振戦に対する定位的外科治療

Stereotactic Surgery for Tremor

Point

・本態性振戦に対する定位的外科治療法として，脳深部刺激療法，高周波視床凝固術，集束超音波視床破壊術，ガンマナイフ視床凝固術が利用できる．

・破壊術，刺激術ともに視床中間腹側核（Vim核）が標的核であるが，刺激術ではposterior subthalamic area（PSA）も有力な標的核となる．

・刺激術はRCTの結果より凝固術と比べ効果・安全性に優れると考えられるが，近年，凝固術の技術的な進歩がみられる．

　Although tremor is one of the most common movement disorders, there are many different types, and proper diagnosis is important for appropriate treatment. Action tremor has a significant impact on daily life, but the effectiveness of medical treatment is insufficient, and surgery is often the treatment of choice. Surgical treatment is effective in suppressing tremor, and a large percentage of tremors can be adequately controlled. Currently available surgical treatments for tremor include the ventral intermediate nucleus of thalamus-deep brain stimulation（DBS）, radiofrequency（RF）-thalamotomy, focused ultrasound（FUS）-thalamotomy, and gamma knife thalamotomy. DBS is often considered the first choice for surgical treatment due to the number of past cases in which DBS has been applied, reported evidence, long-term efficacy, safety, adjustability, and the possibility of bilateral treatment, but RF-thalamotomy is also expected to improve efficacy and safety because of recent advancements in coagulation technology and the accumulation of anatomical knowledge regarding the target nucleus. In addition, the number of cases in which FUS-thalamotomy has been applied has been increasing in the past few years due to its minimally invasive nature, which does not require puncture of the brain. As neurosurgeons, we have the responsibility to select and perform appropriate surgical treatment based on sufficient knowledge of tremor to yield beneficial results in patients.