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Pilot Study: Dynamic Light Scattering Device for Studying Early Changes in Cataract

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: NCT00067483
Recruitment Status : Completed
First Posted : August 21, 2003
Last Update Posted : July 2, 2017
Information provided by:
National Institutes of Health Clinical Center (CC)

Brief Summary:

This study will use a new dynamic light scattering device (DLS), developed jointly by NASA and the NEI, to study pre-senile cataracts (cataracts that develop in patients 55 years old or less). Cataract is a clouding of the lens that interferes with the passage of light to the retinal, impairing visual acuity. DLS uses a low intensity laser light (similar to that used in supermarket checkouts) to measures lens cloudiness. It detects changes in the human lens at the earliest molecular stages of cataract development, when anti-cataract treatment would be most effective in reversing, delaying or preventing cataract formation.

Patients 55 years of age or younger with cataract may be eligible for this study. Candidates will be screened with the following tests and procedures:

  • Medical history and physical examination.
  • Eye examination, including measurement of visual acuity (vision chart) and eye pressure; examination of pupils and eye movements; dilation of the pupils for examination of the lens and the back of the eye (retina).
  • Cataract photography using a camera with a bright flash to assess the status of the cataract and evaluate future changes.
  • Blood drawing if necessary for clinical care.

Participants will have a standard eye examination, as described above, plus DLS testing. For this procedure, the patient sits in front of the DLS device, with the chin placed on a chin rest. He or she fixes on a yellow-green target in the center of the camera lens. When the eye is properly aligned, the measurement is taken and the reddish light on the side of the camera lens turns on for 5 seconds. Measurements are taken on three layers of the lens. The procedure takes less than 30 minutes.

Participants will be followed at the NIH clinic once a month for up to 1 year to follow progression of the cataract. The visits will include a repeat of some of the exams listed above.

Condition or disease

Detailed Description:
Recently, a device has been created to determine molecular interactions that occur in the human lens in vivo and non-invasively, called Dynamic Light Scattering Device (DLS). Preliminary studies have shown its potential in the detection of the earliest changes occurring in cataract, at the stage where anti-cataract treatment would theoretically be most effective in reversing, delaying or preventing cataracts. A new DLS device has been developed by NASA physicist Dr. Rafat Ansari using lower energy lasers, miniaturized and contained within a fiber optic tip, and further developed and tested under an NEI-NASA Inter Agency Agreement. We recently conducted a pilot study to evaluate the usefulness and reproducibility of this instrument for quantitating lens changes, and found good reproducibility. We also determined that a useful parameter is mean particle size. We therefore propose to use the new NEI-NASA DLS device to detect and study, non-invasively and in vivo, the earliest molecular cataractous changes that develop rapidly in the lenses of patients less than 55 years of age, otherwise called pre-senile cataracts.

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Study Type : Observational
Enrollment : 15 participants
Official Title: Pilot Study on the Use of the NASA-NEI Dynamic Light Scattering (DLS) Device in Detecting Lens Changes in the Other Eye of Patients With Pre-Senile Cataracts
Study Start Date : August 15, 2003
Study Completion Date : December 10, 2007

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Cataract

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years to 55 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Patients 55 years of age or younger with cataracts (pre-senile cataracts) will be admitted to this study.

Ten subjects who have cataracts and who are 55 years of age or younger, of either sex, will be recruited. DLS data will be obtained on the eye with no or little cataract every month for a year or until cataract surgery is required. AREDS grading will be utilized but will not be used as a protocol end point.


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.

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): NCT00067483

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United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
United States, Ohio
NASA-John Glenn Research Center
Cleveland, Ohio, United States
Sponsors and Collaborators
National Eye Institute (NEI)
Layout table for additonal information Identifier: NCT00067483    
Other Study ID Numbers: 030275
First Posted: August 21, 2003    Key Record Dates
Last Update Posted: July 2, 2017
Last Verified: December 10, 2007
Keywords provided by National Institutes of Health Clinical Center (CC):
Dynamic Light Scattering (DLS)
Light Scattering
Additional relevant MeSH terms:
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Lens Diseases
Eye Diseases