Deep brain stimulation (DBS) is rapidly expanding the therapeutic domain of neurosurgery and has dramatically changed the landscape of neurosurgery. It has been speculated that DBS modulates local neuronal activity and influences regions associated with the dysfunctional anatomic circuits and structures that have been regarded as potential targets with reversibility. Overall, the technique consists of the delivery of current into a deep brain site such as the thalamus or basal ganglia through implanted electrodes. It is estimated that more than 80, 000 patients worldwide have received DBS, with the rate of accrual currently approaching 8, 000 to 10, 000 new patients per year. The appropriate operative indications for DBS is mainly movement disorders and intractable pain. Movement disorders, particularly, Parkinson disease, dystonia, and essential tremor, are frequently treated by DBS. Severe motor fluctuation and dopa-induced dyskinesia in Parkinson disease are successfully treated by subthalamic or pallidal stimulation. Dramatic improvement is often shown after the pallidal stimulation in patient with primary generalized dystonia. In addition, essential tremor is also expected to immediately improve after thalamic stimulation. On the other hand, recently, applications of DBS beyond movement disorders include the treatment of epilepsy and neuropsychiatric disorders.

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The neuron, unlike many other cells, has a limited capacity for self repair. For this reason, many trials to repair dopaminergic neurons by transplanting new cells have been conducted. Cell replacement therapy for Parkinson's disease (PD), however, has not been realized to date. In vivo gene transduction using viral vectors has become a promising strategy for delivering target genes to the brain; having overtaken ex vivo gene delivery techniques based on superiority in both widespread coverage of target area and long-term gene expression. Employing either a recombinant adeno-associated virus type 2 (AAV2) or a lentivirus vector, four different gene therapy approaches for PD have been tested in humans. In the first, the glutamic acid decarboxylase gene was transferred into the subthalamic nucleus, the currently preferred target for deep brain stimulation, in an attempt to restore normal physiological function of the basal ganglia circuitry. Safety of the AAV2 was confirmed in this phase I trial, and a randomized, blinded phase II trial is currently in progress. The second clinical trial is aimed at protecting the degenerating dopaminergic neurons by putaminal delivery of AAV2- neurturin, a growth factor similar to glial derived neurotrophic factor. Notable improvements were reported in patients in this phase I trial. Neurturin treatment failed, however, to meet the primary end point in a phase II trial because of a placebo effect. The last two approaches focus on increasing dopamine production via direct delivery of genes involved in dopamine synthesis : tyrosine hydroxylase, guanosine triphosphate cyclohydrolase 1, and amino acid decarboxy-lase (AADC). When these three genes are expressed in the putamen, dopamine can be synthesized automatically. Gene transfer of AADC alone in combination with oral levodopa would be a safer strategy. In the latter approach, the patients still need to take levodopa, but excess production of dopamine could be avoided by simply reducing the dose of levodopa. This phase I trial of putaminal injection of AAV2-AADC showed clinical and radiographical improvements in the treated PD patients. The optimal vehicle for delivery of three genes simultaneously into the putamen would be a vector capable of delivering all genes in the same particle. AAV2 is unsuitable in this regard due to its limited packaging capacity. Lentiviral vectors are better suited due to their larger packaging capacity. Recently, a clinical trial of injecting triple genes into the putamen has been started using a lentiviral vector derived from the equine infectious anemia virus.

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It is important and yet bothersome for physicians to treat neuropathic pain. Neuropathic pain can be caused by a number of different diseases (e.g., diabetes mellitus, herpes zoster, brachial plexus avulsion, complex regional pain syndrome (CRPS), failed back surgery syndrome (FBSS), spinal cord injury, post stroke central pain (CPSP), and multiple sclerosis). There are many medicines for neuropathic pain, however, pharmacological relief of neuropathic pain is often insufficient. In such cases, surgical intervention can be attempted. Ablative surgery procedures including thalamotomy and DREZtomy were formerly applied for patients with such intractable pain, while neuromodulation therapies including spinal cord stimulation (SCS), deep brain stimulation (DBS), motor cortex stimulation (MCS), peripheral nerve stimulation (PNS) and repetitive transcranial magnetic stimulation (rTMS) are used today. Spinal cord stimulation (SCS) is efficacious in FBSS and CRPS type I (level B recommendation). DBS could be efficacious in treating phantom pain, or brachial plexus avulsion. MCS is efficacious in CPSP and facial pain (level C). Evidence for implanted peripheral stimulation is inadequate. rTMS has transient efficacy in treating central and peripheral neuropathic pain (level B). Further controlled trials are warranted for SCS in conditions other than failed back surgery syndrome and CRPS and for MCS and DBS in general. These chronically implanted techniques provide satisfactory pain relief in many patients, including those resistant to medication or other means.

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Spasticity can cause significant problems with activity and participation for people with a variety of neurological disorders. It can also represent a major challenge to the rehabilitation team. However, modern approaches to management, making the best use of new drugs and new techniques can produce significant benefits for the disabled person. The details of these techniques are outlined in this report. The purpose of this report is to provide a general overview of spasticity management therapies, especially intrathecal baclofen (ITB), selective dorsal rhizotomy (SDR), and selective peripheral neurotomy (SPN). ITB is used in patients with widespread spasticity in whom alternative methods of spasticity management are ineffective or inadequate or cause unacceptable side effects. A trial dose of intrathecal baclofen is first administered to demonstrate that ITB will make a significant impact on the level of spasticity. After implantation surgery, pumps are refilled percutaneously by injection through the filling port every three months. Catheter or pump failure leads to a sudden withdrawal of medication, which can occasionally cause a serious withdrawal syndrome of high fever, hallucination, impaired consciousness, spasticity, and multiple organ failure. SDR is a surgical procedure to treat CP children by selectively cutting the dorsal rootlets from L2 to S1 based upon their responses to electrical stimulation. SDR has a long history of use worldwide and is a well-recognized treatment for children with spastic cerebral palsy. SDR has several variations that can be classified into two groups, wide laminectomy and limited laminotomy. Each technique has its advantages and disadvantages, but a number of publications have confirmed the efficacy of the various dorsal rhizotomy techniques. SPNs are indicated when spasticity is localized to the muscles or muscular groups supplied by a single or a few peripheral nerves that are easily accessible. The general rule is to tailor individual treatments as much as possible to the particular problems of the patient.

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There is no question regarding the importance of basic research for the development of neurosurgery. However, young neurosurgeons have difficulties in finding time for basic research in recent years. Experience in basic research is an important step to gain abilities indispensable for clinical activities as a neurosurgeon : the ability to actively make a research plan, the ability to think scientifically and logically, and the ability to solve problems, reading comprehension of English papers and the ability to proceed statistically. When performing basic research, an important attitude is to see not only the leaves (molecules) but also the trees (neurons) and the forest (brain); that is, not to forget feedback to clinics. One will feel great happiness when the result of basic research can be applied clinically as a translational research. In this article, the author will explain the significance of basic research in education for neurosurgeons and discuss about the improvement of research surroundings at the university and academic society level.

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The significance of a commitment to clinical research is discussed in the education of neurosurgeons in Japan. It is well known that clinical research and basic research are inseparably related these days. Translational research bridges both and indeed it plays a main paradigm role in practical research in contemporary medicine. Therefore, experience in an active commitment to clinical research is indispensable in the construction of a carrier path for clinical neurosurgeons. In this paper, the author introduces the comparative subsidence of the power of clinical and basic research in Japan from the perspective of the global standard and positioning in other Asian countries. In addition, the basic method to advance in clinical research is described. The practical structure to be learned and basic requiremens to be obtained including the laws and ethics in clinical research are shown. Finally, the significance of clinical research in the education of neurosurgeons is stressed from the team medicine viewpoint.

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The American Council for Graduate Medical Education (ACGME) sets the minimum standards for neurosurgery training in the United States. In recent years, these minimum standards have been revised and reorganized into clinical Core Competencies : Patient Care, Medical Knowledge, Practice-based Learning and Improvement, Professionalism, and System-based Practice. Though basic science or clinical research is not a requirement, the ACGME specifies a minimum standard of scholarly activity in neurosurgery training. At many institutions in the United States, and at Emory University in Atlanta, Georgia, a more formal program has been established to promote the academic development of neurosurgery residents. The goal is to encourage residents to pursue research and publication, teaching, and ultimately a goal in the university setting. Like many institutions, Emory University requires residents to participate in research. At the very beginning of their training, we introduce first-year residents to a committee of research mentors that guide the residents into research laboratories or into clinical research as they mature in the training program. In the middle years of training, residents are required to publish papers (case reports, retrospective studies, prospective studies), and incentives are created to stimulate this activity such as attending national and international meetings. Research efforts are organized by sub-specialization, and specific projects and sources of funding are prepared in advance of the each resident's research year. Near completion of the neurosurgery training, guidance and support is given to residents desiring an academic position. This includes instruction in applying for young investigator grant support as well as help in identifying job opportunities. The specific aspects of the Emory program in neurosurgery academic development are reviewed in this paper.

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We report a case and characteristic findings for optic nerve hemangioblastomas, which are extremely rare. Preoperative diagnosis of the optic nerve tumors is difficult. A 33-year-old man with left blindness for 12 years, was accidentally found to have an intracranial tumor. Magnetic resonance imaging (MRI) showed a 2.6cm well-enhancing mass, which involved the left prechiasmal optic nerve and extended into the optic canal with swollen bilateral postchiasmal optic nerves. Cerebral angiography showed a hypervascular tumor supplied by the left ophthalmic artery. We successfully removed the tumor after embolizing the left ophthalmic artery using micro-coils. Histological examination revealed a typical hemangioblastoma, although the patient had no clinical findings and no familial histories of von Hippel-Lindau disease. Postoperative MRI showed reduce swelling in the bilateral postchiasmal optic nerves.

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