In Vivo Measurement of Surface Pressures and Retraction Distances Applied on Abdominal Organs During Surgery

Abstract

Abstract:This study undertook the in vivo measurement of surface pressures applied by the fingers of the surgeon during typical representative retraction movements of key human They also form a basis for the design of next-generation organ retraction and space creation surgical devices with embedded sensors which can further quantify intraoperative retraction forces to reduce injury or trauma to organs and surrounding tissues.

Magnetic Anchoring Considerations for Retractors Supporting Manual and Robot-Assisted Minimally Invasive Surgery

“…The retraction already caused significant challenges due to its large size. Based on a 2018 study, it was determined that 11.25 N force is required to retract the liver [21]. Notable, this is already reaching the physical limits of the original da Vinci tools.…”

“…The fundamental idea of the magnetic solution was to design an insertable magnetic structure that can act as an internal anchor point for liver manipulation, so that the abdominal wall could remain intact during retraction. In this concept, the distance between the insertable magnetic structure and the external magnet would be equivalent to the abdominal wall thickness, over which sufficient magnetic force would need to be maintained so that the internal structure could hold the weight of the liver [21]. It should be noted that the wall thickness and physiological parameters vary from patient to patient, within a wide range.…”

Stability and Retraction Force Verification of a New Retractor Design for Minimally Invasive Surgery

“…Among the large abdominal organs, such as the liver, stomach and bowels, the liver was chosen since it covers and obstructs the largest workspace of abdominal procedures, and the retraction of which still causes significant challenges due to its large size. Based on a 2018 study it was determined that 11.25 N force is required to retract the liver [9]. The liver retraction solution therefore will focus on achieving sufficient lifting of the right or the left lobe of the liver where the former is necessary for cholecystectomy procedures where the Calot's triangle needs clear exposure [10] and the latter for bariatric procedures where the hiatus needs exposure [11].…”

“…The fundamental idea of the magnetic solution was to design an insertable magnetic structure that would act as inter- nal anchor points for liver retraction, so that the abdominal wall could remain intact during retraction. In this concept, the distance between the insertable magnetic structure and the external magnet would be equivalent to the abdominal wall thickness, over which sufficient magnetic force would need to be maintained so that the internal structure could support the weight of the liver [9]. This solution would consist of multiple internal rod magnets, each anchored externally by magnets positioned outside the human body.…”