Swinging flashlight test[2] - when the pupil exhibits an RAPD, it is described as a Marcus Gunn pupil. It suggests optic nerve disease, central retinal artery or vein occlusions (see the separate article on Non-diabetic Retinal Vascular Disease). A mild RAPD may also occur in amblyopia, with vitreous haemorrhage, retinal detachment or advanced macular degeneration.