Age-related macular degeneration

Potentially progressive maculopathy.

Sudden-onset of blurring or distortion of vision is often the presenting symptom.

Characterized by drusen formation, macular pigmentary changes, geographic atrophy, and neovascularization of the choriocapillaris with exudation.

Leading cause of adult blindness in industrialized nations.

Typically affects white people aged >55 years.

Diagnosis and treatment are highly specialized and involve consultation with a retinal specialist.

Age-related macular degeneration (AMD) is a potentially progressive maculopathy.[1]Arnold J. Age related macular degeneration. BMJ Clin Evid. February 2016. http://clinicalevidence.bmj.com/ (last accessed 26 September 2017). http://clinicalevidence.bmj.com/x/systematic-review/0701/overview.html It is characterized by distinct clinical stages including early and intermediate AMD with drusen and macular pigmentary changes, usually associated with normal or near-normal vision; and late AMD, which is associated with a decrease or loss of central vision. Late (or advanced) AMD has 2 forms: geographic atrophy (or “atrophic” or “dry” AMD) and neovascular AMD (or “wet” or "exudative” AMD).[2]Ferris FL 3rd, Wilkinson CP, Bird A, et al; Beckman Initiative for Macular Research Classification Committee. Clinical classification of age-related macular degeneration. Ophthalmology. 2013;120:844-851. http://www.ncbi.nlm.nih.gov/pubmed/23332590?tool=bestpractice.com

Subjects with small drusen (<63 micrometers), also termed drupelets, are considered to have normal aging changes. Subjects with medium-sized drusen (≥63 to <125 micrometers) in the absence of pigmentary changes are defined as having early AMD. Subjects with large drusen (≥125 micrometers) or pigmentary abnormalities and at least medium-sized drusen are defined as having intermediate AMD.

Five-year risks of progressing to late AMD are estimated to increase from 0.5% for normal aging changes up to 50% risk for intermediate AMD.

In addition, pseudodrusen are now recognized as precursors to both forms of late AMD.[3]Zhou Q, Daniel E, Maguire MG, et al. Pseudodrusen and incidence of late age-related macular degeneration in fellow eyes in the comparison of age-related macular degeneration treatments trials. Ophthalmology. 2016;123:1530-1540. http://www.aaojournal.org/article/S0161-6420(16)00330-4/fulltext http://www.ncbi.nlm.nih.gov/pubmed/27040149?tool=bestpractice.com [4]Suzuki M, Sato T, Spaide RF. Pseudodrusen subtypes as delineated by multimodal imaging of the fundus. Am J Ophthalmol. 2014;157:1005-1012. http://www.ncbi.nlm.nih.gov/pubmed/24503406?tool=bestpractice.com