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Abstract
More than 30% of epilepsy patients are not controlled by anti-epileptic medications. For patients having intractable epilepsy, epilepsy surgery is an effective treatment, which provides not only control of seizures but also improvement of quality of life. Epilepsy surgery can provide complete seizure control in over 60% of patients having medically intractable epilepsy. In order to identify surgical candidates, various diagnostic modalities are being used. The value of video-EEG monitoring and MR imaging study cannot be over-emphasized. For certain circumstances, other diagnostic modalities, such as PET, SPECT, and MEG, provide complementary data. If the findings from these non-invasive studies collectively indicate that the patient can benefit from surgery, surgical resection can be performed. However, if the findings do not, invasive studies should follow. New surgical modalities for the treatment for epilepsy have been developed, including surgical resection of epileptogenic zone or lesion, disconnection of epileptogenic zone from the surrounding normal brain, and neuromodulation, such as vagal nerve stimulation, deep brain stimulation, etc. Also, newly emerging diagnostic modalities, such as high tesla MR imaging, magnetoencephalography or brain mapping technology, can help select surgical candidates more easily in the near future.
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Figure 1.
Diagnosis and triage algorithm for surgical treatment of epilepsy at the Seoul National University Hospital.
Figure 2.
A) A 27-year-old male patient presents with chronic epilepsy. Preoperative T2-weighted axial image shows indistinct gray? white matter border in the left frontal lobe.
B) Preoperative 18?F?fluorodeoxyglucose positron?emission tomography (FDG?PET) shows decreased metabolism in the left frontal lobe.
C) Preoperative ictal single photon emission computed tomography (SPECT) shows increased perfusion in the left frontal lobe.
D) Preoperative magnetoencephalography (MEG) shows clustered interictal spkes in the left frontal lobe.
E) Invasive study had to be performed in order to delineate epileptogenic zone and adjacent language and motor cortex. Epileptogenic zone is in the left frontal lobe.
F) Postoperative T2?weighted axial image shows resection of the left frontal area. Postoperatively he becomes seizure?free.
Table 1.
Presurgical neuropsychological tests for epilepsy surgery at the Seoul National University Hospital.
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