has part has part has modifier Rod-cone dystrophy Retinitis pigmentosa is a group of hereditary diseases of the eye. However, the term retinitis pigmentosa has also been used to describe the retinal findings characteristic of these diseases but also seen on other diseases such as Usher syndrome. It is preferable to describe the findings precisely if possible, but this term is kept for convenience. Retinal degeneration Retinal dystrophy Retinal atrophy quality abnormal