Improved Tools for Laparoscopic Surgery

Published: Dec 16, 2022 by Liz Metzger

(3D Printing, Solidworks, Molding)

For this project I worked in a group developing a laparoscopic suction irrigation handle that is more ergonomic and universal to decrease surgeon fatigue and improve device handling. I was responsible for the CAD modeling and manufacturing of our device and we all worked together to come up with a design that we all felt met our goals.

Our device focuses on making the handle of the laparoscopic tool an overall comfortable experience for the surgeon. To do this, we decided to make the handle resizable so that a surgeon could comfortably grip the device at whatever width fit them best. The client can do this by using a ratcheted scissor lift to increase the width of the device. Once the surgery is over, all the client has to do to return the device to its original form is slide the vertical bar from its locked position and press down fully. We also decided to add a smooth silicone material that would conform to the patient’s grip, creating a more comfortable experience overall. To help provide a neutral hand position we also added an adapter that can be added to a laparoscopic suction device where the metal tip normally attaches to change the angle the device works at.

To get to the final design we started by modeling our device out of recycled materials like clay and cardboard to get a rough idea of how our different mechanisms would interact. After we had a good idea of how we wanted the deice to function I fleshed out the design and CAD’ed an initial version that we printed out at 2X scale so that the pieces would be easier to work with. I CAD’ed between three and eight iterations for each of the different parts of our device. I ended up having to make a lot of changes to the designs so that they would actually be manufacturable with the resources we had, mainly 3D printing. the base of the device had to be printed in two halves that could be clicked together with a tight clearance fit so that all of the supports from printing could be removed and that the rods and ratchet could be assembled. I also ended up using a 3D printed mold to cast the silicone insert out of Smooth-On Ecoflex 00-20 Super Soft Silicone Rubber. You can see the base in the image below.

partial_laprascopic

One of the largest challenges of this project was that we were retrofitting an existing device so our attachment needed to be able to be fitted onto the bottom of the old device using these pegs that were not aligned in any reasonable manner or oriented relative to each other in a way that made sense. It was impossible to get measurements of the pegs to create CAD for our device so that we could attach the pieces with a tight clearance fit so I ended up taking a 3D scan of the original base of the device and using that 3D model to help me position the alignment holds on my design.

scanning_laprascopic

pegs_larprascopic

Below is a layout of all of the parts that I CAD’ed and printed.

part_laprascopic