Original article| Volume 17, ISSUE 1, P147-152, January 2021

First prospective clinical trial of reduced incision bariatric procedures using magnetic liver retraction

Published:August 26, 2020DOI:


      • The magnetic surgical system provides a safe and effective alternative for liver retraction.
      • The system can be used in patients with wide range of body mass index (BMI).
      • The magnetic surgical system reduces the need of a dedicated port for liver retraction.



      Exposure of the surgical field is an essential component of minimally invasive surgery. Liver retraction is an important element of bariatric procedures because visualization of the stomach and gastroesophageal junction is key. The magnetic surgical system provides a well-tolerated and effective option for adjustable liver retraction without the use of a dedicated port.


      The purpose of this study was to evaluate the safety profile and effectiveness of the magnetic surgical system in patients undergoing bariatric procedures.


      Two investigational sites in Chile.


      A prospective, single-arm study ( NCT03508674) with adherence to Good Clinical Practices and ISO 14155:2011(E) was undertaken to evaluate the safety profile and effectiveness of the magnetic surgical system in patients undergoing bariatric surgery. Patient follow-up occurred at 7 and 30 days postprocedure.


      A total of 50 patients who met the inclusion criteria had a body mass index ranging from 28.4 to 58.2 kg/m2. All procedures were completed without complications or conversions. The average overall procedure time was 61 minutes, and the amount of coupling time between the magnetic controller and the detachable grasper was 37 minutes. In all cases the device was able to adequately retract the liver to achieve an effective exposure of the target tissue and perform the bariatric procedure. A total of 24 adverse effects were reported throughout the course of the study. All device-related adverse effects were mild in severity and resolved with no clinical sequelae.


      The magnetic surgical system is a well-tolerated and effective option for liver retraction in minimally invasive and bariatric surgery in patients with a varying range of body mass indexes.

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