Design of a Compliant Endoscopic Suturing Instrument

2007 ◽  
Author(s):  
James A. Cronin ◽  
Mary Frecker ◽  
Abraham Mathew
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Compliant Mechanisms ◽  
Stress Relief ◽  
Initial Study ◽  
Response Patterns ◽  
Natural Orifice ◽  
Endoscopic Suturing ◽  
Jaw Opening ◽  
Puncture Force

This paper outlines the development and initial optimization of a compliant endoscopic suturing instrument. The developing field of Natural Orifice Transluminal Endoscopic Surgery requires innovative instruments to meet the size limitations inherent in this type of minimally invasive surgery; using compliant mechanisms is proposed as one method of meeting this requirement. Three initial compliant designs were created, modeled, and compared for a distal opening of 10 mm. Restricting these designs so that they must fit within a 3.3 mm working channel is currently unique in endoscopic suturing instruments. A design that utilizes contact for stress relief and intertwining parts for added deflection was selected from the three. ANSYS® was used to aid in graphical optimization to maximize the jaw opening and maximize the puncture force of the selected design. The best geometry has a distal opening of 13.8 mm at the tips and can supply a puncturing force of 6.33 N. A prototype has been machined using the optimized dimensions and is ready to be tested. This initial study in compliant suturing instrument designs has revealed response patterns for the chosen geometries that will lead to further refinements and improvements in future models.

Design of a Compliant Endoscopic Suturing Instrument

2008 ◽  
Vol 2 (2) ◽  
Author(s):  
James A. Cronin ◽  
Mary I. Frecker ◽  
Abraham Mathew
Keyword(s):  
Finite Element Analysis ◽  
Minimally Invasive Surgery ◽  
Compliant Mechanisms ◽  
Stress Relief ◽  
Natural Orifice ◽  
Endoscopic Suturing ◽  
Element Analysis ◽  
Design And Optimization ◽  
Puncture Force ◽  
Nonlinear Deformations

This paper describes the initial design and optimization of a compliant endoscopic suturing instrument. The emerging field of Natural Orifice Transluminal Endoscopic Surgery (NOTES) requires innovative instruments to meet the size limitations inherent in this type of minimally invasive surgery; using compliant mechanisms is proposed as one method of meeting this requirement. The compliant design was modeled and optimized to maximize the distal opening and provide a puncture force of at least 4.6N, while being small enough to fit within a 3.3mm working channel. The design utilizes contact for stress relief and intertwining parts for added deflection. ANSYS® was used for finite element analysis including contact and nonlinear deformations. A prototype was fabricated from the optimized geometry and experimentally tested. The best geometry is predicted to have a distal opening of 14.6mm at the tips and supply a puncturing force of 4.83N. The force supplied at the tip was measured and was found to exceed the required 4.6N. The prototype successfully passed two complete sutures and qualitative results are provided. The results of the study will lead to further refinements and improvements in future designs.

Design of a Multifunctional Compliant Instrument for Minimally Invasive Surgery

2005 ◽  
Vol 127 (6) ◽  
pp. 990-993 ◽  
Author(s):  
Mary I. Frecker ◽  
Katherine M. Powell ◽  
Randy Haluck
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Compliant Mechanism ◽  
Tissue Injury ◽  
Optimized Design ◽  
Jaw Opening ◽  
Multifunctional Device ◽  
Grasping Force ◽  
Length Width

A new multifunctional compliant instrument has been designed for use in minimally invasive surgery. The instrument combines scissors and forceps into a single multifunctional device. The main advantage of using multifunctional instruments for minimally invasive surgery is that instrument exchanges can be reduced, thus reducing procedure time and risk of inadvertent tissue injury during instrument exchanges. In this paper, the length, width, and thickness of the multifunctional compliant mechanism tool tip is optimized to maximize the jaw opening and the grasping force. The optimized design is then modeled to simulate the stresses encountered in the scissors mode. A 5.0mm diameter stainless steel prototype is fabricated using electro-discharge machining and is shown to grasp and cut successfully.

scholarly journals A Concealed “Natural Orifice”: Umbilicus Anatomy for Minimally Invasive Surgery

2018 ◽  
Vol 26 (1) ◽  
pp. 46-49 ◽  
Author(s):  
Mitsuhiro Asakuma ◽  
Koji Komeda ◽  
Masashi Yamamoto ◽  
Tetsunosuke Shimizu ◽  
Ryo Iida ◽  
...  
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Medical Curriculum ◽  
Abdominal Cavity ◽  
Fatty Tissue ◽  
Natural Orifice ◽  
True Nature ◽  
Umbilical Incision ◽  
Single Port Surgery

Introduction. A recent development in minimally invasive surgery (MIS) is single-port surgery, where a single large multiport trocar is placed in the umbilicus. All medical schools require that students complete an anatomy course as part of the medical curriculum. However, there is limited instruction regarding the detailed parts of the “umbilicus.” In several famous anatomy atlases, the umbilicus is not dissected at all and is merely represented as a button. Until now, the true nature of the umbilicus has not been anatomically demonstrated. Methods. Five cadavers were obtained from the Osaka Medical College medical student anatomy class. The umbilicus was dissected in the anatomy laboratory, to demonstrate all the layers. A detailed dissection was performed, focusing on the exact center of the umbilicus, in order to ascertain whether there exists a “natural orifice” or a fascial defect. Results. In all cadavers, a small defect of fascia was identified just below the center of the umbilicus. Yellow fatty tissue was present just below the skin in the exact center of the umbilicus. A probe placed exactly in the middle of this defect passes easily through into the abdominal cavity. Conclusions. With the widespread use of MIS, umbilical incision is commonly used to reduce pain and improve cosmetic results. This study consistently revealed a natural defect of fascia in the center of the umbilicus. Therefore, the umbilicus can be called a concealed “natural orifice.” It is important to recognize and utilize this defect effectively to minimize unnecessary tissue trauma during MIS.

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