The worldwide incidence of strokes is increasing and is now the leading cause of physical disability in adults [1]. Ischemic strokes are caused by blood clots in the blood vessels of the brain that cut off circulation. This causes a brain infarction and permanent brain damage [2]. Approximately 70% of all strokes are ischemic [3]. Fast treatment is very important in the case of acute strokes as it is directly related to the outcome of the treatment. To improve the outcome of stroke treatments, this research aims to design untethered magnetic robots (UMR) that can quickly move towards a blood clot and destroy it. To achieve this, the UMR needs to be controlled by a permanent magnet in an operating room. Real-time tracking is necessary to safely control the UMR through the blood vessels.
The operating room contains a CT arm that can provide images at an angle that can be used for real-time tracking. However, controlling a UMR in complex, structured blood vessels using 2D imaging poses several challenges. These challenges are pulsating flow, varying flow in blood vessels, and only having a 2D image as feedback. In my research, I will be taking the following steps. The first step to take would be to counteract the blood flow and being able to keep the UMR steady in a pulsating flow. Next, the challenge of different flows arises, as the diameter of the blood vessel changes, so does the flow; the UMR controller will need to be able to compensate for this. Finally, this needs to be combined to perform accurate 3D path following to the blood clot using only the images from the CT arm for real-time tracking. For the experiments, I will be using and adjusting the experimental setup that is already present.
[1] Stephen J. X.. Murphy and David J. Werring. “Stroke: causes and clinical features”. In: Medicine 48.9 (Sept. 2020), pp. 561–566. issn: 1357-3039. doi: 10.1016/j.mpmed.2020.06.002.
[2] Yang Yang et al. “New role of silent information regulator 1 in cerebral ischemia”. In: Neurobiol. Aging 34.12 (Dec. 2013), pp. 2879–2888. issn: 0197-4580. doi: 10.1016/j.neurobiolaging.2013.06.008.
[3] Michael S. Phipps and Carolyn A. Cronin. “Management of acute ischemic stroke”. In: BMJ 368 (Feb. 2020), p. l6983. issn: 1756-1833. doi: 10.1136/bmj.l6983.