Effects of Latanoprost on Choroidal Blood Flow Regulation in Human Subjects
Summary
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.
Study Design
Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Diagnostic
Conditions
Ocular Physiology
Intervention
Latanoprost 0.005%, Xalatan®, Placebo
Location
Department of Clinical Pharmacology
Vienna
Austria
1090
Status
Completed
Source
Medical University of Vienna
Results (where available)
Links
- Source: http://clinicaltrials.gov/show/NCT00712400
- Information obtained from ClinicalTrials.gov on February 21, 2012
Medical and Biotech [MESH] Definitions
Accommodation, Ocular
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)
Eye Manifestations
Ocular disorders attendant upon non-ocular disease or injury.
Toxoplasmosis, Ocular
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.
Ocular Physiological Processes
Biological action and events that support the functions of the EYE and VISION, OCULAR.
Therapeutic Misconception
Misunderstanding among individuals, frequently research subjects, of scientific methods such as randomization and placebo controls.
Clinical Trials
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The objective of this study is to investigate how the intraocular pressure (IOP)-lowering effect of the L-PPDS is altered by adjunctive Xalatan therapy.
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Ocular Surface Effects of Prostaglandin Analogues (PGAs)
The objective of this study is to examine the affect on tear film break up time (TBUT) of changing patients on Xalatan® therapy to TRAVATAN Z®.
The purpose of this study is to demonstrate that fixed combination of latanoprost and timolol (PhXA41) has better IOP lowering effect than the individual monotherapies.
PubMed Articles
A review of the use of latanoprost for glaucoma since its launch.
Introduction: Prostaglandins are increasingly used as first choice treatment for glaucoma because they are highly effective, lack relevant systemic side effects and require just once-daily administrat...
The intraocular pressure reducing effect of brinzolamide as adjunctive therapy to latanoprost.
Abstract Aim: To determine the intraocular pressure (IOP) lowering effect of brinzolamide when added to latanoprost. Materials and methods: Patients who were simultaneously on brinzolamide and latanop...
Changes to upper eyelid orbital fat from use of topical bimatoprost, travoprost, and latanoprost.
PURPOSE: To confirm the possible mechanism by which topical prostaglandin antiglaucoma drugs cause a deep superior sulcus. METHODS: Among patients who used bimatoprost (Lumigan), latanoprost (Xalatan)...
PURPOSE: To prospectively assess the efficacy of switching to a travoprost/timolol fixed-combination (TTFC) therapy from latanoprost monotherapy. METHODS: This was a prospective, open-label study in w...
The stabilization mechanism of latanoprost.
The content of latanoprost is likely to decrease in solution because of the adsorption to eye drop containers and hydrolysis. We reduced these problems and established a formulation of latanoprost eye...
