retinitis pig·men·to·sa -.pig-mən-'tō-sə, -(.)men-, -zə n any of several hereditary progressive degenerative diseases of the eye marked by night blindness in the early stages, atrophy and pigment changes in the retina, constriction of the visual field, and eventual blindness abbr. RP called also pigmentary retinopathy
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a hereditary condition characterized by progressive degeneration of the retina due to malfunctioning of the retinal pigment epithelium. It starts in childhood with night blindness and limited peripheral vision and may progress to complete loss of vision.
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a group of diseases, frequently hereditary, marked by progressive loss of retinal response (as elicited by the electroretinogram), retinal atrophy, attenuation of the retinal vessels, and clumping of the pigment, with contraction of the field of vision. It may be transmitted as a dominant, recessive, or X-linked trait and is sometimes associated with other genetic defects.Medical dictionary. 2011.