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Corneal ectasia is characterized by irregularity and thinning of the cornea, causing the cornea to bulge forward and cause distorted vision and impaired visual acuity. Corneal ectasia is a complication after refractive (LASIK) surgery. It is also the primary problem in keratoconus, a gradually progressive inherited condition that typically is manifested in young adulthood, more commonly in women. Treatment approaches to stabilize the cornea's shape include rigid contact lenses, surgical implantation of stiff plastic intrastromal corneal ring segments, a collagen cross-linking procedure and, in severe cases, cornea transplantation. The collagen cross-linking procedure involves topical application of a concentrated riboflavin (vitamin B2) solution after the corneal epithelium is scraped, followed by ultraviolet (UV) light exposure. UV light stimulates riboflavin to form new bonds (cross links) between the cornea's connective tissue, giving the cornea additional strength to maintain its shape and prevent the need for transplantation. The cost of one treatment using this system is $2,500 to $3,500. A small prospective study including 7 patients with keratoconus was started on a trial of oral riboflavin and 15 minutes of natural sunlight exposure daily. These patients reported no adverse effects and preliminary results showed corneal stabilization and/or corneal flattening in all 7 patients It is hypothesized that dietary riboflavin and natural sunlight is as effective in corneal crosslinking as the currently FDA approved Avedro therapy. If the clinical study confirms the investigators' early observations of the benefits of this approach, coupled with animal studies that document corneal cross-linking, the investigators will have data to pursue funding for larger clinical and animal studies. This has the potential to save millions of dollars in health care costs and ease the burden of treatment in patients who require therapy to induce corneal cross-linking to stabilize the cornea's shape.
Corneal ectasia as a complication from refractive (LASIK) surgery as well as keratoconus is a slowly progressive condition that results in high patient morbidity. Treatment options aim to stabilize the shape of the cornea using rigid contact lenses, surgical insertion of stiff plastic intrastromal rings, corneal cross linking, and ultimately corneal transplant in severe patients. The recently FDA approved "Dresden Protocol" involves painful cornea scraping followed by application of concentrated Riboflavin, followed by immediate collagen cross linking with UV light exposure which results in shortening and thickening of the collagen fibrils, and therefore a stronger, stiffer cornea. Avedro has demonstrated an average cornea flattening (K max reduction) of 1.4 diopters and 1.7diopters in two different studies. The current cost of Avedro therapy is between $2500 -$3500 per treatment. This is considered experimental at this time and therefore is not covered by any insurance.To spare the patient the severe pain involved in the current procedure, and to avoid the high cost (Avedro is not covered by any medical insurance), the investigator started 7 patients with keratoconus from 2011-2015 in his private practice in Seattle on a trial of oral riboflavin (100 mg or 400 mg daily) and 15 minutes of sunlight exposure daily. No adverse effects have ever been reported with high-dose dietary riboflavin supplements. The results of this preliminary trial are remarkable. During follow-up from 6 months to 5 years, all 7 patients have had corneal stabilization and/or corneal flattening. One patient experienced flattening of the cornea by 1.5 Diopters, comparable to the best results of the Avedro system. A limited animal study is currently underway to document that corneal cross-linking occurs in response to dietary riboflavin and UV exposure from the sun. This clinical study would expand the promising preliminary findings to a larger sample size. This has the potential to save millions of dollars in health care costs and ease the burden of treatment in patients who require therapy to induce corneal cross-linking to stabilize the cornea's shape.
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University of Missouri-Columbia
Published on BioPortfolio: 2017-03-30T00:08:22-0400
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 t...
Prospective, randomized, single site to determine the safety and effectiveness of performing corneal collagen cross-linking (CXL) using riboflavin and UVA light in eyes progressive keratoc...
Cross-linking of the cornea increases the mechanical and biochemical stability of the stromal tissue. The purpose of this study is to assess the effectiveness of riboflavin-ultraviolet lig...
To evaluate two different techniques of cross linking: standard epithelium off (CXL epi off) versus trans-epithelial (CXL epi on) cross linking in patient with progressive keratoconus.
The objectives of this study are to evaluate the safety of and efficacy of the KXL system with vibeX Rapid (Riboflavin Ophthalmic Solution) for Corneal Collagen Cross-Linking in eyes havin...
Lucigenin-riboflavin chemiluminescence is reported for the first time. Moreover, most dopamine chemiluminescence (CL) detection methods are based on the quenching of CL by dopamine. In contrast, we fi...
Thiamin, riboflavin and pyridoxal phosphate (PLP) concentrations are useful indices for evaluating vitamin B, B and B status. Several HPLC assays have been developed for determining thiamin, riboflavi...
Microemulsions are widely studied as potential ocular drug delivery vehicles. In the present study we show the versatility of possible use microemulsions as ocular delivery vehicle. The ME is loaded w...
The overproduction of riboflavin (vitamin B2) by Ashbya gossypii, one of the most distinctive traits of this filamentous hemiascomycete, has been proposed to act as an ecological defense mechanism, si...
Older adults have potential increased risk of nutrient deficiencies due to age-related decreased dietary intake and malabsorption; it is important to ensure nutrient needs are met to avoid adverse hea...
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)
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 18.104.22.168.
Iron or iron compounds used in foods or as food. Dietary iron is important in oxygen transport and the synthesis of the iron-porphyrin proteins hemoglobin, myoglobin, cytochromes, and cytochrome oxidase. Insufficient amounts of dietary iron can lead to iron-deficiency anemia.
Phosphorus used in foods or obtained from food. This element is a major intracellular component which plays an important role in many biochemical pathways relating to normal physiological functions. High concentrations of dietary phosphorus can cause nephrocalcinosis which is associated with impaired kidney function. Low concentrations of dietary phosphorus cause an increase in calcitriol in the blood and osteoporosis.
Dietary recommendations that promote reduction in or prevention of high blood pressure. Recommendations include increasing intake of fruits and vegetables, and high-fiber, low-fat foods and reducing the intake of DIETARY SODIUM and high fat foods.
Ophthalmology is the branch of medicine that is devoted to the study and treatment of eye diseases. As well as mild visual defects correctable by lenses, ophthalmology is concerned with glaucoma, uveitis and other serious conditions affecting the eye, ...
Surgery is a technology consisting of a physical intervention on tissues. All forms of surgery are considered invasive procedures; so-called "noninvasive surgery" usually refers to an excision that does not penetrate the structure being exci...