Increased iris-lens contact following spontaneous blinking: Mathematical modeling

Rouzbeh Amini, Sara Jouzdani, Victor H Barocas

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

The purpose of this work was to study in silico how iris root rotation due to spontaneous blinking alters the iris contour. An axisymmetric finite-element model of the anterior segment was developed that included changes in the iris contour and the aqueous humor flow. The model geometry was based on average values of ocular dimensions. Blinking was modeled by rotating the iris root posteriorly and returning it back to the anterior. Simulations with maximum rotations of 2°, 4°, 6°, and 8° were performed. The iris-lens contact distance and the pressure difference between the posterior and anterior chambers were calculated. When the peak iris root rotation was 2°, the maximum iris-lens contact increased gradually from 0.28 to 0.34. mm within eight blinks. When the iris root was rotated by 6° and 8°, the pressure difference between the posterior and anterior chambers dropped from a positive value (1.23. Pa) to negative values (-0.86 and -1.93. Pa) indicating the presence of reverse pupillary block. Apparent iris-lens contact increased with steady blinking, and the increase became more pronounced as posterior rotation increased. We conclude that repeated iris root rotation caused by blinking could maintain the iris in a posterior position under normal circumstances, which would then lead to the clinically observed anterior drift of the iris when blinking is prevented.

Original languageEnglish (US)
Pages (from-to)2293-2296
Number of pages4
JournalJournal of Biomechanics
Volume45
Issue number13
DOIs
StatePublished - Aug 31 2012

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Contact lenses
Blinking
Contact Lenses
Iris
Anterior Chamber
Geometry
Pressure
Aqueous Humor
Computer Simulation

Keywords

  • Anterior chamber angle
  • Aqueous humor
  • Eye
  • Finite element
  • Glaucoma
  • Pupillary block

Cite this

Increased iris-lens contact following spontaneous blinking : Mathematical modeling. / Amini, Rouzbeh; Jouzdani, Sara; Barocas, Victor H.

In: Journal of Biomechanics, Vol. 45, No. 13, 31.08.2012, p. 2293-2296.

Research output: Contribution to journalArticle

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