The purpose of this article is to complete the classification of retinopathy of prematurity (ROP) begun with the publication of the recent article on the subject entitled, "An International Classification of Retinopathy of Prematurity" (ICROP).1-3 The previously published classification embodied three major concepts for the description of the early phases of the disease: specifying its location by zones of retinal involvement; recording the extent of retinal involvement by clock hours; and, finally, staging the disease according to the degree of vascular lesions observed (stages 1 through 4). That article specified posterior dilatation and tortuosity of retinal vessels as ominous prognostic signs. The committee that authored it left unclassified the sequelae that encompass the cicatricial phase of the disease. It recommended the use of the Reese classification4 until a more satisfactory one could be developed.
The reasons for completing the classification of the end stages of ROP at this time are compelling. First, there has been an increase in the survival rate of infants of low birth weight who are most likely to develop the severe forms of the disease. Second, surgical treatment of these blind or nearblind infants is being undertaken without knowing which stage is being treated and what the implications of the results of such treatment are. Finally, as a result of further surgical observations and study of pathologic specimens, we now have an increased understanding of the development of the severe end stages of ROP.
The system presented herein elaborates the features of the retinal detachment (stage 4) of the international classification.