Neuroimaging of epilepsy.
It can sometimes be difficult, when examining surgical specimens, to detect underlying pathological abnormalities that may account for disordered electrical activity. For accurate diagnosis, neuropathologists and clinicians need to share common preoperative information about resected brain tissue. Our group has been able to use structural, functional, and electrophysiological neuroimaging techniques to visualize epileptogenic areas preoperatively. MRI is the most sensitive and useful examination to demonstrate structural abnormalities in patients with partial or localization-related epilepsy. Temporal lobe epilepsy, neoplastic lesions, vascular lesions, and developmental anomaly can all be surgically corrected under favorable circumstances. Functional neuroimaging by positron emission tomography (PET) and single-photon emission computed tomography (SPECT) are useful tools for detecting epileptic foci. PET and SPECT demonstrate subtle functional changes related to epilepsy that ultimately may enable the detection of epileptogenic areas invisible to MRI. PET/SPECT images coregistered to MRI and statistical parametric mappings are of more value for detecting than PET/SPECT images alone. Electrophysiological neuroimaging with analytical software is very useful for visually understanding epileptogenic phenomena. Computerized voltage topographic mappings overlapped on three-dimensional MRI with multichannel electrodes visually demonstrate ictal onset areas and seizure propagation. A new method of multimodal image-guided intervention enables the detection of epileptogenic areas by electrocorticography, PET images, and MRI during epilepsy surgery. Neuropathologists using this method can collect precise structural, functional, and electrophysiological findings on surgical specimens. Neuroimaging of epilepsy is useful for visually clarifying structural, functional, and electrophysiological information on epilepsy patients. This approach is key for diagnosing the background pathological abnormalities of resected tissue.
Maehara
Taketoshi
T
Neurosurgery, Department of Brain Medical Science, Tokyo Medical and Dental University, Tokyo, Japan. maehara.nsrg@tmd.ac.jp
D001921:Brain / Q000473:pathology*; D004827:Epilepsy / Q000473:pathology*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D049268:Positron-Emission Tomography; D015899:Tomography, Emission-Computed, Single-Photon