Modeling and characterization of a valved glaucoma drainage device with implications for enhanced therapeutic efficacy

Tingrui Pan, Matthew S. Stay, Victor H. Barocas, J. David Brown, Babak Ziaie

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

We report on modeling and bench test results targeted at better understanding of valved glaucoma drainage devices (GDDs), a common current surgical treatment for glaucoma. A simple equivalent circuit is described to model fluid mechanical behavior of the aqueous humor in an eye with glaucoma, both before and after implantation of a valved GDD. Finite element method simulations (FEM), based on the lubrication-von Kármán model, are then performed to analyze the valve's mechanical and fluidic performance. Using nanoporous membranes to mimic the in vivo fibrous capsule, we have developed a microfluidic bench test to simulate the aqueous humor flow and the post-implantation fibrous tissue encapsulation around the GDD back plate. Our numerical and bench test results show that, contrary to the prevailing belief, the valve significantly contributes to the total pressure drop even after fibrous capsule formation. Furthermore, we show that bypassing the valve through a simple polyimide tube insertion will dramatically lower the intraocular pressure (IOP) after fibrous capsule formation. This may offer a new treatment option in some patients with advanced glaucoma.

Original languageEnglish (US)
Pages (from-to)948-951
Number of pages4
JournalIEEE Transactions on Biomedical Engineering
Volume52
Issue number5
DOIs
StatePublished - May 1 2005
Externally publishedYes

Fingerprint

Drainage
Fluidics
Encapsulation
Microfluidics
Polyimides
Equivalent circuits
Lubrication
Pressure drop
Tissue
Membranes
Finite element method
Fluids

Keywords

  • Ahmed Glaucoma Valve™
  • Glaucoma
  • Glaucoma drainage device
  • Microfluidic
  • Modeling

ASJC Scopus subject areas

  • Biomedical Engineering

Cite this

Modeling and characterization of a valved glaucoma drainage device with implications for enhanced therapeutic efficacy. / Pan, Tingrui; Stay, Matthew S.; Barocas, Victor H.; Brown, J. David; Ziaie, Babak.

In: IEEE Transactions on Biomedical Engineering, Vol. 52, No. 5, 01.05.2005, p. 948-951.

Research output: Contribution to journalArticle

Pan, Tingrui ; Stay, Matthew S. ; Barocas, Victor H. ; Brown, J. David ; Ziaie, Babak. / Modeling and characterization of a valved glaucoma drainage device with implications for enhanced therapeutic efficacy. In: IEEE Transactions on Biomedical Engineering. 2005 ; Vol. 52, No. 5. pp. 948-951.
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