Age-related macular degeneration

Abstract

Age-related macular degeneration (AMD) is the leading cause of irreversible severe visual loss in the United States in people over 50 years of age. The nonexudative stage includes hard drusen (associated with localized dysfunction of the retinal pigment epithelium [RPE]), soft drusen (associated with diffuse dysfunction of the RPE), and geographic (areolar) atrophy. These fundus changes may predispose the eye to develop the neovascular/exudative stages of AMD. Most patients who develop severe visual loss from AMD have this exudative stage. Treatment for AMD has been shown to be effective for only a small proportion of patients who have a well-defined choroidal neovascular membrane (CNVM) more than 200 microns from the foveal center. Even in successfully treated cases, severe visual loss is postponed only for about 18 months because of the high rate of recurrent CNVMs that extend into the fovea. Thus, despite recent breakthroughs in laser treatment for AMD, most patients who develop the exudative form of AMD will develop central visual impairment. At the present time, the only available treatments for the majority of patients who develop the exudative form of AMD are low vision aids. Investigators are currently evaluating whether treatment is effective for membranes within 200 microns of the foveal center. Future studies need to be directed toward further understanding of the pathogenesis, treatment and prevention of the blinding complications of AMD.

Pars plana vitrectomy for regression of choroidal neovascularization with age‐related macular degeneration

“…Subretinal exudates also decreased in 8 eyes. Spontaneous regression has been reported to occur in approximately 20% of patients with ARMD (Bressler et al 1988a(Bressler et al , 1988bPoliner et al 1986;Chandra et al 1974), so the outcome of the clinical series reported here is clearly better compared to the natural progression of the disease. The patients in our study who showed regression or complete disappearance of CNV had relatively small size and little involvement of the macula and CNV within one-half the optic disk diameter from the foveola.…”

Plasma homocysteine and total thiol content in patients with exudative age-related macular degeneration

“…13 Pathogenesis of choroidal neovascularization in ARMD involves a complex interplay of environmental, biochemical changes, and genetic predisposition. 14 Hcys has been shown to undergo autoxidation in the presence of transition metal ions like iron which culminates in the generation of hydroxyl radical (OH K ).…”

Contrast sensitivity as an outcome measure in patients with subfoveal choroidal neovascularisation due to age-related macular degeneration

“…8 The majority of patients with severe vision loss (defined as a loss of 6 or more lines of visual acuity) due to AMD have the neovascular form of the condition, which is characterised by choroidal neovascularisation (CNV). 9,10 Vision loss is more likely to be severe in patients with lesions that lie under the foveal avascular zone (subfoveal lesions) than in those that lie outside the fovea. New treatment modalities, such as photodynamic therapy with verteporfin (Visudyne s , Novartis Pharma AG, Basel, Switzerland), have increased the range of treatments available for patients with subfoveal CNV due to AMD.…”