Retinitis Pigmentosa is associated with all except -

Systemic associations. These are in the form of following syndromes: 1. Laurence-Moon-Biedl syndrome. It is characterised by retinitis pigmentosa, obesity, hypogenitalism, polydactyly and mental deficiency. 2. Cockayne's syndrome. It comprises retinitis pigmentosa, progressive infantile deafness, dwarfism, mental retardation, nystagmus and ataxia. 3. Refsum's syndrome. It is characterised by retinitis pigmentosa, peripheral neuropathy and cerebellar ataxia. 4. Usher's syndrome. It includes retinitis pigmentosa and labyrinthine deafness. 5. Hallgren's syndrome. It comprises retinitis pigmentosa, vestibulo-cerebellar ataxia, congenital deafness and mental deficiency. Ref : comprehensive ophthalmology AK khurana 4/e page no 269 .