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Updated: Jun 9, 2026
05:22
Iris Fixation via External Pentagram Suturing
Published on: May 5, 2022
The concave iris in pigment dispersion syndrome
Lance Liu1, Ee Lin Ong, Jonathan Crowston
1Glaucoma Unit, Royal Victorian Eye and Ear Hospital, Victoria, Australia. drlsliu@hotmail.com
Ophthalmology
|August 31, 2010
Summary
Iris contour changes in pigment dispersion syndrome (PDS) were visualized. Fixation flattens the iris, blinking does not restore concavity, and accommodation induces it, suggesting accommodation maintains PDS iris curvature.
Area of Science:
- Ophthalmology
- Anterior Segment Imaging
- Iris Biomechanics
Background:
- Pigment dispersion syndrome (PDS) is characterized by iris abnormalities.
- Understanding iris dynamics in PDS is crucial for managing associated complications like glaucoma.
Purpose of the Study:
- To visualize iris contour changes in PDS patients.
- To assess the impact of blinking, accommodation, and pharmacologic miosis on iris configuration using anterior segment optical coherence tomography (AS-OCT).
Main Methods:
- Observational case series of 33 eyes from 20 PDS patients.
- AS-OCT (Visante) imaging along the 0- to 180-degree meridian.
- Scans performed at baseline and after fixation, blinking, accommodation, and pilocarpine-induced miosis.
Main Results:
- Iris became planar after 5 minutes of fixation (curvature decreased from 214 ± 74 μm to 67 ± 76 μm, P < 0.05).
- Iris remained planar after blinking; concavity did not significantly recover with -3.0 or -6.0 diopter lenses.
- Pilocarpine-induced miosis resulted in a planar iris configuration in all subjects.
Conclusions:
- The iris in PDS assumes a planar configuration during fixation.
- Iris concavity is not restored by blinking in PDS patients.
- Accommodation appears to induce and maintain iris concavity in PDS, suggesting a role in its pathogenesis.
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