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The Zeaxanthin and Visual Function Study

Not Applicable
Completed
Conditions
Cognition Disorders
Age Related Macular Degeneration
Interventions
Dietary Supplement: Lutein
Dietary Supplement: Lutein and Zeaxanthin
Drug: 3R 3'R Zeaxanthin
Registration Number
NCT00564902
Lead Sponsor
Chrysantis, Inc.
Brief Summary

To evaluate if supplementation of zeaxanthin (with or without Lutein) is beneficial to patients with early and moderate Atrophic Age Related Macular Degeneration.

Detailed Description

To evaluate whether or not zeaxanthin supplementation raises macular pigment optical density (MPOD). Previous research has shown MPOD to mirror visual benefits for patients with age related atrophic macular degeneration (AMD) having visual symptoms (decreased visual acuity, contrast sensitivity, photostress glare recovery and National Eye Institute Visual Function Questionnaire 25 scores), but lower risk National Eye Institute (NEI) / Age Related Eye Disease Study (AREDS) characteristics.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
60
Inclusion Criteria
  • diagnosis of atrophic AMD (ICD9 362.51) by stereo bio-ophthalmoscopy and at least one vision degrading visual-psychophysical abnormality associated with AMD in one or both eyes.
  • clear non-lenticular ocular media (cornea, aqueous and vitreous)
  • free of advanced glaucoma and diabetes or any other ocular or systemic disease that could affect central or parafoveal macula visual function
Exclusion Criteria
  • high risk retinal characteristics for advanced AMD or advanced AMD for which existing medical / surgical options are available
  • presence of ophthalmologically significant active exudative, AMD pathology by fluorescein angiography but also a single large drusen, >15, multiple intermediate drusen, parafoveal geographic atrophy or loss of vision in one eye due to advanced AMD
  • recent (within 6 months) cataract or retinal surgery
  • taking photosensitizing drugs such as phenothiazines and chloroquine
  • having taken lutein or zeaxanthin supplements within the past six months.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
LuteinLutein9 mg of Lutein for 12 months
Zeaxanthin and LuteinLutein and Zeaxanthin3R 3'R Zeaxanthin 8 mg, Lutein 8 mg per day during 12 months
Zeaxanthin3R 3'R Zeaxanthin3R 3'R Zeaxanthin 8 mg per day during 12 months
Primary Outcome Measures
NameTimeMethod
Macular Pigment Optical Density12 months

Replicate measures of foveal 1 degree estimated central MPOD were evaluated with the Quantify® MPS 9000 macular pigment screener, a modified heterochromic flicker photometer (HFP). It employs alternating blue and green flickering light emitting diodes and fixation on a 1 degree target, so that a representative measurement at 0.5 degree off center from the fovea is calculated.

Secondary Outcome Measures
NameTimeMethod
SHAPE Discrimination12 months

We determined the target deformation detection thresholds, or amplitude of the minimum detectable distortion of a 1 degree foveal circular target. The peak spatial frequency of RF (radial frequency) patterns was 5 cyc/deg; the radial modulation frequency was 8 cyc/360°; mean radii were 0.5°, 1°, 2.0°, or 2.5°; and stimulus contrast was 80%. The highest % modulation score possible is 0.13 while the easiest (lowest score) was 10% modulation.

Glare Recovery12 Months

Photostress glare recovery test involves exposing an individual eye to intense light, or retinal bleach, for a set duration of time and measuring the time taken for visual acuity to recover to a predetermined level. Glare photo-stress recovery (in seconds) following 30 seconds of continuous retinal bleach, was assessed using 2 line supra-threshold low contrast randomly presented Landolt Cs using the KOWA AS14B Night Vision Tester (KOWA Optimed, Tokyo, Japan).

6.5 Degrees Tritan Threshold12 months

The ChromaTest© is a computerized psychophysical test of protan and tritan color thresholds against age-corrected data. The computer finds the endpoint of the test by a Modified Binary Search method; if response is correct, on the next presentation the color difference between letter and background is halved. If response is incorrect, the color -contrast is doubled. Incorrect responses prolong the test, but do not influence the final threshold. This method of determining thresholds leads to finite steps which reach a plateau at the color contrast sensitivity threshold.

Early Treatment Diabetic Retinopathy Study Distance Visual Acuity12 months

Black and 10% contrast near reading visual acuity was assessed with a Colenbrander Mixed Contrast Reading Card with LogMAR letters (#4031, Precision Vision, LaSalle, Illinois). We determined single letter acuity on an ordinal VAS (Visual Acuity Scale). The largest letters were 0.05 LogMAR with a VAS = 35 while the most difficult smallest letters were LogMar 1.25 or VAS 105. The test card was held at 40 cm with best monocular refraction, and both low and high contrast letter acuity were assessed.

Contrast Sensitivity Function Photopic Distance12 Months

Distance photopic contrast sensitivity function (CSF) at 5 spatial frequencies (1.5, 3, 6, 12 \& 20 cc/deg) was determined with the Functional Vision Analyzer® (Stereo Optical Co, Inc, Chicago, IL). Contrast sensitivity readings are shown as a curve. Visual acuity is plotted along the horizontal axis and contrast sensitivity along the vertical axis. Among the normally sighted people, both visual acuity and contrast sensitivity have a wide range of variation.Low population CSF is 0-200 units; normal population CSF is 200-300 units and suprathreshold CSF is 300+ units.

100% Kinetic Field12 Months

Scotomas within the central 20 degree central macula visual field sensitivity was assessed at 5 contrast levels (20, 40, 60, 80, and full contrast). A yellow wavelength stimulus avoided confounding by the lens. Subjects outlined the boundaries of their scotoma(s) on an area-integrating and recording touch flat- screen RGB monitor displaying a central fixation point and movable horizontal/vertical raster lines. The computer calculated summed area of the scotoma(s) with arbitrary scaling from 6000 (dense scotoma) to 0 relative units (absence of scotoma).

Trial Locations

Locations (1)

North Chicago VA Medical Center

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North Chicago, Illinois, United States

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