title: Assessment of visual distortions in age-related macular degeneration: emergence of new approaches.
abstract: With the arrival of effective treatments for neovascular age-related macular degeneration (nvAMD) there is a need to find improved tests that would allow early detection. Ideally, these tests would allow monitoring of vision by patients themselves from home. The aim of this review is to discuss the available evidence for two recently developed vision tests designed for this purpose: the Preferential Hyperacuity Perimeter (PHP) test and the Radial Shape Discrimination (RSD) test.
  
  
  
  Articles that investigated detection of nvAMD were reviewed. The methodology of the clinical evidence, where available, was judged for bias and applicability of the results to the general population using the QUADAS-2 quality assessment tool.
  
  
  
  The PHP test has proved to be good at detecting nvAMD but many studies assessed in this review were biased in the selection of patients, restricting the results to only those patients who can use the test and produce reliable results. On the other hand the RSD test is a simple test, well accepted by elderly patients with AMD. However, clinical studies to determine its value in the detection of early signs of nvAMD are still required.
  
  
  
  To date, more studies have investigated the utility of the PHP test compared with the RSD test for detection of nvAMD. Both tests show promise but further evidence is needed to determine the real generalisability of the PHP test and the sensitivity of the RSD test.
authors.affiliation: Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool.
authors.forename: Noelia
authors.initials: N
authors.lastname: Pitrelli Vazquez
authors.affiliation: Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool.
authors.forename: Paul C
authors.initials: PC
authors.lastname: Knox
keywords: Age-related macular degeneration; Preferential hyperacuity perimeter; Radial shape discrimination; Shape discrimination hyperacuity