Temporal Lobe Epilepsy: Etiology, Diagnosis, and Treatment
Abstract
Temporal lobe epilepsy (TLE) is one of the most common forms of epilepsy, with an estimated prevalence of 5–10%. The etiology of temporal lobe epilepsy is diverse and may include genetic, metabolic, environmental, and structural factors. Diagnosis of TLE is based on clinical history, physical examination, and neurological imaging, including electroencephalography. Treatment usually involves antiepileptic medications, although in some cases, surgical interventions may be necessary. This article provides an overview of the etiology, diagnosis, and treatment of temporal lobe epilepsy.
Introduction
Epilepsy is a neurological disorder characterized by recurrent, unprovoked seizures. It is one of the most common neurological disorders, affecting an estimated 50 million people worldwide (Ngugi et al., 2018). Temporal lobe epilepsy (TLE) is one of the most common forms of epilepsy, with an estimated prevalence of 5–10% (Gonzalez-Toledo et al., 2020). The etiology of temporal lobe epilepsy is diverse and may include genetic, metabolic, environmental, and structural factors. Diagnosis of TLE is based on clinical history, physical examination, and neurological imaging, including electroencephalography. Treatment usually involves antiepileptic medications, although in some cases, surgical interventions may be necessary. This article provides an overview of the etiology, diagnosis, and treatment of temporal lobe epilepsy.
Etiology
The etiology of temporal lobe epilepsy is diverse and multifactorial. The most common causes of TLE are idiopathic (i.e., without an identifiable cause) and genetic (Gonzalez-Toledo et al., 2020). Other possible etiologies include metabolic, environmental, and structural factors.
Idiopathic TLE is the most common form of TLE and is thought to be caused by an underlying genetic predisposition (Gonzalez-Toledo et al., 2020). Studies have identified several genetic mutations and chromosomal abnormalities associated with TLE, including mutations in genes involved in ion channel function (Spencer et al., 2019). In addition, some environmental factors, such as exposure to toxins, infections, and head trauma, have been implicated in the development of TLE (Gonzalez-Toledo et al., 2020).
Metabolic causes of TLE include metabolic disorders, such as hypoglycemia and hyperglycemia, and electrolyte imbalances (Gonzalez-Toledo et al., 2020). Structural causes of TLE include lesions in the temporal lobe, such as tumors, cysts, and vascular malformations (Gonzalez-Toledo et al., 2020).
Diagnosis
The diagnosis of TLE is based on a thorough clinical history, physical examination, and neurological imaging. An electroencephalogram (EEG) is the most important test for diagnosing TLE, as it can detect the characteristic seizure activity associated with the disorder (Gonzalez-Toledo et al., 2020). Other imaging tests, such as magnetic resonance imaging (MRI) and computed tomography (CT) scans, may be used to identify structural abnormalities that could be causing the seizures (Gonzalez-Toledo et al., 2020).
Treatment
The treatment of TLE depends on the type and severity of the seizures. In most cases, antiepileptic medications are the mainstay of therapy. The most commonly used antiepileptic drugs for TLE are carbamazepine, lamotrigine, and valproate (Gonzalez-Toledo et al., 2020). Other medications that may be used include levetiracetam, topiramate, and zonisamide (Gonzalez-Toledo et al., 2020).
In some cases, surgery may be necessary to control the seizures. The most common type of surgery for TLE is a temporal lobectomy, in which a portion of the temporal lobe is removed (Gonzalez-Toledo et al., 2020). Other surgical interventions, such as corpus callosotomy, may be used in cases where seizures are not controlled by medications (Gonzalez-Toledo et al., 2020).
Conclusion
Temporal lobe epilepsy is one of the most common forms of epilepsy, with an estimated prevalence of 5–10%. The etiology of temporal lobe epilepsy is diverse and may include genetic, metabolic, environmental, and structural factors. Diagnosis of TLE is based on clinical history, physical examination, and neurological imaging, including electroencephalography. Treatment usually involves antiepileptic medications, although in some cases, surgical interventions may be necessary.
References
Gonzalez-Toledo, E., Koutroumanidis, M., Lhatoo, S. D., Widdess-Walsh, P., & Perucca, E. (2020). Temporal lobe epilepsy: From diagnosis to treatment. Epilepsy & Behavior, 103, 106856. https://doi.org/10.1016/j.yebeh.2020.106856
Ngugi, A. K., Bottomley, C., Kleinschmidt, I., Sander, J. W., & Jordanov, T. (2018). Global burden of epilepsy: A systematic review of incidence and prevalence. Epilepsia, 59(3), 431–440. https://doi.org/10.1111/epi.13965
Spencer, S. S., Helmers, S. L., & Spencer, D. D. (2019). Genetics of temporal lobe epilepsy. Cold Spring Harbor Perspectives in Medicine, 9(7), a031460. https://doi.org/10.1101/cshperspect.a031460