On the basis of this mathematical model, VEGF Trap maintains significant intravitreal VEGF-binding activity for 10-12 weeks after a single injection.
Vascular endothelial growth factor (VEGF) plays an important role in both physiologic and pathologic angiogenesis and contributes to increased permeability across both the blood-retinal and blood-brain barriers. After 2 decades of extensive research into the VEGF families and receptors, specific molecules have been targeted for drug development, and several medications have received US Food and Drug Administration approval. Bevacizumab, a full-length antibody against VEGF approved for the intravenous treatment of advanced carcinomas, has been used extensively in ophthalmology for exudative age-related macular degeneration, diabetic retinopathy, retinal vein occlusions, retinopathy of prematurity, and other chorioretinal vascular disorders. Pegaptanib and ranibizumab have been developed specifically for intraocular use, whereas the soon-to-be-introduced aflibercept (VEGF Trap-Eye) is moving through clinical trials for both intraocular and systemic use. Although these drugs exhibit excellent safety profiles, ocular and systemic complications, particularly thromboembolic events, remain a concern in patients receiving therapy. Patients experiencing adverse events that may be related to VEGF suppression should be carefully evaluated by both the ophthalmologist and the medical physician to reassess the need for intraocular therapy and explore the feasibility of changing medications. For this review a search of PubMed from January 1, 1985 through April 15, 2011, was performed using the following terms (or combination of terms): vascular endothelial growth factors, VEGF, age-related macular degeneration, diabetic retinopathy, retina vein occlusions, retinopathy of prematurity, intravitreal injections, bevacizumab, ranibizumab, and VEGF Trap. Studies were limited to those published in English. Other articles were identified from bibliographies of retrieved articles and archives of the author.
Cytomegalovirus (CMV) retinitis is the most common cause of vision loss in patients with acquired immunodeficiency syndrome (AIDS). CMV retinitis afflicted 25% to 42% of AIDS patients in the pre-highly active antiretroviral therapy (HAART) era, with most vision loss due to macula-involving retinitis or retinal detachment. The introduction of HAART significantly decreased the incidence and severity of CMV retinitis. Optimal treatment of CMV retinitis requires a thorough evaluation of the patient’s immune status and an accurate classification of the retinal lesions. When retinitis is diagnosed, HAART therapy should be started or improved, and anti-CMV therapy with oral valganciclovir, intravenous ganciclovir, foscarnet, or cidofovir should be administered. Selected patients, especially those with zone 1 retinitis, may receive intravitreal drug injections or surgical implantation of a sustained-release ganciclovir reservoir. Effective anti-CMV therapy coupled with HAART significantly decreases the incidence of vision loss and improves patient survival. Immune recovery uveitis and retinal detachments are important causes of moderate to severe loss of vision. Compared with the early years of the AIDS epidemic, the treatment emphasis in the post- HAART era has changed from short-term control of retinitis to long-term preservation of vision. Developing countries face shortages of health care professionals and inadequate supplies of anti-CMV and anti-HIV medications. Intravitreal ganciclovir injections may be the most cost effective strategy to treat CMV retinitis in these areas.
Diabetic retinopathy (DR) is the leading cause of blindness in industrialized countries. Remarkable advances in the diagnosis and treatment of DR have been made during the past 30 years, but several important management questions and treatment deficiencies remain unanswered. The global diabetes epidemic threatens to overwhelm resources and increase the incidence of blindness, necessitating the development of innovative programs to diagnose and treat patients. The introduction and rapid adoption of intravitreal pharmacologic agents, particularly drugs that block the actions of vascular endothelial growth factor (VEGF) and corticosteroids, have changed the goal of DR treatment from stabilization of vision to improvement. Anti-VEGF injections improve visual acuity in patients with diabetic macular edema (DME) from 8-12 letters and improvements with corticosteroids are only slightly less. Unfortunately, a third of patients have an incomplete response to anti-VEGF therapy, but the best second-line therapy remains unknown. Current first-line therapy requires monthly visits and injections; longer acting therapies are needed to free up healthcare resources and improve patient compliance. VEGF suppression may be as effective as panretinal photocoagulation (PRP) for proliferative diabetic retinopathy, but more studies are needed before PRP is abandoned. For over 30 years laser was the mainstay for the treatment of DME, but recent studies question its role in the pharmacologic era. Aggressive treatment improves vision in most patients, but many still do not achieve reading and driving vision. New drugs are needed to add to gains achieved with available therapies.
Purpose To comprehensively review the literature regarding recurrent corneal erosion (RCE) and to present treatment options and recommendations for management. Overview RCE usually presents with sharp, unilateral pain upon awakening, in an eye with an underlying basement membrane dystrophy, prior ocular trauma, stromal dystrophy or degeneration, or prior surgery for refractive errors, cataracts, or corneal transplantation. Making the correct diagnosis requires a careful slit-lamp examination of both eyes coupled with a high degree of suspicion. Several treatments are commonly used for RCE but new therapies have been introduced recently. Conservative treatment consists of antibiotic and preservative-free lubricating drops, with topical cycloplegics and oral analgesics to control pain. Patients who are unresponsive to these therapies may benefit from therapeutic bandage contact lenses (BCL). Newer therapies include oral matrix metalloproteinase (MMP) inhibitors, blood-derived eye drops, amniotic membrane graft application, and judicious application of topical corticosteroids. Once the epithelium is healed, a course of hypertonic saline solution and/or ointment can be used. Surgical procedures may be performed in patients who fail conservative therapy. Punctal occlusion with plugs increases the tear film volume. Epithelial debridement with diamond burr polishing (DBP), anterior stromal puncture (ASP), or alcohol delamination should be considered in selected patients. DBP can be used for patients with basement membrane dystrophies and is the preferred treatment overall due to a low recurrence rate. ASP can be used for erosions outside the central visual axis. Excimer laser phototherapeutic keratectomy is an attractive option in eyes with central RCE since it precisely removes tissue while preserving corneal transparency. In patients with RCE who are also candidates for refractive surgery, photorefractive keratectomy can be considered. Summary Newly introduced therapies for RCE enable therapy to be individualized and lower the recurrence rate.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.