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Siddiqui What is risk of pigmentary glaucoma from pigment dispersion syndrome?
intraocular pressure 21 or higher, glaucomatous optic nerve damage (increased cupping
or abnormal disc appearance), and glaucomatous visual field defects. Other types of
glaucoma (e.g., primary open angle glaucoma, exfoliative glaucoma, neovascular
glaucoma) were excluded. Therapy included topical anti-glaucoma medications, laser
trabeculoplasty, or filtering surgery. Cases of PDS and pigmentary glaucoma were
usually bilateral, but were also included if unilateral (n=12 cases).
The cumulative probability for conversion of pigment dispersion syndrome to
pigmentary glaucoma was estimated using the Kaplan-Meier method. Risk factors were
assessed using the Cox proportional hazards models. For patients converting to
glaucoma, the eye with the highest IOP was used in the analysis.
The long-term outcome of pigmentary glaucoma was assessed by noting visual
field progression using an eight stage field grading system, ranging from normal to
double arcuate scotomas.
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Progression was determined by changes in stage from the first
field to the most recent examination. Visual acuity loss from glaucoma, and any
requirement for laser or surgical intervention for glaucoma were recorded. Other causes
for visual loss were excluded, such as cataract or macular degeneration. Risk factors
studied were age, refractive error, intraocular pressure, family history of glaucoma, and
race. Intraocular pressure from the eye with the highest reading was used in calculation of
mean pressures and in risk factor analysis.
Estimation of annual incidence: The annual incidence rate was determined for
each 10-year age interval by dividing the number of newly diagnosed cases by the
Olmsted County population. Population data for Olmsted County, Minnesota were taken
from the United States census. These incidence data were then adjusted to the age and
