ReviewHippocampus, hippocampal sclerosis and epilepsy
Section snippets
Pathophysiology of epilepsy
Epilepsy is one of the most common neurological diseases and affects about 1% of the population [7]. An epileptic seizure is the result of functional disorders of the brain and is formed as a result of abnormal, excessive bioelectrical discharge in the nerve cells [21]. This disorder can theoretically occur in every population of neurons, but it is often observed in the immediate vicinity of organic brain damage, such as a scar or a tumor. A group of changed, overly excitable nerve cells is
Epileptogenesis
The process of epileptogenesis is usually explained in the literature by the two-hit hypothesis. The term epileptogenesis commonly refers to a period of time from the first hit, such as trauma or stroke, to the occurrence of the first epileptic seizure. It is a chronic process, in which a series of biochemical and structural changes take place in the nerve tissue. Experimental and clinical studies have shown that nerve tissue in experimental animals and in patients with epilepsy, although it
Anatomy of hippocampus
The hippocampus is an essential part of the archeocortex. In mammals, it is three-layered structure located on the medial surface of the temporal lobe in the back of each cerebral hemisphere. The name hippocampus is derived from Greek and means sea horse, which it resembles in shape. In the literature, it is often referred to as Ammon's horn (cornu Ammonis), which is derived from the distinctive image of an Egyptian god. The hippocampus is an important part of the limbic system, which plays
HS: cause or effect of epilepsy?
Despite the well-studied histological and ultrastructural basis of HS, its pathophysiology remains unclear. Whether HS is a primary cause of focal epilepsy or maybe the result of repeated epileptic seizures is still an unanswered question [47].
In generally accepted theory and aforementioned epileptogenesis two-hit hypothesis, the initial insult of even a small area of nerve tissue of the brain caused by various etiological factors leads to a stretched over time sequence of histological and
HS and antiepileptic drugs
HS is characterized by three pathological histological changes: loss of neurons, glial reaction (gliosis), and remodeling of neuronal networks especially interneurons (sprouting). Therefore, it is interesting to question whether and how antiepileptic drugs (AEDs) may prevent HS. AED mechanisms of action are mainly based on their effects on ion channels (sodium and calcium), excitatory and inhibitory amino acid receptors, inhibition of GABA metabolism and synaptic transmission [58]. All of these
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Cited by (61)
Is depression in patients with temporal lobe epilepsy related to hippocampal sclerosis? A meta-analysis
2023, Clinical Neurology and NeurosurgeryPsychiatric symptoms predict drug-resistant epilepsy in newly treated patients
2022, SeizureCitation Excerpt :Evidence indicates a relationship between the extent of hippocampal dysfunction with the severity of depression symptoms in epilepsy [43]. Hippocampal sclerosis has also been reported to be one of the major pathogenic factors of DRE [44]. Additionally, cognitive function in major depression disorders may be related to aberrant functional connectivity in cognitive networks, and patterns of alternate brain networks could influence cognitive processes [45].