Evolution of the visual prognosis of prematures in the last 20 years.

Ophthalmoscopic examinations were performed on 5678 prematures, born between 1964 and 1984, by the same investigator in the same neonatal care unit. Three periods can be differentiated. In the first period (1964-1970) retinal disorders were frequent (20%), a quarter of them severe (stages 3-5). The inspiratory fraction of oxygen was the only oxymetric factor that was monitored. In the second period (1970-1977), less severe forms were observed, but still 4.5% of stage 1 and 8.7% of stage 2 (mild forms) were assessed. During this period, oxygen partial pressure was measured every 6 h in arterial blood whenever the inspiratory fraction of oxygen exceeded 0.3. In the last period (1977-1984), no severe forms were observed and mild forms amounted to only 0.9%. In this period, oxygen partial pressure was continuously monitored transcutaneously, whenever the inspiratory fraction of oxygen exceeded 0.21. Such data show that there is an association between better oxygen monitoring and the dramatically reduced incidence of retinopathy in prematures (RP).