Recent advances in the treatment of age-related macular degeneration

Abstract

Loss of central vision with age-related macular degeneration (ARMD) is a devastating reality for 8% of adults aged over 65 years in the UK,1 but new therapies with the potential to halt and improve visual loss have emerged. As a result, the NHS faces some difficult choices in terms of provision of and access to treatments. ARMD is thought to be a group of genetically- and environmentally-determined retinal degenerative diseases: in ARMD there is an age-related dysfunction of the retinal pigment epithelial cells, which are essential for photoreceptor metabolism and removal of waste products. Dysfunctional cells accumulate undigested waste, which is clinically evident as focal yellow subretinal clumps, termed drusen. Drusen are the herald of ARMD, and large or numerous drusen are poor prognostic factors for future visual loss.2 The disruption of photoreceptor metabolism eventually causes areas of retinal atrophy: the macula, the ‘high definition’ central point of the retina with the highest density of photoreceptors, is consequently more susceptible to this progressive dysfunction. In the majority of patients, ARMD occurs as atrophic or ‘dry’ macular degeneration. This is a relatively slow process, and at the present time there is no effective treatment. In the remaining patients with ‘wet’ or neovascular disease there is aberrant growth of choroidal blood vessels beneath the dysfunctional retina: haemorrhage and oedema from these neovascular membranes causes sudden central visual loss. Retinal angiography is needed to identify and classify the membranes as ‘classic’ well-defined lesions or amorphous ‘occult’ membranes, as the classification has an impact on the treatments available. A current estimate of the incidence of wet ARMD in the UK is around 21 000 new cases each year.3 Patients with ARMD who need referral to ophthalmic services present …