Corneal Collagen Crosslinking for Progressive Keratoconus and Ectasia Using Riboflavin/Dextran and Hypotonic Riboflavin
Corneal collagen crosslinking (CXL) has been proposed as an effective method of reducing progression of both keratoconus and corneal ectasia after surgery, as well as possibly decreasing the steepness of the cornea in these pathologies. During the CXL procedure, the central corneal thickness has been shown to significantly change. The investigator's believe that better maintenance of corneal thickness potentially could have benefits of better reproducibility of the crosslinking effect with improved predictability of results.
The objective of this study is to investigate the difference between the two riboflavin preparations during UV (ultraviolet) administration. Both riboflavin preparations currently are in general use worldwide and in U.S. clinical trials of corneal collagen crosslinking. The first preparation contains riboflavin in a dextran solution, which may tend to dehydrate the cornea and keep it thinner. The second preparation contains riboflavin in a solution without dextran; in this case, the relative hypotonicity may tend to keep the cornea better hydrated and thicker. The primary goal of the study is to see if the use of hypotonic riboflavin (rather than riboflavin with dextran) better maintains consistent corneal thickness during the CXL procedure. The second goal of the study is to determine if better maintenance of corneal thickness potentially could have benefits of better consistency of the procedure, decrease in corneal haze formation, and improved safety of the endothelial cells. Safety and efficacy outcomes will then be compared between the groups. In particular, we will compare the corneal thickness measured by ultrasonic pachymetry immediately after the CXL procedure in the randomized eyes. Secondary outcomes will include visual acuity, longer term corneal thickness changes, and corneal steepness changes. Safety assessments will include a tabulation of adverse events, patient symptoms, loss of visual acuity, changes in endothelial cell density, slit lamp examination of the cornea and lens, and contact lens tolerance for contact lens wearers
Allocation: Randomized, Control: Active Control, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment
Riboflavin/Dextran, Hypotonic Riboflavin
Cornea and Laser Eye Institute
Cornea and Laser Eye Institute
Results (where available)
- Source: http://clinicaltrials.gov/show/NCT01152541
- Information obtained from ClinicalTrials.gov on July 15, 2010
Medical and Biotech [MESH] Definitions
An enzyme that catalyzes the formation of riboflavin from two molecules of 6,7-dimethyl-8-ribityllumazine, utilizing a four-carbon fragment from one molecule which is transferred to the second molecule. EC 126.96.36.199.
A dietary deficiency of riboflavin causing a syndrome chiefly marked by cheilitis, angular stomatitis, glossitis associated with a purplish red or magenta-colored tongue that may show fissures, corneal vascularization, dyssebacia, and anemia. (Dorland, 27th ed)
A coenzyme for a number of oxidative enzymes including NADH DEHYDROGENASE. It is the principal form in which RIBOFLAVIN is found in cells and tissues.
A condensation product of riboflavin and adenosine diphosphate. The coenzyme of various aerobic dehydrogenases, e.g., D-amino acid oxidase and L-amino acid oxidase. (Lehninger, Principles of Biochemistry, 1982, p972)
Nutritional factor found in milk, eggs, malted barley, liver, kidney, heart, and leafy vegetables. The richest natural source is yeast. It occurs in the free form only in the retina of the eye, in whey, and in urine; its principal forms in tissues and cells are as FLAVIN MONONUCLEOTIDE and FLAVIN-ADENINE DINUCLEOTIDE.
Corneal ectasia is a relative weakness in the structure of the cornea, which produces a progressive change in its shape which results in visual distortion. It is known that collagen cross...
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