Effects of Latanoprost on Choroidal Blood Flow Regulation in Human Subjects
Latanoprost is a synthetic prodrug of 17-phenyl-substituted prostaglandin F2α analog. Used at a dose of one drop per day, it has been reported to produce a 30 to 35% reduction in intraocular pressure. Its mechanism of activation involves augmentation of the eye's natural uveoscleral outflow capacity .
There is evidence that ocular blood flow plays a role in the clinical course of glaucoma. Glaucoma medication that lowers IOP simultaneously increases ocular blood perfusion pressure, which in turn may increase ocular blood flow.
This could well contribute to the partially contradicting results concerning ocular hemodynamic effects of latanoprost. In vitro studies indicate that latanoprost has no effect on ocular vascular tone in therapeutical doses. By contrast, it has been reported in several studies that latanoprost 0.005% increases pulsatile ocular blood flow in patients with primary open angle glaucoma and normal tension glaucoma. This increase in pulsatile ocular blood flow mainly reflects an increase in the choroidal circulation.
Little is known about the potential effect of latanoprost on choroidal blood flow regulation in humans. The present study therefore tries to elucidate whether treatment with latanoprost may alter choroidal blood flow regulation during artificial changes in ocular perfusion pressure. In addition, the present study aims to clarify whether the change in choroidal blood flow after latanoprost administration are due to direct vasoactive effects or due to the increase in ocular perfusion pressure. The second alternative may have important implications on our understanding of glaucoma treatment, because reduction of IOP may then per se result in normalization of ocular blood flow regulation.
Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Diagnostic
Latanoprost 0.005%, Xalatan®, Placebo
Department of Clinical Pharmacology
Medical University of Vienna
Results (where available)
- Source: http://clinicaltrials.gov/show/NCT00712400
- Information obtained from ClinicalTrials.gov on February 21, 2012
Medical and Biotech [MESH] Definitions
The dioptric adjustment of the EYE (to attain maximal sharpness of retinal imagery for an object of regard) referring to the ability, to the mechanism, or to the process. Ocular accommodation is the effecting of refractive changes by changes in the shape of the CRYSTALLINE LENS. Loosely, it refers to ocular adjustments for VISION, OCULAR at various distances. (Cline et al., Dictionary of Visual Science, 4th ed)
Ocular disorders attendant upon non-ocular disease or injury.
Infection caused by the protozoan parasite TOXOPLASMA in which there is extensive connective tissue proliferation, the retina surrounding the lesions remains normal, and the ocular media remain clear. Chorioretinitis may be associated with all forms of toxoplasmosis, but is usually a late sequel of congenital toxoplasmosis. The severe ocular lesions in infants may lead to blindness.
Biological action and events that support the functions of the EYE and VISION, OCULAR.
Misunderstanding among individuals, frequently research subjects, of scientific methods such as randomization and placebo controls.
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