[Pathogenesis of lesions in late age-related macular disease]

To summarize the evidence that exists concerning the pathogenesis of lesions in late age-related macular disease (AMD), we reviewed both experimental evidence and clinical observations that address these problems. There is good evidence that choroidal neovascularization is due to a change in the balance of growth factors derived from the retinal pigment epithelial basolateral plasma membrane domain (RPE). Retinal angiomatous proliferation may also have a similar pathogenesis involving the apical domain. Detachment of the RPE is likely to be a consequence of increased resistance of Bruch's membrane to water flow due to deposition of lipids. Geographic atrophy is preceded by accumulation of autofluorescent material in the RPE and possible causal relationships between the two have been demonstrated. There is increasing understanding concerning the sequence of events that lead to those lesions causing loss of central vision in AMD. Therapeutic approaches that address the underlying mechanisms are more likely to succeed than current treatment options. Such an approach has already been initiated in the management of choroidal neovascularization.