Steerable Intravitreal Inserts for Drug Delivery: In Vitro and Ex Vivo Mobility Experiments

  • Christos Bergeles
  • Michael P. Kummer
  • Bradley E. Kratochvil
  • Carsten Framme
  • Bradley J. Nelson
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6891)


The progress of wet age-related macular degeneration can now be controlled by intravitreal drug injection. This approach requires repeated injections, which could be avoided by delivering the drug to the retina. Intraocular implants are a promising solution for drug delivery near the retina. Currently, their accurate placement is challenging, and they can only be removed after a vitrectomy. In this paper, we introduce an approach for minimally invasive retinal drug delivery using magnetic intraocular inserts. We briefly discuss the electromagnetic-control system for magnetic implants and then focus on evaluating their ability to move in the vitreous humor. The mobility of magnetic intraocular implants is estimated in vitro with synthesized vitreous humors, and ex vivo with experiments on cadaver porcine eyes. Preliminary results show that with such magnetic implants a vitrectomy can be avoided.


Hyaluronic Acid Vitreous Humor Drug Reservoir Electromagnetic Control Intravitreal Drug 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Christos Bergeles
    • 1
  • Michael P. Kummer
    • 1
  • Bradley E. Kratochvil
    • 1
  • Carsten Framme
    • 2
  • Bradley J. Nelson
    • 1
  1. 1.Institute of Robotics and Intelligent SystemsETH ZurichZurichSwitzerland
  2. 2.InselspitalUniversitätspital BernBernSwitzerland

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