Cause of Pigment Dispersion Syndrome - Full Text View

Sponsored by:	National Eye Institute (NEI)
Information provided by:	National Institutes of Health Clinical Center (CC)
ClinicalTrials.gov Identifier:	NCT00005919

Purpose

The purpose of this study is to learn how pigment is released from the iris (the colored part of the eye) in patients with pigment dispersion syndrome.

It will do this by examining the response of the pupil (the central opening of the iris) to a flash of light to determine what is happening in the iris to cause release of the pigment.

In pigment dispersion syndrome, pigment released from the iris is deposited in other parts of the eye, including the trabecular meshwork-a filter-like tissue in the front of the eye. Aqueous fluid (fluid continuously produced by the eye) normally flows out of the eye through the trabecular meshwork. In some patients, the pigment deposits may block tiny holes in the meshwork, preventing the fluid from flowing out. This can cause an increase in eye pressure that may lead to glaucoma and some loss of vision. Understanding how pigment is released from the iris may help predict the course of pigment dispersion syndrome and identify which patients will likely develop increased eye pressure.

Patients with pigment dispersion syndrome and normal volunteers may be eligible for this study. All participants will have the following procedures, which will be completed in two clinic visits:

First visit

Examination of the front of the eyes, including the cornea, iris and lens.
Vision testing and measurements of visual field and eye pressure.
Examination of the trabecular meshwork. For this test, a contact lens is placed on the eye after the eye has been numbed with anesthetic drops.

Second visit

Refraction (dilation of the pupils with drops) and examination of the back of the eyes, including the optic nerve.
Reaction of the pupils to low-level infrared light (pupillography). During this 15-minute test, the patient or volunteer wears a lightweight headband with two small cameras mounted on it. The cameras-one which views the eye and the other the subject's field of view-record pupil dilation and position.

The test results in patients with pigment dispersion syndrome will be compared with those in normal volunteers. Patients will be followed every 6 months (or more often, if medically indicated) during the 3-year study to determine changes in eye pressure or visual field. Volunteers will be asked to return about once a year for 3 years for repeat pupillography.

Condition
Glaucoma Healthy Pigment Dispersion Syndrome

Genetics Home Reference related topics: early-onset glaucoma

MedlinePlus related topics: Glaucoma

U.S. FDA Resources

Study Type:	Observational
Official Title:	Etiology of Pigment Dispersion Syndrome (PDS)

Further study details as provided by National Institutes of Health Clinical Center (CC):

Estimated Enrollment:	90
Study Start Date:	June 2000
Estimated Study Completion Date:	August 2003

Detailed Description:

The purpose of this study is to conduct a comprehensive ophthalmologic evaluation and comparison of two types of patients and to compare them to normal controls. The two types of patients are those with pigment dispersion (PDS) with normal intraocular pressure (IOP) and those with PDS and elevated IOP.

The hypothesis to be tested is that a developmental abnormality of the iris pigment epithelium (IPE) and the dilator muscle is the fundamental defect responsible for the pigment dispersion. This defect may involve other structures of the eye such as the ciliary and retinal pigment epithelium. The results of pupillography in PDS with or without elevated IOP and asymmetric PDS (one eye versus fellow eye) will be the outcome parameters.

Eligibility

Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	Yes

Criteria

INCLUSION CRITERIA:

All patients entering the study must have black pigment deposition on the trabecular meshwork at the site of Schlemm's canal equal to or greater than 2-plus on the goniophotographic scale of 1 to 5 plus.

Although this condition is rare amongst African-Americans, every effort will be made to recruit such individuals.

EXCLUSION CRITERIA:

Patients with exfoliation syndrome, uveitis, trauma, pigment dispersion with posterior chamber intra-ocular lens, pigmented tumors, primary open-angle glaucoma, other conditions with associated pigment dispersion such as acute angle-closure glaucoma, ocular hemorrhage, Horner's syndrome.

In addition, normal volunteers will be recruited as controls. They will be free of any eye disease and be matched for age, sex and degree of myopia.

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00005919

Locations

United States, Maryland
National Eye Institute (NEI)
Bethesda, Maryland, United States, 20892

Sponsors and Collaborators

National Eye Institute (NEI)

More Information

Publications:

Ferris FL 3rd, Sperduto RD. Standardized illumination for visual acuity testing in clinical research. Am J Ophthalmol. 1982 Jul;94(1):97-8. No abstract available.

Ferris FL 3rd, Kassoff A, Bresnick GH, Bailey I. New visual acuity charts for clinical research. Am J Ophthalmol. 1982 Jul;94(1):91-6.

Study ID Numbers:	000155, 00-EI-0155
Study First Received:	June 17, 2000
Last Updated:	March 3, 2008
ClinicalTrials.gov Identifier:	NCT00005919 History of Changes
Health Authority:	United States: Federal Government

Keywords provided by National Institutes of Health Clinical Center (CC):

Pigment Dispersion
Ocular Hypertension
Glaucoma
Pupil Reaction

Natural History
Pigment Dispersion Syndrome
Gene Mutation
Pigment Dispersion Syndrome

Study placed in the following topic categories:

Glaucoma
Eye Diseases
Healthy

Pigment-dispersion Syndrome
Hypertension
Ocular Hypertension

Additional relevant MeSH terms:

Pathologic Processes
Disease
Glaucoma

Eye Diseases
Syndrome
Ocular Hypertension

ClinicalTrials.gov processed this record on May 07, 2009