Serotonergic PET in temporal lobe epilepsy

PET and selected ligands offer brain mapping for a panoply of neuronal receptors and other important brain molecules. Neurochemically specific PET studies have yielded numerous biomarkers of hippocampal and extrahippocampal dysfunction, which often have been used to study groups with temporal lobe epilepsy (TLE). Etiologies and the development of epilepsy are poorly understood in TLE, however. Further, causative pathophysiologies are largely unelucidated with regard to the variations in neuronal function that induce seizure onset at a particular point in time, or the persistence of the interictal state; the mechanisms underlying interictal disorders of cognition and mood in TLE are equally obscure. Perhaps as a result, neurochemically specific PET biomarkers have been less helpful in helping us understand epilepsy progression or other manifestations in individual patients with TLE, than in simply contrasting differences in interictal biomarkers between groups with and without TLE. An even more elusive goal has been development of etiology-specific PET maps that might guide precise diagnosis and effective therapy of the individual patient with TLE.