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PURPOSE Dietary carotenoids lutein and zeaxanthin may play a protective role against visual loss from age-related macular degeneration (AMD) through antioxidant and light screening mechanisms. We used a novel noninvasive objective method to quantify lutein and zeaxanthin in the human macula using resonance Raman spectroscopy and compared macular pigment(More)
PURPOSE To develop and test a novel noninvasive optical technique suitable for the objective measurement of macular carotenoid levels in human retina. METHODS A resonance Raman scattering apparatus was constructed to measure carotenoid levels in flat-mounted human retinas and eyecups and in experimental animal eyes. Light from an argon laser was used to(More)
We have used resonant Raman scattering spectroscopy as a novel, noninvasive, in vivo optical technique to measure the concentration of the macular carotenoid pigments lutein and zeaxanthin in the living human retina of young and elderly adults. Using a backscattering geometry and resonant molecular excitation in the visible wavelength range, we measure the(More)
Carotenoids are thought to play a significant part in the skin's anti-oxidant defense system, and may help prevent malignancy. Inability to measure skin carotenoid content readily has, however, made it difficult to establish the relationship between carotenoid concentration and the occurrence of cutaneous malignancy. We have measured in vivo carotenoid(More)
We have used resonance Raman scattering as a novel noninvasive optical technology to measure carotenoid antioxidants in living human tissues of healthy volunteers. By use of blue-green laser excitation, clearly distinguishable carotenoid Raman spectra superimposed on a fluorescence background are obtained. The Raman spectra are obtained within less than a(More)
Laser fragmentation is a promising new modality in management of retained CBD stones. Recent reports demonstrate the feasibility of lasers for this, but few studies have evaluated their safety (e.g., thermal injury may occur at greater than 43 degrees C). This study was conducted to measure heat transmission from lased bilirubinate and mixed stones to a(More)
We have used resonant Raman scattering as a novel, noninvasive in vivo optical technique to measure the concentration of macular carotenoid pigments in the living human retina. Using a backscattering geometry and resonant molecular excitation in the visible, we measure the Raman peaks that originate from the single- and double-bond stretch vibrations of the(More)
OBJECTIVE The objective of these 2 studies was to assess the efficacy of FL-41-tinted lenses in the treatment of benign essential blepharospasm (BEB). DESIGN A randomized crossover study and a randomized crossover case-control study. PARTICIPANTS The first study included 30 subjects with BEB. The second study included 26 subjects with BEB and 26(More)
We have imaged the spatial distribution of macular carotenoid pigments (MPs) in the human retina, employing Raman spectroscopy. Using excised human eyecups as initial test samples and resonant excitation of the pigment molecules with narrow-bandwidth blue light from a mercury arc lamp, we record Raman images originating from the carbon-carbon double-bond(More)
Application of 630 nm light in the presence of blood is often necessary during photodynamic therapy, particularly for proposed intravascular applications. The effect of blood on transmission of 630 nm light was studied using a three dimensional irradiation model and an integrating sphere for measuring light transmitted in any direction through blood layers(More)