About retinitis pigmentosa all are true, EXCEPT:

In retinitis pigmentosa rods are involved first followed by cones. As the disease progresses there is loss of night vision and peripheral field of vision. Only in the later stages of the disese there is loss of central vision. Retinitis Pigmentosa is a group of hereditary retinal degenerative disorder characterized by progressive dysfunction of photoreceptors, associated with progressive cell loss and atrophy of several retinal layers. Hallmark symptoms are: night blindness, progressive loss of peripheral field of vision and coalescing ring scotomas. Characteristic fundoscopic findings are: attenuated retinal aerioles, waxy pale optic disc, mottling of retinal pigment epithelium, and peripheral retinal pigment clumping (bone spicule formation). ERG shows reduced/absent retinal function. EOG lacks usual light rise.