[Retinopathy of prematurity and the "immaturity index"].
GOAL: To find an index which enables one to differentiate any high risk premature newborn of developing a retinopathy of prematurity. METHOD: Two groups of newborn are studied: 1) all the children under 2550 g at birth time and born between january 1979 and september 1987 and having had a diagnosis of retinopathy of prematurity, 2) all the children who were examined by the author from october 1987 to july 1990. RESULTS: 33 of the 118 children studied suffered from a retinopathy of prematurity. Small gestational age and weight is considered to be high risk as well as the association with necrotizing colitis, intracranial hemorrhage, hyaline membrane disease and/or bronchopulmonary dysplasia, oxygen therapy and sepsis. For all these factors studied p is less than 0.0001. We utilized the multiple regression coefficients to define the "Immaturity Index". CONCLUSION: The index is very specific in defining any child with no risk of developing the disease. It has a sensitivity of 0.9 in detecting any newborn suffering from a retinopathy over grade 2. It is much more powerful than any biological variable (gestational age or weight, oxygen therapy time) in predicting retinopathies (60%).