Publications by authors named "F Lexer"

We describe basic principles of wavelength-tuning interferometry and demonstrate its application in ophthalmology. The advantage of this technique compared with conventional low-coherence interferometry ranging is the simultaneous measurement of the object structure without the need for a moving reference mirror. Shifting the wavelength of an external-cavity tunable laser diode causes intensity oscillations in the interference pattern of light beams remitted from the intraocular structure.

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Background: There is experimental evidence that retinal blood flow is impaired in patients with diabetes mellitus. Much less attention has been paid to choroidal blood flow. Hence it was the aim of the present study to investigate choroidal blood flow in diabetic retinopathy.

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There is experimental evidence that endothelium derived nitric oxide is involved in the regulation of ocular vascular tone. The purpose of this study was to investigate the effects of NO-synthase inhibition by N-monomethyl-L-arginine (L-NMMA) on ocular fundus pulsations in young healthy volunteers. Three milligrams per kilograms L-NMMA were administered i.

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The effect of different mixtures of O2 and CO2 on pulsatile ocular blood flow as assessed by laserinterferometric measurement of fundus pulsations was studied. This was done in an effort to identify the gas mixture with an optimal O2/CO2 ratio for treatment in central retinal artery occlusion (CRAO). In a double-blind, randomized, placebo-controlled, six-way cross-over study, 20 healthy young subjects were studied.

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Purpose: To estimate the short-term effects of pentoxifylline on ocular blood flow in healthy volunteers.

Methods: In ten healthy subjects, either 200 or 400 mg of pentoxifylline or placebo was administered intravenously over 90 minutes in a randomized, double-blind, placebo-controlled, three-way crossover study design. Noninvasive measurements of blood pressure, pulse rate, flow variables in the radial artery, ocular fundus pulsations, and whole blood viscosity and filterability were performed at baseline and at 30-minute intervals until four hours after the start of drug infusion.

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