An international panel of retina specialists, imaging experts and ocular pathologists has developed the framework of a consensus nomenclature system for defining AMD, which also delineates the subtypes of wet AMD. The team believes establishing a uniform set of definitions will support comparison of diverse patient groups and different studies. Using the proposed classification and terminology, they argue, will improve standardization of AMD investigation and reporting.

The consensus team defined AMD as “a process by which the structure and function of the macula deteriorates over time in association with distinguishing signs and symptoms that typically become clinically evident past 50 years of age and do not appear to be secondary to other processes such as pathologic myopia, central serous chorioretinopathy, monogenetic inherited retinal disease, chorioretinal uveitic syndromes or infections or trauma.” They also stated that late phases of the disease include atrophy of the outer retina, thinning and loss of the retinal epithelial epithium (RPE) and macular neovascularization.

Neovascular disease can lead to leakage, bleeding, scarring and severe vision loss. The panel categorized macular neovascularization into three subtypes: polypoidal choroidal vasculopathy/Type 1, Type 2 and Type 3. The anatomic location of the neovascularization determined by OCT imaging is used to subclassify the vascular component of the disease process. According to the study group, Type 3 neovascularization is to be used when the vascular complex originates in the retina, Type 2 is used if neovascularization that originates in the choroid breaks through the RPE to reach the subretinal space, while Type 1 is applied when the vessels originate from the choroid and remains under the RPE.

The study group suggests that the consensus standards outlined in this manuscript be used in future AMD studies as well as clinical practice.

The panel also determined that using OCT and OCT angiography does not replace fluorescein angiography or color photography; rather, these additional forms of imaging provide additional data to improve classification.