著者
Takufumi YANAGISAWA Ryohei FUKUMA Ben SEYMOUR Koichi HOSOMI Haruhiko KISHIMA Takeshi SHIMIZU Hiroshi YOKOI Masayuki HIRATA Toshiki YOSHIMINE Yukiyasu KAMITANI Youichi SAITOH
出版者
The Japan Neurosurgical Society
雑誌
Neurologia medico-chirurgica (ISSN:04708105)
巻号頁・発行日
pp.st.2018-0099, (Released:2018-07-12)
参考文献数
41

A brachial plexus root avulsion (BPRA) causes intractable pain in the insensible affected hands. Such pain is partly due to phantom limb pain, which is neuropathic pain occurring after the amputation of a limb and partial or complete deafferentation. Previous studies suggested that the pain was attributable to maladaptive plasticity of the sensorimotor cortex. However, there is little evidence to demonstrate the causal links between the pain and the cortical representation, and how much cortical factors affect the pain. Here, we applied lesioning of the dorsal root entry zone (DREZotomy) and training with a brain–machine interface (BMI) based on real-time magnetoencephalography signals to reconstruct affected hand movements with a robotic hand. The DREZotomy successfully reduced the shooting pain after BPRA, but a part of the pain remained. The BMI training successfully induced some plastic changes in the sensorimotor representation of the phantom hand movements and helped control the remaining pain. When the patient tried to control the robotic hand by moving their phantom hand through association with the representation of the intact hand, this especially decreased the pain while decreasing the classification accuracy of the phantom hand movements. These results strongly suggested that pain after the BPRA was partly attributable to cortical representation of phantom hand movements and that the BMI training controlled the pain by inducing appropriate cortical reorganization. For the treatment of chronic pain, we need to know how to modulate the cortical representation by novel methods.
著者
Youichi SAITOH
出版者
社団法人 日本脳神経外科学会
雑誌
Neurologia medico-chirurgica (ISSN:04708105)
巻号頁・発行日
vol.52, no.7, pp.451-456, 2012 (Released:2012-07-25)
参考文献数
36
被引用文献数
1 2

The use of electrical motor cortex stimulation (EMCS) for post-stroke pain was established in Japan and has spread globally. EMCS has been used for the treatment of neuropathic pain, Parkinson's syndrome, and recovery of motor paresis. Since 2000, repetitive transcranial magnetic stimulation (rTMS) has been developed for the treatment of various neurological disorders. rTMS is a non-invasive method with almost no adverse effects. In the USA, rTMS of the left dorsolateral prefrontal cortex was approved for the treatment of major depression in 2008. rTMS of the primary motor cortex (M1) has been studied worldwide for the treatment of neuropathic pain, Parkinson's disease, motor paresis after stroke, and other neurological problems. New methods and devices for rTMS therapy are under development, and rTMS of the M1 is likely to be established as an effective therapy for some neurological disorders. The present review discusses EMCS and rTMS of the M1 concisely.
著者
MICHINORI KABUTO IKUO NAMURA YOUICHI SAITOH
出版者
The Japan Endocrine Society
雑誌
Endocrinologia Japonica (ISSN:00137219)
巻号頁・発行日
vol.33, no.3, pp.405-414, 1986 (Released:2011-01-25)
参考文献数
14
被引用文献数
35 40

Plasma melatonin levels were determined every 20 and 30min for 24 hours on the last day of repeated oral administrations (1 or 2mg a day for 8 or 9 days) of a benzodiazepine derivative (450191-s), which is known to be metabolized to active benzodiazepines after administration. In one of the two subjects, the nocturnal enhancement of plasma melatonin which was obvious on a control day with placebo was diminished almost completely. In the other subject, observed were not only the diminishment of its nocturnal enhancement but also its increase during the daytime almost to the nocturnal levels on a control day, which may indicate a rebound increase in melatonin synthesis or a shift in its day-night rhythmicity.Such suppressing effects of benzodiazepines on the nocturnal plasma melatonin levels were also examined in the case of a single administration of 2mg of 450191-s or flunitrazepam in the second series of experiments. Even a single flunitrazepam seemed to have lowered nocturnal plasma melatonin levels, which then recovered to the usual levels following the administration of 5mg of a benzodiazepine antagonist, Ro 15-1788, given 6 hours after the flunitrazepam. However, single 450191-s did not show any remarkable effects.Thus, it has been suggested that benzodiazepines could suppress the nocturnal levels of plasma melatonin or shift its day-night rhythmicity at least when administered repeatedly. The possible action site of benzodiazepines may be the central nervous system, since melatonin synthesis has been thought to be under strongly regulated by the central nervous pathway from the retina to the pineal body. Therefore, these effects of benzodiazepines may provide a method for investigating the physiological role of melatonin and its day-night rhythmicity as well as to further clarify the system regulating melatonin synthesis in humans.