Page 80 - NAME OF CONDITION: REFRACTIVE ERRORS

NAME OF CONDITION: AGE RELATED MACULAR

DEGENERATION (AMD)

I. WHEN TO SUSPECT/ RECOGNIZE?

a) Introduction:

Age related macular degeneration (AMD) is one of the leading causes of low vision in
developed countries. However, this condition is being increasingly recognized in our
country in recent times. It has been found to have significant impact on the
individual’s quality of life. As the geriatric population of the country increases,
courtesy of improved medical services, the number of people afflicted with AMD will
proportionately, increase. Understanding the epidemiology, risk factors and
treatment modalities of AMD is essential to improve the overall ocular health of the
individual.

b) Case definition:
Age-related macular degeneration is defined as a degenerative disease
characterized by the presence of the following: drusen; retinal pigment epithelium
(RPE) abnormalities; RPE and associated neurosensory detachment; retinal
haemorrhages; choroidal neovascularization; geographic atrophy, or retinal fibrous

scarring in the absence of other retinal disorders.
 Drusen are localized, discrete whitish-yellow deposits lying between the
basement membrane of the RPE and Bruch’s membrane.
 Abnormalities of the RPE include hyperpigmentation or hypopigmentation,
without any visibility of the choroidal vessels as associated with drusen.
 Geographic atrophy is defined as sharply delineated, confluent areas of
hypopigmentation or depigmentation or apparent absence of the RPE in which
choroidal vessels are more visible than in surrounding areas.

 Choroidal neovascularization is the growth of new blood vessels from the
choroid, characterized morphologically by greenishgrey subretinal tissue, with
or without subretinal haemorrhage or exudates.
 Dry AMD is defined as the presence of drusen and RPE abnormalities, including
geographic atrophy.
 Wet AMD is defined as the presence of any of the following: RPE detachments

or serous detachment of the sensory retina; subretinal or sub-RPE neovascular
membranes; subretinal haemorrhages, and epiretinal, subretinal, intraretinal
or sub-pigment epithelial scar or glial tissue or fibrin-like deposits.
Several classification systems have evolved over the years to define this entity and
describe the various stages. The commonest ones used in epidemiological studies is

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