Correlations between electroretinography, morphology and function in retinitis pigmentosa

In a retrospective study, data from 116 patients suffering from different forms of retinitis pigmentosa were analysed, and 15 categories comprising altogether 34 symptoms or clinical signs were tabulated from each patient's record. The 15 categories evaluated were: visual acuity, visual field diameter, ring or central scotoma, nyctalopia, susceptibility to glare, refraction, cataract, electroretinography, colour of the optic disc, bone-spicule pigmentation of the retina, retinal vessel diameters, tapetoretinal reflex, sex, heredity, and age. Correlations between the tabulated 34 subcategories or symptoms were calculated. The results of a factorial analysis of the data showed a high number of highly significant correlations between the different categories. It seemed possible to discriminate between two groups of categories, with the members of each group being closely correlated but correlations with members of the other group being much smaller, if not nonexistent. We tentatively associated the first group with the functional state of the central retina and the second group with the state of the peripheral retina.