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Abstract Maintaining the patency of indwelling drainage devices is critical in preventing further complications following an intraventricular hemorrhage (IVH) and other chronic disease management. Surgeons often use drainage devices to remove blood and cerebrospinal fluid but these catheters frequently become occluded with hematoma. Using an implantable magnetic microactuator, we created a self-clearing catheter that can generate large enough forces to break down obstructive blood clots by applying time-varying magnetic fields. In a blood-circulating model, our self-clearing catheters demonstrated a > 7x longer functionality than traditional catheters (211 vs. 27 min) and maintained a low pressure for longer periods (239 vs. 79 min). Using a porcine IVH model, the self-clearing catheters showed a greater survival rate than control catheters (86% vs. 0%) over the course of 6 weeks. The treated animals also had significantly smaller ventricle sizes 1 week after implantation compared to the control animals with traditional catheters. Our results suggest that these magnetic microactuator-embedded smart catheters can expedite the removal of blood from the ventricles and potentially improve the outcomes of critical patients suffering from often deadly IVH.
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Feasibility Studies on a Magnetic Swimmer for Wireless Hyperthermia Applications
Miniature Magnetic Rotating Swimmers (MMRSs) are emerging as a promising technology to improve minimally invasive vascular and cardiac surgeries. Currently, these procedures are typically performed using catheters, which are thin flexible tubes inserted into blood vessels. However, catheters rub against artery walls and can dislodge fat deposits, which can lead to complications such as stroke. In contrast, MMRSs are untethered, wirelessly controlled devices actuated by an external magnetic field. Their compact size could allow them to navigate the bloodstream of a patient and reach treatment areas without the risks associated with catheter use. Surgical tasks, such as tissue cutting or ablation, require significant power, but due to their miniature size, MMRSs lack the capacity to store sufficient onboard energy. This paper studies an MMRS that can be heated wirelessly via induction. The method allows transferring enough power to denature proteins.
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- PAR ID:
- 10665361
- Publisher / Repository:
- IEEE
- Date Published:
- Page Range / eLocation ID:
- 550 to 555
- Subject(s) / Keyword(s):
- robot, magnetic, medical, hyperthermia
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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