食道運動機能障害に対するPOEM—非アカラシアに対するLES温存の筋層切開（LES preserving myotomy）を中心に

Per-oral Endoscopic Myotomy for Motility Disorders in the Esophagus：Lower Esophageal Sphincter Preserving Myotomy for Non-Achalasia Patient

要旨●食道アカラシアに対するPOEMが誕生して15年以上が経過した．現在では，POEMは国内外ともアカラシアの標準治療となっている．症状スコアからみたPOEMの成功率は国際的にも95%を超える．double scope法で筋層切開の長さを厳密にコントロールしている本邦では，POEM後のGERDはほとんど問題となっていない．一方，アカラシア以外の食道運動機能障害（hypercontractile esophagus，distal esophageal spasm）は，LESの嚥下時の弛緩を確認したうえで，LES preserving myotomy（下部食道括約筋温存の筋層切開）が施行される．まれではあるが狭窄部を伴うIEMはPOEMの適応となり，狭窄部のないIEMはPOEM以外の治療法を模索することとなる．

　The development of per-oral endoscopic myotomy（POEM）as a treatment for esophageal achalasia was done more than 15 years ago. So far, POEM has been administered to more than 3,200 consecutive patients in our facility. POEM has provided treatment for over 6,000 patients in whole Japan. Recently, POEM has been accepted as the standard treatment course for achalasia at both national and international levels. Based on symptom scores, POEM achieved a success rate of more than 95% worldwide. In Japan, because the duration of myotomy is rigorously regulated with the use of the double scope method, post-POEM gastroesophageal reflux disease is rare. However, for esophageal motility disorders other than achalasia（such as hypercontractile esophagus and distal esophageal spasm）, LES（lower esophageal sphincter）preserving myotomy is performed following confirmation that the LES relaxes during swallowing. Although rare, IEM（ineffective esophageal motility）with stricture may be a reason for POEM, whereas IEM without stricture necessitates investigation of treatment options outside POEM.