As a result of advances in technology, particularly in life support systems capable of keeping tiny premature infants alive, and better observation of the premature infant fundus with improved ophthalmoscopic tehniques, including the indirect ophthalmoscope, much has been learned about the early active stages of retinopathy of prematurity (ROP). This term is preferred because it can be utilized to describe all phases of the retinal changes observed in premature infants. The traditional term, retrolental fibroplasia, is inappropriate in the acute phase of this disorder, for it describes solely those later cicatricial changes which involve the eyes of only the most severely affected infants. Much of what has been learned over the past two decades about the disease in its modern form fails to fit with the Reese classification system,1 or any other classification system extant. Furthermore, the real incidence of the disease may be increasing although the evidence on this point is inconclusive and treatment of the disease in its active and cicatricial form has been advocated but it is not always clear wht disease stage is being treated and what the results of such treatment are. Hence, the need for a new classification system of the acute stages of ROP at this time, with a classification of the cicatricial stages to follow.
The system presented here differs from previous systems in that it permits the examiner to specify at the outset two parameters of the disease not recognized in other classification systems. These are the location of the disease in the retina and the extent of the developing vasculature involved.