Intern University of Pittsburgh Pittsburgh, Pennsylvania, United States
Introduction:: Over the course of 12 weeks, a design focused project was conducted within the University of Pittsburgh’s Makerspaces. The project focused on further developing, designing, and building a concept provided by an undergraduate student working with neurosurgeons. The undergraduate student observed the loss of endoscope visualization during sinus and skull-based tumor removal surgeries. During the surgery, debris such as blood and mucus accumulate on the lens, blocking the view. This requires the removal, cleaning, and reinsertion of the lens each time visualization is compromised. The undergraduate student proposed the concept of ScOAPe, a self-cleaning endoscope attachment that eliminates the need for manual cleaning of the lens. The project came with size and shape limitations, which meant the design must be no more than 6x6mm, cylindrical, and must not impede visualization from the distal end of the endoscope. The goal was to enable suction and irrigation in-situ when debris blocks endoscope view. Over the project’s timeline, several levels of ideation, sketching, prototyping, evaluation, and redesign occurred, proving the initial concept impractical, while leading to a different proof of concept. The new design is intended to be mass manufactured, affordable, and used for various endoscope models.
Materials and Methods:: The project unfolded over two stages. During the first stage, the initialScOAPe model was prototyped and tested. The model was 3-D printed at larger scales using PLA and resin. Both prints yielded unsuccessful low-resolution prototypes. The model was then printed to scale, leading to a successful high-resolution print. This model was tested on an endoscope, however, surface area constraints for water traveling along the attachment made adequate irrigation impractical during surgeries. This led to the second stage of the project: researching the needs of neurosurgeons and creating an attachment that would only irrigate. Ideation started with basic sketching, yielding two possible designs. Of these, the first design would require titanium machining which would be expensive, time consuming, and ultimately harder to manufacture, and thus the secondary design was chosen. Ideation led to rapid prototyping, which involved various sketches and CAD modeling. Due to the flexible nature of the chosen design, 3-D printed molds were created and dip-casted. Materials for the sheath were chosen based on flexibility, printing precision, manufacturability, and input from machining professionals. Finally, the sheath was installed on the endoscope using cyanoacrylate glue, followed by a round of testing with water. Specific information about these designs is protected under project IP rights.
Results, Conclusions, and Discussions:: The flexible design was chosen to fully finalize in future development, due to its affordability, application diversity, feasibility, mechanical strength, and its compatibility with various irrigation tubing. With adjustments to the molds, this design is compatible with various endoscope models, including ones of varying sizes as well as different lens tilt angles. Suction proved to be unnecessary for this project after discussion with neurosurgeons, since suction is currently achieved through existing tools during the surgery. Testing of the initial ScOAPe design has also been documented and taken into account for future development of self-cleaning endoscope attachments. Two main issues were noted for this design: the attachment compromised visualization, and the increase in surface area for water made it nearly impossible for the water to fully saturate the attachment with the given pressure limits.
Acknowledgements (Optional): : Rohit Mantenna, the undergraduate student who had the initialScOAPe concept for a self-cleaning endoscope attachment. Natasha Mody, Ritesh Shrivastav, Daniel Rieker, Ridwon Khaliq for their contribution and participation in the design and construction of these prototypes. Brandon Barber, Daniel Yates, Dr. William Clark for their guidance and mentorship during the course of the project.
