Pigment Dispersion Syndrome: Natural History and Possible Protective Effect of a YAG Laser Iridotomy

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01053416
Recruitment Status : Completed
First Posted : January 21, 2010
Last Update Posted : January 22, 2010
Information provided by:
University of Parma

Brief Summary:


  1. To determine the 10-year conversion rate from pigment dispersion syndrome (PDS) to pigmentary glaucoma (PG)
  2. To evaluate the possible protective effect of a Yag-laser iridotomy

Condition or disease Intervention/treatment Phase
Pigment Dispersion Syndrome Procedure: Yag laser iridotomy Not Applicable

Detailed Description:

1154 workers in the Parma area will be screened for eligibility to long-term use of video-monitors. Those referred to the Glaucoma Clinic for suspected PDS will be enrolled in the study.

In a prospective study on the natural history of PDS and PG, Richter et al. (Arch Ophtal 104:211-5, 1986) found an association between "active pigment dispersion" and elevated IOP. Therefore, in order to evaluate the "stability" of the pigment, a phenylephrine test will be performed following the method reported by Epstein et al (1978) AJO 85:43-50. The test will be performed by one investigator (SAG)and was considered positive if > "grade 1+" (i.e. at least 10 particles in a single light beam). Eyes showing a positive test will be considered as "high-risk" for conversion to PG.

Yag laser iridotomy will be performed in patients showing both eyes at high risk. One eye only (randomly chosen) will be treated. the fellow eye will be left untreated and considered as internal control.

Low risk eyes will be followed without any intervention.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 72 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Investigator)
Primary Purpose: Prevention
Official Title: 10-year Follow up of Patients With Pigment Dispersion Syndrome: Risk Factors for Conversion to Pigmentary Glaucoma and Potential Protective Effect of a Yag-laser Iridotomy in High Risk Eye
Study Start Date : January 1993
Actual Primary Completion Date : April 2003
Actual Study Completion Date : December 2003

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Glaucoma

Arm Intervention/treatment
No Intervention: observation
Experimental: Yag laser iridotomy
the enrolled eyes will undergo an iridotomy performed by using a Yag-laser
Procedure: Yag laser iridotomy
the procedure will be performed by using a Yag laser. Single spot, 1 mJ power, beam aimed to an existing iris crypt
Other Name: iridectomy

Primary Outcome Measures :
  1. > 5 mmHg IOP increase vs baseline (average 2 highest readings, 8 am - 6 pm phasing, 6 readings) [ Time Frame: 10 years ]

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Ages Eligible for Study:   Child, Adult, Older Adult
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Krukenberg spindle
  • Slit-like mid peripheral iris defect
  • Pigment in > 270° of AC angle

Exclusion Criteria:

  • IOP > 18 mmHg
  • PEX (full mydriasis)
  • w/w field defect (Octopus G1 program)

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01053416

Sezione Di Oftalmologia, Universita' Di Parma
Parma, Italy, 43100
Sponsors and Collaborators
University of Parma

Publications automatically indexed to this study by Identifier (NCT Number):
Other Study ID Numbers: PARMAPIGMO
First Posted: January 21, 2010    Key Record Dates
Last Update Posted: January 22, 2010
Last Verified: January 2003

Keywords provided by University of Parma:
pigmentary glaucoma
laser iridotomy

Additional relevant MeSH terms:
Glaucoma, Open-Angle
Pathologic Processes
Ocular Hypertension
Eye Diseases