Epilepsy surgery in Korea began as early as in the 1940s and continued to develop through the second half of the 20th century. Introduction of neuroimaging modalities, establishment of epilepsy monitoring units and the epilepsy team approach contributed to the rapid development. �or about 300�- 400 operations carried out yearly��, t�here i��s at �prese�nt suffi���cien�t n�umb ��er of ep�ileps� y surg�ery cen�ters�� an�d q�ualifi��ed neurosurgeons in Korea. However, Korean neurosurgeons should adapt themselves to changing recent trends. Etiologies of epilepsy have dramatically changed from head trauma and infectious diseases to tumors and developmental abnormalities. Although traditional resective surgery still constitutes the main bulk of the operations, new therapeutic procedures based on neuro�modulation are emerging as alternative treatments. There should also be participation in basic science research which would leads to future innovations in treatment of epilepsy.

The perioperative use of anticonvulsants in patients receiving craniotomy for various CNS diseases has been a routine practice in neurosurgery. However, there have been no unified evidence-based guidelines for the perioperative use of anticonvulsants. We searched for published studies related to this subject in MEDLINE and reviewed them. Several randomized controlled studies were regarded as more important because they could provide strong evidence. The conclusions are as follows. First, postoperative seizures are serious problems in neurosurgical practice and should be strictly controlled. Second, anticonvulsants could decrease the occurrence of postoperative seizures. Third, the therapeutic serum levels of anticonvulsants are of utmost importance in the prevention of postoperative seizures. Fourth, valproic acid has no advantage over phenytoin in the prevention of postoperative seizures.
Anticonvulsants* ; Central Nervous System Diseases ; Craniotomy ; Humans ; Neurosurgery* ; Phenytoin ; Seizures ; Valproic Acid

Epilepsy associated with brain tumors (EABT) is a multi-faceted disease that both oncological and epileptological concerns should be taken into consideration. Usually, it is characterized by chronic drug-resistant epilepsy with a low-grade brain tumor in the cerebrum. However, the distinction of typical EABT and simple brain tumors with short-term epilepsy is obscure. We need a working formulation based on the patient's burden in both oncological and epileptological aspects. The diagnosis of EABT is straightforward, but the treatment should be more complex. Medical treatment with anticonvulsants aloneseems tobe anoutdated remedy for EABT because of the risk of tumor growth and malignant progression in some patients as well as the expected favorable seizure control after surgery. Surgical treatment of EABT has resulted in seizure-free state in about 80% of patients. Complete resection of the tumor is an important prognostic factor in seizure control and probably also in tumor control. Recently, many authors emphasized a lesion-directed surgery aimed at a complete tumor removal in EABT. However, in some patients, especially in patients with dual pathology, electrophysiological studies have to be thoroughly applied. For the treatment of EABT in the temporal lobe, more sophisticated surgical strategy is required. A lesionectomy saving the uninterrupted hippocampus could be applied for selected patients. Further research is strongly needed for better understanding and treatment of EABT and low-grade glioma.
Anticonvulsants ; Brain ; Brain Neoplasms ; Cerebrum ; Epilepsy ; Glioma ; Hippocampus ; Humans ; Seizures ; Temporal Lobe

Epilepsy has been known to humankind since antiquity. The surgical treatment of epilepsy began in the early days of neurosurgery and has developed greatly. Many surgical procedures have stood the test of time. However, clinicians treating epilepsy patients are now witnessing a huge tide of change. In 2017, the classification system for seizure and epilepsy types was revised nearly 36 years after the previous scheme was released. The actual difference between these systems may not be large, but there have been many conceptual changes, and clinicians must bid farewell to old terminology. Paradigms in drug discovery are changing, and novel antiseizure drugs have been introduced for clinical use. In particular, drugs that target genetic changes harbor greater therapeutic potential than previous screening-based compounds. The concept of focal epilepsy has been challenged, and now epilepsy is regarded as a network disorder. With this novel concept, stereotactic electroencephalography (SEEG) is becoming increasingly popular for the evaluation of dysfunctioning neuronal networks. Minimally invasive ablative therapies using SEEG electrodes and neuromodulatory therapies such as deep brain stimulation and vagus nerve stimulation are widely applied to remedy dysfunctional epilepsy networks. The use of responsive neurostimulation is currently off-label in children with intractable epilepsy.
Child ; Classification ; Deep Brain Stimulation ; Drug Discovery ; Drug Resistant Epilepsy ; Electrodes ; Electroencephalography ; Epilepsies, Partial ; Epilepsy ; Humans ; Neurons ; Neurosurgery ; Seizures ; Vagus Nerve Stimulation

Epilepsy is one of the major chronic neurological diseases affecting many patients. Resection surgery is the most effective therapy for medically intractable epilepsy, but it is not feasible in all patients. Vagus nerve stimulation (VNS) is an adjunctive neuromodulation therapy that was approved in 1997 for the alleviation of seizures; however, efforts to control epilepsy by stimulating the vagus nerve have been studied for over 100 years. Although its exact mechanism is still under investigation, VNS is thought to affect various brain areas. Hence, VNS has a wide indication for various intractable epileptic syndromes and epilepsy-related comorbidities. Moreover, recent studies have shown anti-inflammatory effects of VNS, and the indication is expanding beyond epilepsy to rheumatoid arthritis, chronic headaches, and depression. VNS yields a more than 50% reduction in seizures in approximately 60% of recipients, with an increase in reduction rates as the follow-up duration increases. The complication rate of VNS is 3–6%, and infection is the most important complication to consider. However, revision surgery was reported to be feasible and safe with appropriate measures. Recently, noninvasive VNS (nVNS) has been introduced, which can be performed transcutaneously without implantation surgery. Although more clinical trials are being conducted, nVNS can reduce the risk of infection and subsequent device failure. In conclusion, VNS has been demonstrated to be beneficial and effective in the treatment of epilepsy and various diseases, and more development is expected in the future.
Arthritis, Rheumatoid ; Brain ; Comorbidity ; Depression ; Drug Resistant Epilepsy ; Epilepsy ; Equipment Failure ; Follow-Up Studies ; Headache Disorders ; Humans ; Seizures ; Transcutaneous Electric Nerve Stimulation ; Vagus Nerve Stimulation ; Vagus Nerve

Brain tumors are the second most common type of structural brain lesion that causes chronic epilepsy. Patients with low-grade brain tumors often experience chronic drug-resistant epilepsy starting in childhood, which led to the concept of long-term epilepsy-associated tumors (LEATs). Dysembryoplastic neuroepithelial tumor and ganglioglioma are representative LEATs and are characterized by young age of onset, frequent temporal lobe location, benign tumor biology, and chronic epilepsy. Although highly relevant in clinical epileptology, the concept of LEATs has been criticized in the neuro-oncology field. Recent genomic and molecular studies have challenged traditional views on LEATs and low-grade gliomas. Molecular studies have revealed that low-grade gliomas can largely be divided into three groups : LEATs, pediatric-type diffuse low-grade glioma (DLGG; astrocytoma and oligodendroglioma), and adult-type DLGG. There is substantial overlap between conventional LEATs and pediatric-type DLGG in regard to clinical features, histology, and molecular characteristics. LEATs and pediatric-type DLGG are characterized by mutations in BRAF, FGFR1, and MYB/MYBL1, which converge on the RAS-RAF-MAPK pathway. Gene (mutation)-centered classification of epilepsy-associated tumors could provide new insight into these heterogeneous and diverse neoplasms and may lead to novel molecular targeted therapies for epilepsy in the near future.
Age of Onset ; Astrocytoma ; Biology ; Brain ; Brain Neoplasms ; Classification ; Epilepsy ; Ganglioglioma ; Glioma ; Humans ; Molecular Targeted Therapy ; Neoplasms, Neuroepithelial ; Seizures ; Temporal Lobe

Sacrococcygeal teratoma (SCT) is an extragonadal germ cell tumor (GCT) that develops in the fetal and neonatal periods. SCT is a type I GCT in which only teratoma and yolk sac tumors arise from extragonadal sites. SCT is the most common type I GCT and is believed to originate through epigenetic reprogramming of early primordial germ cells migrating from the yolk sac to the gonadal ridges. Fetal SCT diagnosed in utero presents many obstetrical problems. For high-risk fetuses, fetal interventions (devascularization and debulking) are under development. Most patients with SCT are operated on after birth. Complete surgical resection is the key for tumor control, and the anatomical location of the tumor determines the surgical approaches. Incomplete resection and malignant histology are risk factors for recurrence. Approximately 10–15% of patients have a tumor recurrence, which is frequently of malignant histology. Long-term surveillance with monitoring of serum alpha fetoprotein and magnetic resonance imaging is required. Survivors of SCT may suffer anorectal, urological, and sexual sequelae later in their life, and comprehensive evaluation and care are required.

Sacrococcygeal teratoma (SCT) is an extragonadal germ cell tumor (GCT) that develops in the fetal and neonatal periods. SCT is a type I GCT in which only teratoma and yolk sac tumors arise from extragonadal sites. SCT is the most common type I GCT and is believed to originate through epigenetic reprogramming of early primordial germ cells migrating from the yolk sac to the gonadal ridges. Fetal SCT diagnosed in utero presents many obstetrical problems. For high-risk fetuses, fetal interventions (devascularization and debulking) are under development. Most patients with SCT are operated on after birth. Complete surgical resection is the key for tumor control, and the anatomical location of the tumor determines the surgical approaches. Incomplete resection and malignant histology are risk factors for recurrence. Approximately 10–15% of patients have a tumor recurrence, which is frequently of malignant histology. Long-term surveillance with monitoring of serum alpha fetoprotein and magnetic resonance imaging is required. Survivors of SCT may suffer anorectal, urological, and sexual sequelae later in their life, and comprehensive evaluation and care are required.

Dysembryoplastic neuroepithelial tumor (DNET) is a distinct type of low-grade glioneuronal tumor. Clinically, DNET is highly associated with intractable epilepsy in young children and adolescents. Therefore, the burden of the tumor comprises oncological concerns (recurrence), seizure control, and quality of life. The pathology of DNET is characterized by glioneuronal elements and floating neurons. Grossly, many DNETs harbor separate nodules on the medial side of the mass. Some of the satellite lesions are bone fide tumor nodules that grow during the follow-up. Therefore, removing all satellite lesions may be important to prevent tumor progression. Seizure control is highly dependent on the complete removal of tumors, and the presence of satellite lesions also exerts a negative impact on seizure outcomes.

The majority of clinical studies on moyamoya disease (MMD) have focused on anterior circulation. The disease involvement of posterior circulation in MMD, mainly in the posterior cerebral artery (PCA), has been mentioned since the early 1980s, and it has been repeatedly emphasized as one of the most important factors related to poor prognosis in MMD. However, its clinical features and outcome have only been elucidated during the last few years. In this review, the angiographic definition of PCA stenosis is summarized. The clinical features are elucidated as being either early-onset or delayed-onset, according to the time of PCA stenosis diagnosis in reference to the anterior circulation revascularization surgeries. The surgical strategy and hypothesis on the mechanism of PCA stenosis is also briefly mentioned. It appears that some MMD patients may show PCA stenosis during the early or late course of the disease and that the presenting symptoms may vary. Because the hemodynamic compromise caused by PCA stenosis may respond well to surgical treatment, clinicians should be aware of the condition, especially during follow-up of MMD patients.
Constriction, Pathologic ; Diagnosis ; Follow-Up Studies ; Hemodynamics ; Humans ; Moyamoya Disease* ; Passive Cutaneous Anaphylaxis ; Posterior Cerebral Artery* ; Prognosis