Two assessment visits will be conducted in order to evaluate functional visual performance in severely vision impaired subjects with RP and normally sighted subjects. Two visits will occur at week 0 and week 4 with functional vision assessments occurring at both visits in order to assess visit-to-visit variability. For the MLYMT, navigational vision will be assessed using each eye and binocularly at up to 6 different light levels (range 0.3 to 100 lux). Subjects will also perform the Multi-Luminance Shape Discrimination Test (MLSDT) which assesses near object recognition under different lighting levels. MLYMT and MLSDT performance will be evaluated together with Best Corrected Visual Acuity (BCVA), Visual Field (VF) and responses to visual function questionnaires. Subjects will be assigned to one of two cohorts based on presence or absence of RP in addition to BCVA performance.
This is a prospective Multi-Center Observational Study to assess the reliability and validity of the Multi-Luminance Y-Mobility Test (MLYMT). Main Outcome Measures: (i) Performance scores in normal and severely visually impaired subjects with a clinical diagnosis of retinitis pigmentosa (RP) on MLYMT at multiple luminance levels and (ii) reliability and content validity of MLYMT.