Future Plans

A testing model including a jar filled with mock intestines and positioning for a model gallbladder will be created for bench top testing. This test jar will be covered with layers of plastic wrap to model the abdomen wall, and the device will be tested through an incision site. This provides for a less formal and less expensive testing model to make small changes that the group sees fit.

The SimPORTAL set up we used included a bucket containing "mock" intestines and a water balloon used to model the gallbladder. The bucket was covered by a porcine intestine wall and secured around the top rim of the bucket. Incisions in the abdomen wall were made and laparoscopic instruments were inserted. We'd like to repeat this with our newest prototype iteration, and potentially use ovine gallbladders from the University of Minnesota Experimental Surgical Services Lab to better replicate the true model.

Bag:

• For prototyping, we'd like to continue the use of Ripstop Nylon as that is the standard for these type of devices. However, we would be interested in a material that is thinner and has more flexible material properties.

• Since remodeling this bag is not a goal of this project, the material can be similar to that of previous devices.

Shaft:

• For the next iteration, we would like to continue use of PVC piping for the inner and outer shafts.

  • Prior to the cease of prototyping, we planned to use PVC piping that reduced the outer diameter of the device to 1.2cm, but this was not implemented.

• For future iterations, we would move toward biocompatible materials.

Funnel Frame:

• Continue developing with nitinol.

  • Nitinol wire of different diameters was ordered before prototyping was ceased due to COVID-19.

  • Prototyping and testing showed the material to be an appropriate choice when observing the ability of the nitinol to compress into the funnel when retracted while still adequately deploying to its original shape to the extent the collar allowed.

Suture Loop:

• The suture material seemed to have the desired strength but more testing needs to be done in order to confirm this.

• Other suture materials and sizes should be tested for comparison.

Sizing:

• One main design change that would be implemented in further iterations would be scaling down the size of the device. It needs to be able to fit within a 1 cm diameter incision site.

Collar/Funnel Design:

• We would like to make the collar thinner in order to allow the prongs of the nitinol wires to flare out more when deployed from the shaft. This would provide more flexibility than the prongs of the frame currently have, so that they can create a larger funnel base.

• We have currently implemented a collar design that does not allow for an opening at the top of the funnel where the gall bladder could be accessed if necessary. This is a design consideration we had planned to take into consideration with the next iteration of the device.

Ease of Use:

• Implement more device specs for ease of use for the surgeon. This would include color coding the handles to correspond with the order of use for each aspect, ensuring the handle design is comfortable during the entire length of the procedure, and further elements that would result from gathering input from surgeons.

After the third iteration prototype is completed, our plans (time permitting) included testing this new iteration once more.

As used for testing of the first generation prototype, the SimPORTAL system at the University of Minnesota would be used for device testing. Ideally, in this stage we would have had surgeons and medical students from the University of Minnesota aid in the testing of the device. This way, we would be able to gain more information about the ease of use of the device and what features they would like to see added to make the device more desirable over the competitor devices.

If we were able to continue on with this project and extend it outside of senior design, the hope would be that the device could be manufactured and potentially scaled up or down to apply to other surgeries and not only cholecystectomies.