• endoscopic surgery;
  • gasless;
  • MIES;
  • minimum incision;
  • single port;
  • urological organs


Minimum incision endoscopic surgery (MIES) is a gasless, single-port access, cost-effective, and minimally invasive surgery that has been in development since the late 1990s. Use of MIES has steadily increased in Japan and Asia and has been introduced into Europe and the USA. In 2006, MIES was certified by the Japanese government as an advanced surgery and since 2008 it has been covered by the Japanese universal health insurance system as a new surgical technique. Briefly, MIES involves an initial minimum incision (a single port) that permits extraction of the target specimen. A wide working space through the port is then made by separating the anatomical plane extraperitoneally. This is maintained with special retractors instead of gas insufflation. All instruments including an endoscope are inserted through the port and the operation is completed. The size of the port can be tailored to the situation if necessary, which contributes to preclusion of patient selection. The procedure uses only two disposable devices that are inexpensive, resulting in low equipment costs. Surgeons have the benefits of magnified vision through endoscopy as well as stereovision and panoramic vision of naked eyes through the port, which reduces the technical demands of the procedure. Techniques for two basic MIES procedures allow MIES to be performed for most urological organs and in extraordinary cases by their modifications. Thus, the MIES system permits minimally invasive surgery without use of CO2 gas, which is ideal from medical, environmental and economic perspectives, is cost-effective and minimizes patient selection.