Test of QLS Device to Detect Early Cataracts

Sponsor
National Eye Institute (NEI) (NIH)
Overall Status
Completed
CT.gov ID
NCT00001617
Collaborator
(none)
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Study Details

Study Description

Brief Summary

This study will test the reliability of an instrument called the Quasi Elastic Laser Scattering Device (QLS) in detecting early changes in cataract formation.

Surgery is currently the only treatment for cataracts. Many laboratories, however, are researching drugs to reverse, delay or prevent cataract formation. Anti-cataract drugs presumably would be most effective given early in the course of disease. When clinical trials of these drugs are begun, dependable and standardized methods for documenting and monitoring lens opacities will be needed to test their effectiveness. The QLS was designed to detect the earliest molecular changes in cataract development. This study will evaluate the usefulness and reliability of this instrument in measuring these changes.

Normal volunteers and patients with cataracts in this study will have a standard eye examination, including a vision test and eye pressure measurement. The pupils will be dilated for QLS testing and for examination of the retina. Photographs of the retina may be taken. The QLS test uses a very dim laser light similar to that used to scan grocery items in the supermarket. The laser beam is projected into the lens of the eye, and the scattered light is collected and analyzed to determine normal and abnormal molecular interactions in the lens. Two measurements will be done for each eye. The test will be repeated in 6 months to determine reproducibility of the system.

Condition or Disease Intervention/Treatment Phase

    Detailed Description

    Recently, a device has been created to determine molecular interactions that occur in the nucleus of the lens, called Quasi Elastic Laser Scattering Device (QLS). Preliminary studies have shown its potential in the detection of the earliest changes occurring in cataract, at the stage where anticataract treatment would theoretically be most effective in reversing, delaying or preventing cataracts. A new miniaturized version of this device has been developed by NASA using low energy lasers and offered for further development and testing at the NEI. We therefore propose to conduct a preliminary study to evaluate the usefulness and reproducibility of this instrument for quantitating lens changes.

    Study Design

    Study Type:
    Observational
    Official Title:
    Feasibility Study - Use of Quasielastic Light Scattering (QLS) Device in a Study of the Human Lens and Lens Opacities
    Study Start Date :
    Sep 1, 1997
    Study Completion Date :
    Aug 1, 2000

    Outcome Measures

    Primary Outcome Measures

      Eligibility Criteria

      Criteria

      Ages Eligible for Study:
      N/A and Older
      Sexes Eligible for Study:
      All
      Accepts Healthy Volunteers:
      Yes

      Patients 18 years or older will be admitted to this study. There will be no gender or sex bias in the recruitment.

      Three subjects who are normal volunteers below age 40 and three subjects who are normal volunteers above age 40 will be recruited. These normal volunteers should have clear lenses with LOCS II clinical score for nuclear opalescence of 0.5 or less.

      In addition, 3 subjects who have early nuclear cataract (LOCS II/Nuclear opalescence -2) will also be recruited for the study.

      QLS data will be obtained on each eye of the normal and cataractous subjects in the nuclear region.

      No patients who have uveitis, glaucoma and who are thought to be at risk for an adverse reaction to pupil dilation, or have a history of allergic reaction to one of the dilating agents that will be used.

      Contacts and Locations

      Locations

      Site City State Country Postal Code
      1 National Eye Institute (NEI) Bethesda Maryland United States 20892

      Sponsors and Collaborators

      • National Eye Institute (NEI)

      Investigators

      None specified.

      Study Documents (Full-Text)

      None provided.

      More Information

      Publications

      Responsible Party:
      , ,
      ClinicalTrials.gov Identifier:
      NCT00001617
      Other Study ID Numbers:
      • 970183
      • 97-EI-0183
      First Posted:
      Dec 10, 2002
      Last Update Posted:
      Mar 4, 2008
      Last Verified:
      Nov 1, 1999
      Keywords provided by , ,
      Additional relevant MeSH terms:

      Study Results

      No Results Posted as of Mar 4, 2008