Retinitis pigmentosa is a genetic condition which begins with night blindness and progresses to decreased peripheral vision followed by complete loss of vision. This condition mainly affects the rods in the retina. The classic triad of waxy pale optic disc, attenuated blood vessels and pigmented spicules can be observed when the retina is examined via ophthalmoscope. Pigment spicules represent the retinal pigment epithelial cells which track along retinal vessels.
Image via: https://www.pinterest.co.uk/pin/490962796854643293/