What is the hallmark characteristic of wet AMD?

The hallmark characteristic of wet age-related macular degeneration (AMD) is choroidal neovascularization (CNV). This process involves the growth of abnormal blood vessels from the choroid layer beneath the retina into the subretinal space, which is often associated with significant vision loss. These newly formed vessels are fragile and can leak fluid and blood, leading to complications such as swelling and scarring in the retina.

While drusen formation and macular edema are features that can be associated with AMD, particularly in its dry form or as a result of CNV, they do not define wet AMD specifically. In contrast, retinal thinning may occur as a consequence of retinal damage over time but is not a defining characteristic of wet AMD. Thus, the presence of CNV is what distinguishes wet AMD from other forms of macular degeneration and is critical for diagnosis and treatment decisions.