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Siddiqui What is risk of pigmentary glaucoma from pigment dispersion syndrome?
gender distribution of the 1990 U.S. white population. For calculation of PDS incidence,
both PDS and pigmentary glaucoma patients were included, as all pigmentary glaucoma
patients have the findings of PDS. Only patients with glaucoma were included in the
incidence of pigmentary glaucoma, however. Incidence rates from studies of patients
seeking care should be considered minimum estimates, as it is likely that additional
patients with the condition exist, but were not included as they did not seek care.
Confidence intervals for incidence rates were calculated using Poisson distribution.
Results
A total of 136 patients were included in the study. 113 patients were diagnosed
with pigment dispersion syndrome over the 24-year interval from 1976 to 1999. An
additional 23 patients were found to have pigmentary glaucoma on initial examination
during this same interval. All patients were white. For comparison, the population of
Olmsted County in 1990 was 95% white, 3% Asian, and 0.72% black.
Pigment dispersion syndrome: probability of conversion to pigmentary glaucoma
1) Characteristics of PDS patients: The most common clinical sign present at
diagnosis of pigment dispersion syndrome was a Krukenberg spindle, found in 95% of
cases (107/113), undoubtedly because of its obvious presence at slit lamp examination.
Radial midperipheral iris transillumination defects were present in 86% (97/113), and
increased trabecular meshwork pigmentation in 86% of patients with records detailing the
amount of pigment seen with gonioscopy (48/56). The majority of patients (81%)
demonstrated both Krukenberg spindle and iris transillumination defects. Only 42%
(48/113) of patients had all three signs. Of note, 18% of patients had heavy pigmentation
