Temporal lobe epilepsy also called mesial temporal lobe epilepsy, the most frequent form of partial epilepsy in adults, is clinically characterized by alterations in consciousness combined by various functional manifestations including sensory, motor, psychic, and autonomic. Lobe epilepsy tle which is the most common form of partial epilepsy. Hippocampal onset accounts for at least 80% of all temporal lobe seizures. Periodic epileptiform discharges peds are an uncommon, abnormal eeg pattern seen usually in patients with acute diseases and less frequently in chronic conditions, such as mesial temporal lobe epilepsy mtle. A range of surgical options now exist with varying degrees of efficacy. Effects of chronic temporal lobe epilepsy on memory functions. Unilateral mesial temporal lobe epilepsy how is unilateral mesial temporal lobe epilepsy abbreviated. Specific restingstate brain networks in mesial temporal lobe. Treatment of mesial temporal lobe epilepsy using mrgfus. Bernhardt bc, worsley kj, kim h, evans ac, bernasconi a, bernasconi n. Mesial peds temporal lobe epilepsy hippocampal sclerosis a b s t r a c t purpose. On the other hand, it is an often unrecognized cause of cognitive decline, typically presenting with severe memory loss. Mtle with mts is the most surgically amenable epilepsy diagnosis and the results of epilepsy surgery are clearly superior.
Aura occurs in the majority of temporal lobe seizures. Patients that are refractory to medical treatment are often considered for invasive surgery to remove the epileptogenic focus originating from the structures of the medial temporal lobe. Temporal lobe epilepsy tle is divided into two categories. Temporal lobe epilepsy tle is the commonest form of focal epilepsy and. Temporal lobe epilepsy tle is a chronic disorder of the nervous system characterized by recurrent, unprovoked focal seizures that originate in the temporal lobe of the brain and last about one or two minutes. Mesial temporal lobe epilepsy jama neurology jama network.
Evidence will be presented to demonstrate that the cognitive consequences of this focal seizure disorder can be more generalized in nature than expected. Various neuroimaging modalities are available for evaluating patients with temporal lobe epilepsy tle. People with drugresistant medial temporal lobe epilepsy have a higher risk for memory and mood difficulties. Deep brain stimulation dbs is being used with increasing frequency for the treatment of mesial temporal lobe epilepsy mtle. Aprendendo python mark lutz pdf many of the explanations for the increased incidence of these conditions in people with lower socioeconomic status ses suggest they are the result of poor diet, low levels of exercise. Teasing out the anatomy of mesial temporal lobe epilepsy. It is not intended to be and should not be interpreted as medical advice or a diagnosis of any health or fitness problem, condition or disease. The interictal mesial temporal lobe epilepsy network. Temporal lobe epilepsy remains a significant cause of disabling morbidity. Patients often complain of poor memory for recent events, and this may get worse as the epilepsy continues. Auras may cause sensory, autonomic or psychic symptoms. Early surgical intervention, when successful, might also prevent or.
Jan 01, 2001 in the 1950s, falconer stressed the importance of mesial temporal sclerosis mts in surgery for mesial temporal lobe epilepsy mtle. All patients considering surgery should undergo magnetic resonance imaging, which is valuable in the detection and characterization of lesions, particularly mesial temporal sclerosis, the most common abnormality in tle. Neuropsychology and temporal lobe epilepsy cns spectrums. Report of two pediatric cases and reconsideration of the surgical strategy.
This is so because in many patients with temporal lobe epilepsy, the surface electrodes do not pick up seizure activity. Most auras and automatisms last a very short period seconds or 1 to 2 minutes. Temporal lobe epilepsy and memory with about 70% temporal lobe epilepsy tle is the most common type of the focal symptomatic or cryptogenic epilepsies. Unitemporal vs bitemporal hypometabolism in mesial temporal. Mesial temporal lobe sclerosis mts is the major underlying cause of mtle, and it is present in 6070% of patients with mtle who undergo surgery for treatment.
The first habitual seizures usually occur in late childhood or early adolescence. Objective to compare the clinical characteristics between unitemporal hypometabolism uth and bth patients in mesial tle. Mesial temporal lobe epilepsy mtle affects the inner part of the temporal lobe manifesting in the hippocampus, parahippocampal gyrus and the amygdala. Below is a photograph of the hippocampus of an alzheimers patient, with the ca1 region magnified. Jun 05, 2015 focal epilepsy is often of temporal lobe origin but the true prevalence of tle is not known. Seizure freedom from temporal lobe epilepsy with mesial temporal lobe tumor by tumor removal alone without hippocampectomy despite remaining abnormal discharges on intraoperative electrocorticography. The epileptogenic region in mesial temporal lobe epilepsy mtle is known to extend beyond the hippocampus, to a network of cortical and subcortical structures, varying across patients. Mesial temporal lobe epilepsy with hippocampal sclerosis. In young individuals, mesial temporal sclerosis is commonly recognized with temporal lobe epilepsy tle. Mesial temporal lobe epilepsy texas childrens hospital. Both extracellular plaques and intracellular tangles are. Secondary generalisation is much less common than in extratemporal lobe epilepsy.
As the name implies, there are many different cognitive, affective, and psychomotor symptoms. Request pdf mesial temporal lobe epilepsy temporal lobe epilepsy tle is the most common form of adult localizationrelated epilepsy. The medial temporal lobe of the brain also known as the mesial temporal. In all patients with tle 117 patients, 100%, in the evolution of at least one seizure, abdominal auras were followed by oral and manual. Mar 07, 2012 temporal lobe epilepsy with mesial temporal sclerosis usually presents between 610 years of age but can present from infancy to the 30s. Unilateral mesial temporal lobe epilepsy how is unilateral. The current practice includes behavioural testing as well as mapping function via stimulation, inactivation, and more recently functional imaging. Defelipe j, fernandezgil ma, kastanauskaite a etal. Nourski md, phd 1, toshio moritani md 2, aristides a. The involvement of oxidative stress in the pathology of epilepsy has been largely examined using animal models, whereas studies on human tissues are scarce. Mesial temporal lobe epilepsy an overview of surgical. Temporal lobe epilepsy with mesial temporal sclerosis usually presents. The hallmarks of mesial temporal lobe epilepsy mtle are typical simple partial aura and complex partial with a loss of consciousness seizures, which can develop into secondary generalized tonicclonic seizures.
Typical unilateral mtle is associated with good outcomes after corticoamygdalohippocampectomy cah. Electroencephalography in mesial temporal lobe epilepsy. Allopregnanolone decreases interictal spiking and fast. Mesial temporal sclerosis is the most common lesion found in adults with temporal lobe epilepsy. A magnetic resonance imaging mri follow up study of children after febrile. If anything, care must be taken not to esclerosos an enlarged horn to trick you into thinking the hippocampus is reduced in size. The term temporal lobe epilepsy tle was included in the classification of the ilae in 1989 under the group of localization related symptomatic epilepsies characterized by seizures with sp e.
Mesialbasal temporal lobe epilepsy how is mesialbasal. Familial mesial temporal lobe epilepsy pdf paperity. Role of the temporal pole in temporal lobe epilepsy seizure networks. Temporal lobe epilepsy tle is the most common form of focal partial epilepsy. Lateralization of mesial temporal lobe epilepsy with chronic. Neurological and mental state usually normal prior to seizure onset. However, approximately 30% of all patients remain with persistent seizures after surgery.
The content on this site is presented in a summary fashion, and is intended to be used for educational and entertainment purposes only. Alzheimers disease, although it affects the entire brain, is particularly hard on the ca1 region. A resection of the mesial temporal lobe structures is a promising option in these cases. Mesial temporal lobe epilepsy is the most common type of focal epilepsy and in its course often becomes refractory to anticonvulsant pharmacotherapy. A focal seizure in the temporal lobe may spread to other areas in the. Background patients with mesial temporal lobe epilepsy tle often show bilateral temporal hypometabolism bth, but the nature of this finding has not been well established. Tle is most of all characterized by the repeated and unprovoked occurrence of epileptic seizures which take their origin in temporal lobe structures. Hippocampal onset accounts for at least 80% of all. Secondary generalisation is much less common than in extra temporal lobe epilepsy. Electroencephalography eeg has an important role in the diagnosis and classification of epilepsy. Mesial temporal sclerosis mts is the most common cause of medically refractory temporal lobe epilepsy tle. Mesial temporal sclerosis and epilepsy health science journals. Hippocampal antioxidative system in mesial temporal lobe.
Longitudinal and crosssectional analysis of atrophy in pharmacoresistant temporal lobe epilepsy. Role of the temporal pole in temporal lobe epilepsy seizure. It is known that some inherited epilepsies, such as myoclonic. Amnesia is the rule for the blank spell and the automatism. Few data concerning human epilepsy suggest that temporal lobe seizures had short. Temporal lobe epilepsy with mesial temporal sclerosis usually presents between 610 years of age but can present from infancy to the 30s. Seizure freedom from temporal lobe epilepsy with mesial. Mesial temporal lobe epilepsy mtle is the most common form of partial epilepsy in adults 1, and it is estimated that it represents about 40% of all epilepsies in this age range. The complete disconnection of the epileptogenic neural networks in the mesial temporal lobe determines the success of resective surgery. Mesial temporal lobe epilepsy mtle is a common form of human focal epilepsy, with hippocampal sclerosis a common underlying pathology 2. Unilateral mesial temporal lobe epilepsy listed as umtle. Mesial temporal sclerosis and temporal lobe epilepsy.
Temporal lobe epilepsy tle is the most common form of adult localizationrelated epilepsy. Hippocampal antioxidative system in mesial temporal lobe epilepsy. Temporal lobe epilepsy is a form of focal epilepsy, a chronic neurological condition characterized by recurrent seizures. Mesial temporal epilepsy, hippocampal sclerosis, glutathione peroxidase,mitochondria,superoxidedismutase,catalase. Clinical manifestations preexisting complex febrile convulsions are common. Capizzano md 2, patricia kirby md 3, hiroto kawasaki md 1, matthew howard iii md 1 and mary ann werz md 4. Although seizures in mtle heavily involve the temporal lobes, it is now clear that there are more anatomically widespread functional disturbances 3. Neuroimaging in temporal lobe epilepsy cns spectrums. Mesial temporal lobe epilepsy an overview of surgical techniques. The electroencephalogram eeg of mesial tle contains interictal features often associated with anterior temporal epileptiform discharges with a maximal voltage over the basal. In most patients, the epileptogenic focus involves the structures of the mesial temporal lobe illustrated in the diagrams below. This is a pdf file of an unedited manuscript that has been accepted for publication. Not only the memory, but even speech lateralization may be directly influenced by temporal lobe seizures.
Allopregnanolone decreases interictal spiking and fast ripples in an animal model of mesial temporal lobe epilepsy, neuropharmacology 2017, doi. Mts is usually a progressive disorder and seizures initially controlled with antiepileptic drugs can later become intractable in 6090% 16, 17. It can provide information for predicting the response to antiseizure drugs and to identify the surgically remediable epilepsies. It can be hard for people with tle to become completely seizure free with seizure medicines alone, though medicines may lower the number of seizures. In the 1950s, falconer stressed the importance of mesial temporal sclerosis mts in surgery for mesial temporal lobe epilepsy mtle. Mesial temporal lobe epilepsy with hippocampal sclerosis 2004. Simple focal seizures are the initial nonfebrile seizures followed by complex focal. He showed that patients with intractable epilepsy tended to have a better seizure outcome after standard anterior temporal lobectomy with amygdalohippocampectomy if mts was found pathologically falconer and.
Mesial temporal lobe epilepsy mtle is the most common form of partial. Complex partial seizures, as in psychomotor temporal lobe epilepsy, usually, but not always, originate in the temporal lobe of the brain, often with a preceding aura. Mesial temporal lobe epilepsy is the most common surgically treated epilepsy syndrome, with efficacy demonstrated in randomized controlled trials. For many years it has been held that these lesions may be related to complicated febrile convulsions in childhood but the association is based on retrospective data and a causeandeffect relationship has not been proved. Hermann et al 1 recently identified the neuropsychological features of the syndrome of mesial temporal lobe epilepsy mtle.
Tle is the most common form of epilepsy with focal seizures. Epileptic activity influences the speech organization in. Mtle is the most common type of epilepsy and is often characterized by the sense of an aura immediately preceding the seizure. Periodic epileptiform discharges in mesial temporal lobe. Mesial temporal lobe epilepsy mtle is a common epilepsy type and is usually resistant to antiepileptic drugs. Simple focal seizures are the initial nonfebrile seizures followed by. The seizure onset zone in mtle is hypothesized to be distributed among the hippocampus, amygdala, entorhinal cortex, and thalamus. Temporal lobe epilepsy caused by mesial temporal sclerosis and. Mesial temporal lobe mtl epilepsy is the most common surgically remediable form of epilepsy. The most common organic substrate for mtle is mesial temporal sclerosis mts. Extrahippocampal temporal lobe atrophy in temporal lobe. Early surgical intervention, when successful, might also prevent or reverse disabling.
Epilepsy arising in the medial temporal lobe mtle table 1 the commonest pathology underlying this type of epilepsy is hippocampal sclerosis3,4, and the entity of mesial temporal lobe epilepsy with hippocampal sclerosis mtle with hs is recognised as a distinctive constellation among the focal epilepsies5. Temporal lobe epilepsy definition of temporal lobe epilepsy. It can be sporadic, usually with positive family history, or it can present with clear familial recurrence 2. Mesialbasal temporal lobe epilepsy listed as mbtle. As a service to our customers we are providing this early version of the manuscript. Clinical, genetic, and mr characteristics of 68 patients with familial mesial temporal lobe epilepsy mtle were analysed at the university of campinasunicamp, brazil. Differential atrophy in mesial temporal structures. Prediction of postsurgical seizure outcome in left mesial.
1476 637 539 482 1259 1332 37 1236 385 521 31 1452 1500 1120 395 1512 6 442 104 1123 412 797 548 570 824 439 260 22 709 1404 534 1100 541 403 1480 1230 1191 1229 1474