Audible frequency vibration of puncture-access medical devices.

Ultrasonic vibration has been proven to help scalpels and puncture devices cut and cauterize, but creates a damaged tissue zone that may not be desirable. We have found that audible frequency vibration applied to a needle not only reduces puncture force more than ultrasonic vibration; it does not cause significant immediate tissue damage. Here we thus present a method for decreasing the force required to insert a puncture-access medical device and an analytical model for predicting performance of a hypodermic needle, which correlates well with tests and shows that needle insertion force is lowered not only by decreasing the outer diameter of the needle, but also by driving the device at its free state resonant (amplitude-maximizing) frequency. Finally, an in vivo histology study is conducted and suggests that audible frequency vibration results in the same degree of immediate local tissue damage as simple manually inserted needles, but that it causes significantly less immediate local tissue damage than ultrasonic vibration.

Classroom to Clinic: Merging Education and Research to Efficiently Prototype Medical Devices.

Innovation in patient care requires both clinical and technical skills, and this paper presents the methods and outcomes of a nine-year, clinical-academic collaboration to develop and evaluate new medical device technologies, while teaching mechanical engineering. Together, over the course of a single semester, seniors, graduate students, and clinicians conceive, design, build, and test proof-of-concept prototypes. Projects initiated in the course have generated intellectual property and peer-reviewed publications, stimulated further research, furthered student and clinician careers, and resulted in technology licenses and start-up ventures.