الفهرس 
Gross anatomyOnly 14 pages are availabe for public view
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Abstract
Epilepsy is a chronic disease that affects about 1% of world population. Virtually any disturbance in brain tissue may cause seizures. The distribution of these seizures depends on the affected part of the brain.
Epilepsy affects about 50 million people in the world, about 30% of those individuals suffer from persistent seizures and they don’t respond to medical treatment, so that the surgical interference is the treatment of choice.
Temporal lobe epilepsy is the most common type of epilepsy and often don’t respond to medical treatment and needs surgery.
Structural and functional neuroimaging plays an important role in the identification of the precise cortical region responsible for seizures and is very crucial for a good surgical outcome.
Advances in MRI have changed the workup of epilepsy dramatically. The role of radiologists was previously limited to ruling out gross pathology, such as occupying lesions, as the cause of seizures. Structural epileptogenic abnormalities can now be detected, localized, and differentiated on MRI, and a proper preoperative evaluation performed.
Advances in MRI include magnetic resonance spectroscopy and diffusion tensor imaging which has the unique propriety to provide chemical-pathological characterization of MR visible lesions and normal appearing brain tissues. So it is a sensitive tool for epilepsy lateralization and may indicate bilateral disease when conventional MRI is normal or shows unilateral pathology.
Diffusion tensor imaging (DTI) is also an advanced MRI technique which can indirectly evaluate the structural integrity of brain tissue by measuring water diffusion and its directionality in three dimensions. DTI has the potential to localize subtle epileptogenic lesions not seen on conventional MRI. In addition, information on the structural properties of brain tissue, provided by DTI, may give important insights into the pathophysiology of epilepsy and the acute and chronic effects of seizures on the brain. Tractography is a technique based on DTI data that visualizes white matter tracts in vivo, information that may be used to avoid surgical injury to functionally important white matter tracts.