Open Access
Buydash, Melissa Christine
Area of Honors:
Mechanical Engineering
Bachelor of Science
Document Type:
Thesis Supervisors:
  • Mary I Frecker, Thesis Supervisor
  • Zoubeida Ounaies, Honors Advisor
  • biopsy
  • endoscopy
NOTES (natural orifice transluminal endoscopic surgery), a technique conducted with an endoscope inserted through natural orifices, has the potential to completely revolutionize surgical procedures. The technique presents the unique possibility of incision-free (and thus scar-free) surgery. Though progress has been made in NOTES as a minimally invasive surgery (MIS) throughout the past few years, it has become increasingly apparent that several obstacles remain and need to be overcome before NOTES can become a preferred surgical technique. One such obstacle is that of limited instrumentation. The three objectives of this research will help to overcome this obstacle. The first objective was to develop a testing procedure for the Olympus EZ-Shot. With a testing protocol, better comparisons between developing needles and a readily available needle were able to be made. The second objective was to apply the testing procedure to benchmark a prototype 2-dimensional endoscopic biopsy needle against the Olympus EZ-Shot, and the third was to determine the effect of prototype needle thickness on removal force and mass removed. The results of this research showed that neither the 300 or 400 micrometer thickness needle performs better than the Olympus EZ-Shot in mass removed or removal force. However, the EZ-Shot removed a large amount of liquid mass in addition to solid mass, so the results may be skewed unfavorably for the prototype needle. The two needle thicknesses tested showed a correlation in which mass removed and removal force increase proportionally with increases in thickness. After measuring actual needle thicknesses, there was also an 84% linearly increasing relationship between actual needle thickness and mass removed. It would be interesting to see if these correlations continue over a larger needle thickness range. This research also showed that average friction force induced by the actuating handle of the EZ-Shot is 2.570 +/- 0.205 N. These results show that the prototype needle design is a viable one, but improvements need to be made to the testing procedure in order to obtain more conclusive results. The sample used contained a high moisture content which may have significantly altered test results, so a lower moisture sample is desired in future testing to limit mass removed to solid mass only. Additionally, “a scooping” design could be considered for prototype modification to increase mass removal.