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ZeaVision is pleased to announce the return of the 10mg zeaxanthin product
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| Boston, MA, June 28, 2007 6:00a.m. - 7:30a.m
:: ZeaVision sponsors an American Optometric Association Continuing Education Course: |
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| St. Louis, MO, April, 2007
:: ZeaVision Adds Two More Prominent Doctors to its Advisory Board. |
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| St. Louis, MO, August 28, 2006
:: ZeaVision Adds Three Leading Doctors to its Advisory Board. |
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| St. Louis, MO August 11, 2006
:: Joseph M. Strout named new Chief Financial Officer and member of the Executive Committee for ZeaVision, LLC
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| St. Louis, MO June 2, 2006
::Community Benefits from Eye Studies Conducted by the College of Optometry at the University of Missouri-St. Louis and ZeaVision
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| ST. LOUIS, MO, May 24, 2006
::St. Louis Business Eyes Local Market As First In Country To Screen For AMD Risk
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| May, 2006
::ZeaVision, LLC Announces Three New Business Developments
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Assess AMD Risk
Device enables assessment of key
AMD risk factor. (N . Rex Ghormley , O.D. , F.A.A.O. , And
Jack J . Yager , O.D. , F.A.A.O.)
Age-related macular degeneration
(AMD) is the leading
cause of blindness for
Americans age 55 and
older, with more than 10 million
Americans currently grappling with
the sight-stealing disease, according
to the AMD Foundation. As a result,
to prevent vision loss and preserve
your patients’ quality of life,
you must accurately determine
AMD risk.
QuantifEye, from ZeaVision
LLC, helps you to do this.How so?
It measures the density of theMacular
Pigment — a key AMD risk
factor — via heterochromatic
flicker photometry.
Here, we explain why this is important
and how, specifically, the
device works.
Assess AMD Risk
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Macular pigment: New clinical methods of detection and
the role of carotenoids in age-related macular
degeneration (Ivan Y-F. Leung, Ph.D., M.Phil.)
Abstract: Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in
people over the age of 65. The Age-Related Eye Disease Study (AREDS) suggests antioxidants may
delay the advance of age-related macular degeneration. The macular pigments zeaxanthin and lutein
may serve as antioxidants as well as blue filter to protect the retina. In this review, the general
characteristics of macular pigment are described. The nutritional value of zeaxanthin/lutein and
methods to assess macular pigment are discussed. Several emerging instruments to assess macular
pigment, including heterochromatic flickering photometer, motion detection photometer, fundus reflectance
spectroscope, Raman spectrometer, and autofluorescence spectrometry, are introduced and
reviewed. Optometrists should be aware that they may play a role to assess and monitor the risk of
AMD. There is an opportunity to incorporate measurement of macular pigment in optometric practice.
Optometry 2008;79:266-272
Leung - Macular Pigment
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Assessment of the
Validity of in Vivo Methods of Measuring Human Macular Pigment Optical Density
(Hammond and Wooten) Optometry and Vision Science
Purpose: As a result of the putative protective role
of lutein and zeaxanthin at the site of the retina (macular pigment [MP]), interest in the noninvasive
measurement of these retinal carotenoids is increasing. In principle, any method used to measure MP in vivo
should provide spectral absorption curves that match extinction spectra of MP measured ex vivo.
Method: In this article, we assess published
spectral curves with respect to this criterion.
Results: Variation in derived MP measures
resulting from methodological differences between techniques is noted and discussed.
Click here to read the full article
(C) 2005 American Academy of Optometry
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Heterochromatic Flicker Photometry
(Bone and Landrum) Science Direct
Measurement of the macular pigment optical
density (MPOD) by heterochromatic flicker photometry (HFP) is accomplished by viewing a small
circular stimulus that alternates between a test wavelength that is absorbed by the MP
(typically— blue, 460 nm) and a reference wavelength that is not absorbed (typically—green, 540 nm).
Flicker observed by the subject is reduced to a null point by adjusting the intensity
of the former while viewing the stimulus centrally, and then peripherally. A higher
intensity, I, of the blue component of the stimulus is needed under central viewing
conditions owing to attenuation by the MP. The MPOD at the test wavelength is given
by log (Icentral/Iperipheral). Variation of the test wavelength has been used to
measure the MPOD spectrum. This in vitro MPOD spectrum matches that of the
carotenoids present in the macular region of the retina and demonstrates the
validity and specificity of this methodology. The distribution of MPOD in the
retina can be determined with HFP using a series of annular stimuli of different
diameters.
Click here to read the full article
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Nutrition and
the Eye: How and Why to Fortify HighBeam Research
In the past few years, we Americans have increased our intake of vitamins and minerals to enhance our health. For instance, more than 50% of elderly persons currently use some form of dietary supplement. (1) Sales of supplements in the United States topped $20.3 billion in 2004 (an increase of nearly 13% since 2001). (2) National Institutes of Health funding for dietary supplement research topped $117 million in 2002, with over 350 research projects currently under way.
An impressive body of research clearly shows nutritional support can affect the development of eye ...
Click here to read the full article
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LAST Study (Richer)
Nutrition 4 Health
Purpose: The objective of the LAST
(Lutein Antioxidant Supplementation Trial) trial was to determine whether specific
dietary interventions might improve visual function in patients with atrophic ARMD
(Optometry, 2004;75:216-30). The current LAST II objective was to discern
characteristics that might differentiate responder from non-responder.
Methods: The LAST study was a prospective, 12-month, randomized, double-masked,
placebo-controlled trial conducted at an urban midwestern Veterans Administration
Hospital from August, 1999, to May, 2001. Ninety patients with atrophic ARMD entered
the study and were randomly assigned to groups. Patients in Group 1 received 10 mg
lutein; in Group 2, 10 mg lutein in combination with vitamins, minerals, and
antioxidants; and in Group 3, maltodextrin placebo. Changes in macular pigment
optical density (MPOD) over time were evaluated. Characteristics potentially
influencing response included age, weight (BMI), initial baseline values of
macular pigment, and combining xanthophylls with other nutrients.
Results: MPOD increased with
supplementation and declined slightly without
supplementation (regression slopes not equal to zero in supplemented groups,
p < 0.02). The highest increases in MPOD over time occurred in patients with
lower baseline values of MPOD. Statistically significant increases in MPOD
density were observed in the Lutein group for patients with baseline MPOD
= 0.3 optical density units and up to 0.2 optical density units in the
Lutein + Antioxidant group. Further analysis demonstrated that none of
the subject eyes in the lowest quartile of baseline MPOD were in the
lowest quartile for change in macular pigment optical density.
Conclusions: Noteworthy is the
observation that those individuals with
lowest MPOD, and in greatest need of supplementation, also were most
likely to benefit from either the lutein or the lutein + antioxidant
supplementation. For those individuals who responded to supplementation,
their macular pigment optical density had not ceased to increase at 12
months’ duration of Supplementation. The inference is that if a deficiency
in macular pigment optical density is accurately diagnosed, effective
interventions should be able to re-establish this prophylactic barrier.
(In Review, Optometry, Journal of the American Optometric Association)
Click here to read the full article
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LAST II:
Differential temporal
responses of macular pigment optical density in patients with atrophic age-related
macular degeneration to dietary supplementation with xanthophylls. (Richer, Evenport, Lang)
PubMed
Department of Veterans Affairs,
Medical Center Eye Clinic, North Chicago, Illinois; Family Medicine/Chicago Medical School, North Chicago, Illinois.
Background: Age-related macular degeneration
(ARMD) is the leading cause of vision loss in aging Western societies. The objective of the Lutein
Antioxidant Supplementation Trial (LAST) was to determine whether specific dietary interventions
increased macular pigment optical density (MPOD) and visual function in patients with atrophic
ARMD. The current objective of LAST II is to discern those specific characteristics that increase
MPOD, i.e., that might differentiate a responder from a nonresponder.
Methods: The LAST study was a
prospective, 12-month, randomized, double-masked, placebo-controlled trial conducted at an
urban midwestern Veterans Administation Hospital from August 1999 to May 2001. Ninety patients
with atrophic ARMD entered the study and were assigned randomly to 1 of 3 groups. Patients
in group 1 received 10 mg lutein; in group 2, 10 mg lutein in combination with vitamins,
minerals, and antioxidants; and in group 3, maltodextrin placebo. Changes in macular MPOD
over time were evaluated. Characteristics potentially influencing MPOD included age,
weight (body mass index), initial baseline values of macular pigment, and combining
xanthophylls with other nutrients.
Results: MPOD increased with
supplementation and declined slightly without supplementation (regression slopes not equal
to zero in supplemented groups, P < 0.02). The highest increases in MPOD over time occurred
in patients with lower baseline values of MPOD. Statistically significant increases in MPOD
density were observed in the lutein group for patients with baseline MPOD
Conclusions: Noteworthy is the
observation that those individuals with lowest MPOD, and in greatest need of supplementation,
were also most likely to benefit from either the lutein or the lutein plus antioxidant
supplementation. For those individuals who responded to supplementation, their macular
pigment optical density had not ceased to increase at 12 months' duration of supplementation.
The inference is that if a deficiency in macular pigment optical density is accurately diagnosed,
effective interventions should be able to re-establish this prophylactic barrier.
PMID: 17478338 [PubMed - in process]
Click
here to read the full article
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POLA Study
Archives Of Ophthalmology
Purpose: The macular pigment, formed of lutein and zeaxathin, is thought to protect against
retinal damage by filtering out phototoxic short-wavelength visible light and by defending rod
outer segment membranes from oxidative stress. Although several epidemiological studies have
suggested a reduced risk of age-related maculopathy (ARM) in subjects with high dietary and/or
plasma levels of lutein and zeaxanthin, epidemiological data remain scarce and partly inconsistent. In
the present report, they separately assessed the associations of plasma lutein and zeaxanthin as well as
that of other carotenoids with the risk of ARM, in a Mediterranean population-based study.
Methods: The POLA Study is a population-based study performed on the French Mediterranean, and aiming
at the identification of risk factors for ARM and cataract. Retinal photographs were graded according
to the international classification. ARM was defined by the presence of late ARM (neovascular ARM,
geographic atrophy) and/or soft indistinct drusen (>125 µm) and/or soft distinct drusen (>125 µm)
associated with pigmentary abnormalities. Plasma carotenoids were measured by HPLC from plasma
samples collected at the baseline examination, in 899 subjects of the cohort. Among those, photographs
gradable for ARM were available in one eye at least of 644 subjects (72 %).
Results: After multivariate adjustment, the highest quintile of plasma zeaxanthin was significantly
associated with reduced risk for ARM (OR = 0.07 (95 % confidence interval (CI) : 0.01 -0.58), p for
trend = 0.005). Risk for ARM was also inversely associated with combined plasma lutein and
zeaxanthin (OR= 0.21 (95 % CI: 0.05 -0.79), p for trend= 0.01), and tended to be associated with
plasma lutein (OR= 0.31 (95 % CI: 0.09 -1.07), p for trend= 0.04). Other carotenoids (alpha- and
beta-carotene, beta-cryptoxanthin, lycopene) did not show significant associations with ARM.
Conclusions: These results are consistent with previous epidemiological studies and are strongly suggestive
of a protective role of the xanthophylls, in particular zeaxanthin, for the protection against ARM.
They need to be confirmed by other studies, in particular prospective epidemiological and interventional studies.
Click here to read the full article
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Macular Pigment:
A review of current knowledge
Archives Of Ophthalmology
The existence of the macula lutea of the human retina has been known for more than 200 years. It is established that the xanthophylls lutein and zeaxanthin are responsible for the yellow color. The effect of macular photopigments on blue-light filtration and color perception is well established. It has been postulated that the pigment might serve to reduce chromatic aberration and to improve visual acuity. The antioxidant capabilities of these xanthophylls combined with their ability to trap short-wavelength light may serve to protect the outer retina, retinal pigment epithelium, and choriocapillaris from oxidative damage. Current ideas on the pathophysiology of age-related macular degeneration may be compatible with the proposed function of lutein and zeaxanthin. This review will summarize our knowledge about macular pigment regarding current efforts in research and the epidemiology of age-related eye disease.
Click here to read the full article
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Risk Factors for
Age-Related Maculopathy Are Associated With a Relative Lack of Macular Pigment (NOLAN)
PubMed
Macular pigment (MP) is composed of the two dietary carotenoids lutein (L) and zeaxanthin (Z), and is believed to protect against age-related maculopathy (ARM). This study was undertaken to investigate MP optical density with respect to risk factors for ARM, in 828 healthy subjects from an Irish population. MP optical density was measured psychophysically using heterochromatic flicker photometry, serum L and Z were quantified by HPLC, and dietary intake of L and Z was assessed using a validated food-frequency questionnaire. Clinical and personal details were also recorded, with particular attention directed towards risk factors for ARM. We report a statistically significant age-related decline in MP optical density (r2=0.082, p<0.01). Current and past smokers had lower average MP optical density than never smokers and this difference was statistically significant (p<0.01). Subjects with a confirmed family history of ARM had significantly lower levels of MP optical density than subjects with no known family history of disease (p<0.01). For each of these established risk factors, their statistically significant negative association with MP persisted after controlling for the other two, and also after controlling for other potentially confounding variables such as sex, cholesterol, dietary and serum L (p<0.01). In the absence of retinal pathology, and in advance of disease onset, the relative lack of MP seen in association with increasing age, tobacco use and family history of ARM supports the hypothesis that the enhanced risk that these variables represent for ARM may be attributable, at least in part, to a parallel deficiency of macular carotenoids.
Click here to read the full article
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