NOTES suction grasper for tubular viscera - characterization of gripping force when varying hole size, diameter, and number

This paper details the design and characterization of a novel suction grasper for Natural Orifice Transesophageal Surgery (NOTES). Axial gripping force was optimized by changing hole size, number, and spacing. A 10 kg pig and a rabbit esophagus were used to simulate a neonatal esophagus. Maximum axial forces of up to 7.2 N were achieved. Hole pattern spacing had little to no impact on force while suction area was very significant. Additionally, there was a preference for a greater number of holes versus larger holes for relatively large hole sizes. Lastly, smaller holes resulted in smoother loss of gripping force when beyond maximum holding force was applied.