Effects of Vitamin C on Hyperoxia-Induced Reduction of Retinal Blood Flow

Status Completed

Clinical Trial Summary

High arterial blood oxygen tension leads to vasoconstriction of retinal vessels, possibly related to an interaction between reactive oxygen species and endothelium-derived vasoactive factors. Vitamin C is a potent antioxidant capable of reversing endothelial dysfunction due to increased oxidant stress. Vitamin C appears to have vasodilatory properties, but the underlying mechanisms are not well understood.

In the present study we hypothesized that hyperoxic vasoconstriction of retinal vessels could be diminished by vitamin C.

Ocular blood flow will be determined by non-invasive methods, including laser Doppler velocimetry and the Zeiss retinal vessel analyser.

Clinical Trial Description

n/a

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Diagnostic

Related Conditions & MeSH terms

Clinical Trial Details

NCT number	NCT00712907
Study type	Interventional
Source	Medical University of Vienna
Contact
Status	Completed
Phase	N/A
Start date	February 2003
Completion date	May 2003

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