishing between temporal and extratemporal complex partial seizures.

Pathophysiology

O Single-photon emission computed tomography (SPECT) ictal studies show hypoperfusion of the bilateral frontal and parietal association cortex and hyperperfusion of the mediodorsal thalamus and rostral brainstem.

O Ictal effects on these structures resulting from the spread of epileptic discharges or a transsynaptic mechanism may mediate impaired consciousness during complex partial seizures.

O Pathologic studies suggest focal changes that include neuronal loss, reorganization, neurogenesis, and altered neurotransmitter receptors.

Etiology

O Hippocampal sclerosis (mesial temporal lobe)

O Neoplasms

O Cortical malformations

O Vascular malformations

O stroke

O Central nervous system (CNS) infections

O Immune-mediated CNS inflammation

O Hypoxic-ischemic brain injury

O Head trauma

O Inheritable conditions

O Febrile seizures, especially complex, are associated with an increased risk of later development of complex partial seizures and epilepsy.

Epidemiology

O The prevalence of epilepsy is approximately

0.5-1 case per 100 persons.

O Complex partial seizures occur in about

35% of persons with epilepsy.

O The incidence of partial seizures in people

younger than 60 years is 20 cases per

100,000 person-years.

O This figure rises to 80 cases per 100,000

person-years in people aged 60-80 years.

Prognosis

O The mortality rate in individuals with epilepsy is 2-3 times that in the general population.

O Most deaths are due to the underlying cause (ie, epilepsy) with the remainder due to accidents, sudden unexpected death in epilepsy (SUDEP), and suicides. SUDEP has no apparent cause.

O It occurs in 1 in 2500 persons with mild epilepsy and 1 in 250 persons with severe epilepsy.

O SUDEP is most common among those with frequent or medically intractable seizures.

O Individuals with epilepsy are at increased risk for trauma, burns, and aspiration.

History

O direct observation or from video recordings , but this is relatively rare because most patients with epilepsy never have video recordings.

O Thus, in most situations, symptom assessment is based on history alone.

O For this reason, a purely semiologic classification has been proposed and is in use at some centers.

O In this system, seizure types include autonomic, dialeptic, simple motor (clonic, tonic, tonic-clonic, epileptic spasm, myoclonic, versive), complex motor (automotor, hypermotor, gelastic), and negative (aphasic, astatic, atonic, akinetic, hypomotor, negative myoclonic).

O A thorough history should be obtained from the patient, the family members, and any relevant witnesses.

Aura

O An aura is a subjective sensation and is a simple partial seizure (ie, the initial part during which the patient is aware).

O Typically, it is of brief duration, rarely lasting longer than seconds.

O Determining the type of aura present is critical for identifying the site of cortical onset.

O Eight different varieties are recognized: somatosensory, visual, auditory, gustatory, olfactory, autonomic, abdominal, and psychic.

O Auras precede temporal lobe seizures in approximately 80% of cases.

O The most common auras in temporal lobe seizures are abdominal (a rising epigastric sensation) and psychic aura (fear, déjà vu, jamais vu).

O Temporal-parietal-occipital seizures may produce more formed auras.

Impaired consciousness O Usually, during a complex partial seizure, a patient is unresponsive and

does not remember events that occurred.

O Consciousness may not be impaired completely.

O Although patients typically do not respond to external stimuli, they may make simple verbal responses, follow simple commands, or continue to perform simple or, less commonly, complex motor behaviors (eg, operating a car).

O Impairments in consciousness should be contrasted with psychic automatisms, in which the patient experiences intense feelings of strangeness.

O Complex partial seizures are roughly equivalent to what used to be known as psychomotor seizures.

O In the semiologic classification, they are equivalent to automotor seizures (automatisms), whereas seizures with alteration of consciousness without motor phenomena are known as dialeptic seizures.

Automatisms O Automatisms are nonpurposeful, stereotyped, and repetitive behaviors

that commonly accompany complex partial seizures (in the semiologic classification, they define automotor seizures).

O The behavior is inappropriate for the situation.

O Verbal automatisms range from simple vocalizations, such as moaning, to more complex, comprehensible, stereotyped speech.

O The most common automatisms, at least in temporal lobe epilepsy, are oral (eg, lip smacking, chewing, swallowing) and manual (eg, picking, fumbling, patting]).

O Unilateral manual automatisms accompanied by contralateral arm dystonia usually indicates seizure onset from the cerebral hemisphere ipsilateral to the manual automatisms.

O Automatisms can also be more elaborate, coordinated movements involving bilateral extremities.

O Bizarre automatisms, such as alternating limb movements, right-to-left head rolling, or sexual automatisms, may occur with frontal lobe seizures.

O Oroalimentary Lip smacking, tongue

movements,chewing, swallowing, teeth grinding

O Mimetic Acting out the patient’s emotional state

O Manual or pedal Fumbling, tapping, grasping

movements

O Gestural Movement, often in response to external stimuli

O Ambulatory Wandering, walking, running

O Vocal Single or repetitive utterances, not words

O Verbal Single or repetitive utterances,

words, or sentences

O Hypokinetic Behavioral arrest, motionless

limbs

O Hyperkinetic Large-amplitude movements

of proximal limbs or trunk, such as pedaling,

thrashing, rocking, or pelvic thrusting

O Gelastic Bursts of laughter without mirth

O Dacrystic Bursts of crying without sadness

Temporal versus extratemporal seizures

O Complex partial seizures can arise from any location but most commonly arise from the temporal lobe (60%).

O Temporal lobe seizures have highly specific behaviors as compared with extratemporal seizures.

O Complex partial seizures of temporal lobe origin often begin with a motionless stare followed by oral or manual automatisms.

O Frontal lobe seizures often begin with vigorous motor automatisms or stereotyped clonic or tonic activity.

O Extratemporal lobe seizures may spread quickly to the frontal lobe and produce motor behaviors similar to those associated with complex partial seizures of the frontal lobe.

Features of Focal Seizures by Region of Onset

Temporal Lobe Seizures

Mesial Temporal O Aura (often epigastric, psychic, affective, olfactory)

O Impaired consciousness

O Fixed stare, widened palpebral fissures

O Early oroalimentary automatisms

O Limb automatisms (ipsilateral to seizure focus)

O Dystonic posturing or clonus (contralateral to seizure focus)

O Postictal confusion and amnesia

Lateral Temporal O Aura (often auditory hallucinations, complex perceptual or experiential

hallucinations, language dysfunction)

O Late oroalimentary automatisms

O Late manifestations may be indistinguishable from mesial temporal

Frontal Lobe Seizures

O Brief seizures, often in clusters

O Little or no postictal confusion

O Rapid secondary generalization

O Prominent motor manifestations (clonic, tonic, postural)

O Hyperkinetic complex or bizarre automatisms

O Sexual automatisms

O Frequent falls

O Nocturnal predominance

O Status epilepticus

Occipital Lobe Seizures

O Elementary visual hallucinations

O Loss of vision

O Sensation of eye movement

O Contralateral or ipsilateral deviation of the eyes

O Forced blinking

O Variable spread to:

Parietal lobe (sensory symptoms)

Temporo-occipital regions (formed visual hallucinations)

Mesial temporal region

Parietal Lobe Seizures

O Somatosensory auras

O Receptive language disturbance (dominant

hemisphere)

O Neglect (nondominant hemisphere)

O Variable spread to:

Occipital lobe (visual hallucinations)

Mesial temporal region

Precentral regions (motor)

Physical Examination

O The physical examination is directed so as to

elucidate focal cortical neurologic findings,

such as aphasia, unilateral neglect, apraxia,

or unilateral signs.

O In the vast majority of patients with focal

epilepsies and complex partial seizures, the

neurologic examination yields normal

results.

Differentials

O Absence Seizures

O Aphasia

O Apraxia and Related Syndromes

O Benign Childhood Epilepsy

O Benign Neonatal Convulsions

O Confusional States and Acute Memory Disorders

O Epilepsia Partialis Continua

O Epilepsy, Juvenile Myoclonic

O Epileptic and Epileptiform Encephalopathies

O Parasomnias

O Psychogenic Nonepileptic Seizures

Approach Considerations

O Laboratory studies aim to rule out potential

causes or triggers for seizures.

O Routine workup for all patients should

include electroencephalography (EEG) and

magnetic resonance imaging (MRI) of the

brain; most of the time, the results will be

normal.

Lab Studies

O Electrolyte levels, including sodium,

potassium, magnesium, and calcium

concentrations, should be assessed.

O If antiepileptic drugs are being used, drug

concentrations should be obtained.

Consider a urine drug screen.

Magnetic Resonance Imaging of Brain

O The purpose of the initial brain MRI is to exclude an obvious structural lesion as the cause.

O The procedure should include contrast with gadolinium to allow assessment of possible neoplastic and vascular etiologies.

O More subtle etiologies, such as mesial temporal sclerosis (MTS) and cortical dysplasia, only become important if the seizures prove intractable and surgery is considered.

O MRI with temporal cuts gives attention to hippocampal volumes in assessment for temporal lobe epilepsy.

O Hippocampal atrophy predominates as seizures are maintained throughout the life of a patient with temporal lobe epilepsy.

O Subtle cortical changes due to cortical dysplasia are often overlooked.

Increased signal on fluid-attenuation inversion recovery (FLAIR) T2-weighted MRI can detect

sclerosis of the mesial temporal lobe in 80-90% of cases

MRI shows right temporal lobe cavernous

hemangioma in a patient being considered

for epilepsy surgery

Electroencephalography

O EEG within 24 hours is more sensitive for diagnosing

epileptiform abnormalities than later EEG is (51%

sensitivity vs 34%), but it is often impractical.

O When epileptiform discharges are present, they help

localize the seizure focus .

O A negative interictal EEG does not exclude a

diagnosis of epilepsy.

O If the waking EEG is negative, a sleep-deprived EEG

may demonstrate epileptiform abnormalities

Lumbar Puncture

O may be indicated for a patient with new-

onset seizure when an acute inflammatory

or infectious process is being considered.

O However, it is not indicated in patients with

chronic epilepsy.

Anticonvulsant Therapy

O treatment with antiepileptic medication

should always be initiated once a diagnosis

of epilepsy is made.

O All current antiepileptic drugs (AEDs), with

the exception of ethosuximide, can be used

in the treatment of complex partial seizures.

O Monotherapy is always initially preferred

over polytherapy for treating seizures.

Surgical Treatment of Epilepsy

O is indicated for patients who have frequent, disabling seizures despite adequate trials of 2 or more anticonvulsants.

O Two recent studies reported slightly better results: after treatment with multiple AEDS, 11%6 and 16%7 became seizure free. It is interesting that 52% of patients treated surgically in one of these studies became seizure free.

O ‘‘New’’ AEDs do not appear to be more effective than older drugs.

O Surgical procedures include temporal lobectomy, extratemporal resections, corpus callosotomy, placement of a vagus nerve stimulator, hemispherectomy, and multiple subpial transection.

O The hallmark pathology of medial temporal lobe epilepsy (TLE) ismesial temporal sclerosis (MTS), found in approximately 65% of patients with intractable partial epilepsy.

O Surgically excised hippocampus in these patients almost invariably shows focal cell loss and gliosis.

O An anterior temporal lobectomy is the most common operative procedure for intractable partial epilepsy.

O Although higher figures are cited routinely, in the only controlled study, 58% of surgically compared with 8% of medically treated patients were free of disabling seizures at 1 year.

O Favorable prognostic indicators include an early

age of seizure onset, medial temporal lobe

seizure onset, and pathologically identified MTS

or foreign-tissue lesion

O In one series, approximately 90% of patients with

concordant MRI-identified hippocampal atrophy

and interictal temporal epileptiform discharges

had an excellent operative outcome.

O The outcome of surgical treatment in non

lesional TLE is less favorable.

O Bell and colleagues assessed the seizure

outcome of 40 patients who underwent an

anterior temporal lobectomy with a normal MRI

head study,

O Twenty-four of 40 patients were seizure free

after surgery.

O Patients with normal left hippocampal volumes

preoperatively may also be of greater risk for the

development of memory problems after surgery.

Thank you Neuroscinces hospital