Dynamic Light Scattering for Studying Lens Aging and Cataract Formation
|First Received Date ICMJE||April 28, 2004|
|Last Updated Date||March 3, 2008|
|Start Date ICMJE||April 2004|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE||Not Provided|
|Original Primary Outcome Measures ICMJE||Not Provided|
|Change History||Complete list of historical versions of study NCT00081991 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE||Not Provided|
|Original Secondary Outcome Measures ICMJE||Not Provided|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Dynamic Light Scattering for Studying Lens Aging and Cataract Formation|
|Official Title ICMJE||A Cross Sectional Clinical Study of Human Lens Aging and Cataract Formation, in Vivo, Using Dynamic Light Scattering (DLS)|
This study will use dynamic light scattering (DLS) technology to study normal lens aging and early cataract formation. Cataract is a clouding of the lens that interferes with the passage of light to the retina, impairing visual acuity. DLS uses a low intensity laser light (similar to that used in supermarket checkouts) to measure 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.
Healthy normal volunteers and patients with age-related cataract between 18 and 80 years of age may be eligible for this study. Participants undergo the following tests and procedures:
Eye examination, including the following:
For the DLS procedure, the patient sits in front of the DLS device with his or her chin placed on a chin rest and fixes on a yellow target in the center of the camera lens. When the eye is properly aligned, DLS measurements are taken on the lens.
A new non invasive, in vivo technique to study the molecular changes in the human lens, called Dynamic Light Scattering Device (DLS), has recently been developed. Preliminary studies have shown its potential to detect the earliest changes in cataract, at the stage where anti-cataract treatment would be most effective in reversing, delaying or preventing cataracts. A new miniaturized version of this device has been developed by NASA using lower energy lasers, and under a NASA-NEI Inter Agency Agreement, has been successfully developed into a clinical device at the NEI. We recently conducted pilot studies to evaluate the usefulness and reproducibility of this instrument for quantitating human lens changes, and found good reproducibility. We also derived a useful parameter to use with this new technique, the log mean particle size, derived from particle size distribution data. Preliminary studies have also shown that the NASA-NEI DLS device can be used to detect and monitor molecular changes in early cataract formation as well as in normal aging. We therefore propose to conduct a larger cross sectional clinical study to detect and monitor molecular changes in the lens in early cataract formation and in normal aging.
|Study Type ICMJE||Observational|
|Study Design ICMJE||Not Provided|
|Target Follow-Up Duration||Not Provided|
|Sampling Method||Not Provided|
|Study Population||Not Provided|
|Intervention ICMJE||Not Provided|
|Study Group/Cohort (s)||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Completed|
|Completion Date||April 2005|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
Patients aged 18-80 years will be admitted to this study. There will be no racial or gender bias in the recruitment.
227 patients with AREDS nuclear cataract grades 2 or less will be enrolled in the study. 40 patients with AREDS nuclear cataract grade 3 and 4 will also be enrolled.
For those patients enrolled in the study, both eyes will be evaluated for this protocol. However, the participant has the right to choose to undergo measurements only in one eye. In that case, the eye to be examined will be determined by the partipantt's birth month. If the patient's birth month is an even number, the right eye will be examined; if the patient's birth month is odd, the left eye will be examined.
Subjects who have tear film disorders, corneal opacities or disorders, uveitis, glaucoma or who have difficulty fixating, will be excluded.
Subjects 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, will be excluded.
|Accepts Healthy Volunteers||Yes|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Location Countries ICMJE||United States|
|NCT Number ICMJE||NCT00081991|
|Other Study ID Numbers ICMJE||040166, 04-EI-0166|
|Has Data Monitoring Committee||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||National Eye Institute (NEI)|
|Collaborators ICMJE||Not Provided|
|Investigators ICMJE||Not Provided|
|Information Provided By||National Institutes of Health Clinical Center (CC)|
|Verification Date||April 2005|
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