The third edition of the International Classification of Headache Disorders (ICHD-3) was issued in January 2018, 30 years after the first edition of the ICHD was issued by the Headache Classification Committee of the International Headache Society, chaired by Jes Olesen. Formerly, the vascular theory was implicated in the pathophysiology of migraine, which was followed by the neuronal and currently the trigemino-vascular theory. The social understanding of headache has deepened in recent years. Patients with headache, who visit medical centers/hospitals wish to primarily exclude organic diseases, such as brain tumor or hemorrhage as a cause of their headache and also seek an accurate diagnosis of headache, together with an understanding of the pathology and measures to mitigate this distressing symptom. In this section, we focus on the characteristics and pathophysiology of migraine and cluster headache, which represent types of primary headaches that are associated with significant disability. Furthermore, we discuss novel treatments for headache using sophisticated device therapies and anti-calcitonin gene-related peptide antibody treatment.

  Benign paroxysmal positional vertigo (BPPV) is the most common cause of vertigo, with a lifetime prevalence of 2.4%. Vertigo/dizziness observed in patients with BPPV is attributed to debris that comprises small calcium crystals, which get displaced from the utricle and are lodged on the crista ampullaris and/or remain floating in the ear canal. BPPV is usually a self-limited condition ; symptoms subside or resolve approximately 1 month after onset in cases of posterior semicircular canal-type BPPV and within 2 weeks in cases of horizontal semicircular canal-type BPPV. Usually, a range of physical maneuvers and exercises, including the Epley and Lempert maneuvers can effectively treat BPPV. However, some patients with BPPV experience intractable, recurrent, and/or persistent symptoms. Presumably, otolith function deteriorates with age ; therefore, the number of patients with intractable BPPV continues to increase owing to rapid population ageing worldwide.

  Currently, the focus of research and therapy for Alzheimer's disease (AD) is shifting from the conventional neurotransmitter approach to the pathological and biochemical (pathogenic protein) approach aimed at disease-modifying therapy. Basic and clinical research is being performed to investigate the role of anti-amyloid strategies for AD based on the amyloid hypothesis. Owing to their toxic effects, insoluble amyloid β-protein (Aβ) fibrils, which accumulate as amyloid in the brain, were previously implicated in the pathogenesis of AD ; however, recent studies focus on the role of oligomers, which are more toxic aggregates of Aβ. Research is ongoing to develop anti-Aβ antibodies that target Aβ aggregates. Early- or preclinical stage administration of these agents is likely to be widely accepted in the near future for the management of patients with AD.

  Neurosurgeons comprise 20% of the members of the Japan Epilepsy Society and play a significant role in the diagnosis and treatment of adult epilepsy in Japan. We describe advances in the understanding and management of epilepsy in clinical practice.

  The potential role of genetic and autoimmune mechanisms as etiopathogenetic contributors to epilepsy has generated much interest among researchers. A recent genome-wide association study that included approximately 15,000 patients with epilepsy and approximately 30,000 controls identified 16 genome-wide significant loci and 21 candidate genes in these loci. The identified common genetic variants explain 32% and 9% of the liability to generalized and focal epilepsies, respectively.

  The discovery of an increasing number of neural autoantibodies in patients with epilepsy implicates autoimmunity as a likely mechanism underlying the etiology of this condition ; recent studies show that immunotherapy is more effective than antiepileptic medications to control seizures. Moreover, most patients do not develop chronic epilepsy after immunotherapy. A subset of patients with autoimmune epilepsy, particularly the type associated with leucine-rich glioma-inactivated 1 (LGI1) antibody encephalitis, present with drug-resistant seizures unaccompanied by major cognitive or behavioral symptoms, which are often misdiagnosed. Anti-LGI1 encephalitis is characterized by faciobrachial dystonic seizures.

  Large-scale real-world data have established the efficacy and safety of new antiepileptic drugs (AEDs). The registry of pregnant women who received antiepileptic monotherapy showed that the risk of major congenital malformations was significantly lower in children whose mothers received new AEDs than in children whose mothers received older AEDs. Notably, the new drugs showed similar effectiveness in seizure control during pregnancy.

  Less invasive approaches are increasingly being used in epilepsy surgery. Magnetic resonance-guided laser interstitial thermal therapy has emerged as a promising alternative to surgical treatment of mesial temporal lobe epilepsy. Responsive neurostimulation is used as adjunctive therapy for non-resectable focal epilepsies. Stereoelectroencephalography is gaining popularity for intracranial electroencephalography since the introduction of robot-assisted stereotactic electrode implantation. However, currently, the aforementioned less invasive modalities (except for the robotic system) are unavailable in Japan. The introduction of less invasive approaches potentially expands the surgical indications for epilepsy treatment.

  In summary, ongoing research is unraveling the diverse etiologies of epilepsy. Therefore, based on the underlying pathophysiology, a variety of treatment options are available to enable individualized therapy for epilepsy.

  In this article, we discuss the history, current status, and features of brain dock practice in Japan. The brain dock system was introduced in Japan in 1988 and plays an important role in the field of preventive medicine. Based on a survey to determine the current status of brain dock evaluations performed in Japan, initiated by the Japan Neurosurgical Society, neurosurgeons are closely involved in brain dock practice. The first edition of the guidelines for brain dock application was published in 1997, and these guidelines are revised every 5 to 6 years. The aims of brain dock evaluation outlined in the revised fifth edition (2019) of the guidelines describe not only prevention of stroke but also prevention of cognitive impairment. Functional imaging and functional tests are recommended in addition to existing morphological imaging. Brain dock practice is entering a new era in Japan.

  Patients with newly diagnosed glioblastoma (GBM) who show a Karnofsky Performance Scale (KPS) of 60-30 after initial treatment are unable to spend an independent life at home. In this study, we investigated the role of intensive rehabilitation of these patients aimed at improvement in KPS scores to 60 or 70 to facilitate their return to their homes. This study included 16 patients with GBM, who completed postsurgical radiotherapy combined with temozolomide (TMZ) administration. All patients underwent evaluation every 10 days from commencement to the end of rehabilitation, based on the Functional Independence Measure (FIM) scores. The rehabilitation program consisted of a daily regimen of individualized 180-min treatment sessions, 7 days a week, for 4-6 consecutive weeks.

  We observed improved FIM scores in 13 of 16 patients (81%) ; 7 patients (44%) acquired independent living ability (KPS 70) and 6 (37%) showed up to KPS score 60 (occasional assistance required from family). The time to maximal improvement after admission was within 20-50 days in these 13 patients and within 30 days (nearly 4 weeks) in 10 patients (77%). Short-term intensive rehabilitation (4-6 weeks) is effective in patients with GBM during the TMZ withdrawal phase after postoperative radiotherapy.

  Myxoid glioneuronal tumors carrying p.K385-mutant PDGFRA represent a novel central nervous system tumor type that originates from the septum pellucidum or lateral ventricle, and harbors a PDGFRA activating mutation. As it is a newly proposed tumor type, only a few related reports have been published, and there is no consensus concerning optimal treatment or prognosis. We treated a patient with myxoid glioneuronal tumor-harboring PDGFRA p.K385 mutant-occurring in the septum pellucidum. Gross total resection was performed, and the patient remained recurrence-free without further treatments as of the last follow-up.