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Updated: Jan 27, 2026

Experimental Glaucoma Induced by Ocular Injection of Magnetic Microspheres
Published on: February 2, 2015
Noninvasive monitoring of blood flow using a single magnetic microsphere
Maik Liebl1, Bernhard Gleich2, Dietmar Eberbeck3
1Physikalisch-Technische Bundesanstalt, Abbestraße 2-12, D-10587, Berlin, Germany. maik.liebl@ptb.de.
Abstract:
Noninvasive medical imaging of blood flow relies on mapping the transit of a contrast medium bolus injected intravenously. This has the draw-back that the front of the bolus widens until the tissue of interest is reached and quantitative flow parameters are not easy to obtain. Here, we introduce high resolution (millimeter/millisecond) 3D magnetic tracking of a single microsphere locally probing the flow while passing through a vessel. With this, we successfully localize and evaluate diameter constrictions in an arteria phantom after a single passage of a microsphere. We further demonstrate the potential for clinical application by tracking a microsphere smaller than a red blood cell.
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