**red reflex** is the reddish-orange reflection of light from the back of the eye (fundus) observed when using an ophthalmoscope or retinoscope. similar to the "red eye" in flash photography. - relies on the transparency of optical media (tear, cornea, aqueous humor, lens, vitreous humor) and reflects off the fundus back through the media into the aperture of the ophthalmoscope - the red reflex is ==considered abnormal if it is missing== due to opacity at the cornea, anterior chamber, lens and vitreous, or if the retina is detached. - there is any asymmetry between the eyes - dark spots - white reflex (leukocoria) **causes of abnormal red reflex** - [[Retinal detachment]] - [[Central retinal vein occlusion]] - congenital cataract - retinoblastoma