**4. Classification of AMD**

358 Lipoproteins – Role in Health and Diseases

Life Expectancy (years)

60

65

70

75

80

85

90

**Figure 2.** Male and female life expectancy 1950-2050.

Projected figures for 2028 and 2050: USA data.

Males Females

\* Figures from 1950 and 2001: Irish Department of Health and Children data;

Male and Female Life Expectancy 1950-2050

Year 1940 1960 1980 2000 2020 2040 2060 In 1995, the International Age-Related Maculopathy Epidemiological Study Group clarified the definition and core grading system used to detect and define AMD.[27] This was done to homogenize the systems used to identify and classify this disease in all future clinical and epidemiological studies. This current classification system defines AMD primarily on the basis of morphological changes, without reference to visual acuity.

AMD is defined as a disorder of the macular area, most often clinically apparent after 50 years of age, and characterised by any of the following findings, which are not patently due to another disorder:


**Figure 4.** Macular soft drusen of a left eye.

These age-related pathological changes, which are associated with progressive accumulation of debris under the retina, predispose to the late stage of AMD.[28;29] Late AMD is classified as either geographic atrophy (atrophic AMD) or neovascular AMD (choroidal neovascularisation, also referred to as 'exudative AMD' or 'disciform AMD').

Geographic atrophy (GA) is characterised by the following, which is not patently due to another disorder:

1. Any sharply delineated area of hypopigmentation, or depigmentation, or apparent absence of the RPE, in which the choroidal vasculature is more visible than in the surrounding area. The area of atrophy must be ≥ 175 μm in diameter (Figure 5).

Neovascular AMD is characterised by any of the following, which are not patently due to another disorder:


**Figure 4.** Macular soft drusen of a left eye.

another disorder:

another disorder:

These age-related pathological changes, which are associated with progressive accumulation of debris under the retina, predispose to the late stage of AMD.[28;29] Late AMD is classified as either geographic atrophy (atrophic AMD) or neovascular AMD (choroidal

Geographic atrophy (GA) is characterised by the following, which is not patently due to

1. Any sharply delineated area of hypopigmentation, or depigmentation, or apparent absence of the RPE, in which the choroidal vasculature is more visible than in the

Neovascular AMD is characterised by any of the following, which are not patently due to

surrounding area. The area of atrophy must be ≥ 175 μm in diameter (Figure 5).

neovascularisation, also referred to as 'exudative AMD' or 'disciform AMD').

5. Hard exudates (lipids) within the macular area, related to any of the above, in the absence of other retinal vascular disease.

Rarely, neovascular AMD may develop in an area of GA. If this happens, the affected eye is re-classified as having neovascular AMD.

**Figure 5.** Geographic atrophy, affecting the entire macula of a right eye.

**Figure 6.** Neovascular AMD, showing sub-retinal haemorrhage in a left eye.
