Visceral organs present unique challenges to studying functional physiology and neural control. Visceral organs are often surrounded by a nerve plexus that provides distributed innervation along the organ surface and contain autonomic ganglia that can modulate function locally. Given this complexity, creating functional maps of visceral organ innervation is challenging. Another challenge is measuring organ state itself. This is significantly exacerbated by the fact that many of these organs are soft, elastic, and undergo large volume changes. In this proposal, we will develop soft silicone electrode nets compatible with these unique challenges and that can envelop visceral organs and deploy high-resolution electrodes to arbitrary positions on the organ surface. This approach is based on a 3D printed silicone electrode technology. These electrode nets will be augmented with strain gauge sensors and electrical impedance tomography electrodes to monitor physiological organ state. Ultimately, this new class of devices will 1) be intrinsically soft and elastic to allow conformation with visceral organs that undergo large volume changes, 2) integrate organ state sensors based on strain gauges and electrical impedance tomography, 3) prevent delamination issues typically associated with other thin film electrode manufacturing processes, and 4) allow rapid customization to cost-effectively transition to any organ system in animals or humans. This technology is based on materials that have a history of use in biomedical implants and are therefore potentially suitable for conducting neural mapping and electrophysiological studies of human organs in vivo. We will evaluate device performance using the bladder and urethra as a model due to the challenging interface requirements (e.g. large volume changes) and potential clinical relevance. Overactive bladder and urinary incontinence affects millions of people worldwide, is associated with costs upwards of $60 billion each year in the United States, and leads to significant decreases in quality of life. Electrode nets will be tested in acute cat experiments where we will determine the electrode-tissue mechanical stability, evaluate embedded sensor performance, and develop functional neural maps of the surface of the bladder and urethra. We will also validate device performance in a series of chronic animal experiments where device performance will be monitored for up to four months post-implant. An important feature of this enabling technology and associated manufacturing process is that these devices will be able to be quickly and cost-effectively redesigned to study other visceral organ systems including the stomach, intestines, and colon across a range of animal models as well as humans.

Public Health Relevance

Bioelectronic medicine initiatives are seeking to understand how neuromodulation of the peripheral nervous system could be used to improve human health through basic anatomical and physiological studies, yet in many cases these efforts are hampered by the lack of suitable tools to interface with the nervous system and visceral organs. We propose to develop soft silicone electrode nets that can envelop visceral organs that may undergo large volume changes and can be used to develop high-resolution functional maps of organ innervation while also monitoring the state of the organ itself. Performance of these electrode nets will be validated in the lower urinary tract in acute and chronic animal models.

Agency
National Institute of Health (NIH)
Institute
Office of The Director, National Institutes of Health (OD)
Project #
1OT2OD025297-01
Application #
9513136
Study Section
Next Generation Tools and Technologies (NGTT)
Program Officer
Qashu, Felicia M
Project Start
2017-09-15
Project End
2020-08-31
Budget Start
2017-09-15
Budget End
2018-08-31
Support Year
1
Fiscal Year
2017
Total Cost
Indirect Cost
Name
University of Pittsburgh
Department
Physical Medicine & Rehab
Type
Schools of Medicine
DUNS #
004514360
City
Pittsburgh
State
PA
Country
United States
Zip Code
15213