Endoscopic Treatment of Esophageal Varices: Obara Method

  • Katsutoshi ObaraEmail author


Endoscopic treatment is the first choice for treating esophageal varices in Japan. In particular, the Obara method, which is known as the ethanolamine oleate (EO)-Aethoxysklerol (AS) combination method, is widely performed as it contributes to a low risk of recurrence. Inject 5% EO into all the esophageal varices and their feeding veins under fluoroscopy until they can be imaged on a fluoroscopy monitor. After the esophageal varices are obliterated using the EO method, inject 1% AS into the obliterated varices and their surrounding mucosa so that shedding of the obstructed esophageal varices and sclerosis of the esophageal wall by fibrosis can be expected. The Obara method is an extremely useful procedure for preventing recurrence by completely eradicating esophageal varices.


Esophageal varices Obara method EO-AS combination method Ethanolamine oleate Aethoxysklerol 


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© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.Department of Advanced Gastrointestinal EndoscopyFukushima Medical UniversityFukushimaJapan

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