RPGR and severe early-childhood-onset retinal dystrophy: Retinal sensitivity is better correlated to outer retinal thickness and therefore photoreceptor damage,[182] which is often demarcated by the hyper-AF macula ring, and severe peripheral VF defects can be seen in the absence of RPE loss and marked hypo-AF.[183] Other studies found female carriers of X-linked RP with RPGR mutations to demonstrate variable radial FAF patterns that can extend to the periphery.[184,185] An inferonasal boundary of abnormal FAF patterns may be noted in patients with RP or STGD and is thought to be related to closure of the optic fissure.[186]