June 2020
Volume 61, Issue 7
Free
ARVO Annual Meeting Abstract  |   June 2020
SIMULATION AND MODELING OF SACCADIC MOTION WITH SYNERESIS OF NANOPARTICLE SURROGATE DRUG DISPERSION
Author Affiliations & Notes
  • Anita Nikolova Penkova
    Mechanical Engineering Department, University of Southern California, Los Angeles, California, United States
    Radiology, Children's Hospital Los Angeles, Saban Research Center, Los Angeles, California, United States
  • Shuqi Zhang
    Mechanical Engineering Department, University of Southern California, Los Angeles, California, United States
  • Mark Humayun
    Department of Ophthalmology, USC Roski Eye Institute, Los Angeles, California, United States
    Department of Integrative Anatomical Sciences, University of Southern California, Los Angeles, California, United States
  • Satwindar Singh Sadhal
    Mechanical Engineering Department, University of Southern California, Los Angeles, California, United States
    Radiology, Children's Hospital Los Angeles, Saban Research Center, Los Angeles, California, United States
  • Footnotes
    Commercial Relationships   Anita Penkova, None; Shuqi Zhang, None; Mark Humayun, None; Satwindar Sadhal, None
  • Footnotes
    Support  NIH Grant 5R01EY026599
Investigative Ophthalmology & Visual Science June 2020, Vol.61, 21. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Anita Nikolova Penkova, Shuqi Zhang, Mark Humayun, Satwindar Singh Sadhal; SIMULATION AND MODELING OF SACCADIC MOTION WITH SYNERESIS OF NANOPARTICLE SURROGATE DRUG DISPERSION. Invest. Ophthalmol. Vis. Sci. 2020;61(7):21.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose : The primary purpose of this work is to measure the effect on drug distribution due to syneresis combined with saccadic motion in an aged eye by simulating the corresponding motion and liquefaction in a mechanical model.

Methods : A mechanical model using a motor controller was programmed to provide the motion equivalent to the sideways saccadic motion in human eyes. Based on preliminary experiments on ex vivo bovine eyes with mechanically liquefied pockets in the vitreous, it has been expected and observed that the effect of simulating eye motion on a deposited drug surrogate (Gd-DTPA) is much more significant within the liquefied regions than the intact gel regions. However, proper comparison of cases with and without saccadic motion are quite challenging because of difficulty in replicating the topography of the syneresis. Therefore, a simulation study using 3D-printed spherical liquid pockets was conducted. Density stratification within the liquid pocket results in relative motion due to inertial effects when saccadic oscillations take place, in addition to the gravitational effects. A spherical syneretic pocket is simulated as a 10 mm diameter saline-filled cavity off-center within a larger 38 mm sphere to represent the dimensions of a bovine eye.

Results : A 100-microliter solution of colored nanoparticles 80 nm in diameter (NanoCym) was injected in solution form into the saline-filled spherical cavity and photographic images were obtained for the progression of the nanoparticle dispersion both with and without the simulated saccadic motion. Since the particle density was slightly higher than the saline, a slow downward drift was observed. Without saccadic motion (control), diffusion took place and an equilibrium distribution (a balance of gravity and diffusion) was achieved in about 10 hours. With simulated saccadic motion, the mixing was enhanced and highly dispersed distribution was observed after 3 hours. Repeating the experiments two more times showed similar results.

Conclusions : The effect of saccadic motion on macromolecular and nanoparticulate drug distribution is not significant in the gel portion of the vitreous. However, within the liquid region, cases with and without the simulated saccadic motion have shown that such oscillatory motion enhances the distribution levels when the drug density is different from the liquid.

This is a 2020 ARVO Annual Meeting abstract.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×