Retinitis pigmentosa represents a heterogeneous group of degenerative hereditary pathologies of the retinal photoceptors, some forms mainly affect the cones and others the rods. The prevalence of the disease is of 1 case per 3000-5000 inhabitants, in 80-90% of cases these are forms with prevalent involvement of the rods (RCD) and in 10-20% of cases of forms with prevalent involvement of the cones (CRD) [...].