Retinopathy of Prematurity: History, Classification, and Pathophysiology

Abstract

After completing this article, readers should be able to: 1. Describe the onset of retinopathy of prematurity (ROP). 2. Explain the role of oxygen in ROP. 3. Compare and contrast zones I, II, and III disease. 4. Describe the stages of ROP. 5. Characterize “plus” disease. 6. Describe the infants in whom severe ROP leading to the need for surgery is common. 7. Describe the timeframe at which ROP is visible in the eye. ### The First ROP In 1942, Terry described the first infant who had grey, blood vessel-covered membranes behind the pupil. As more cases were described, the name retrolental fibroplasia (RLF) was coined (Fig. 1⇓ ). Distressingly, it became common around the world in special units for preterm infants. Pathologic specimens were rare (Fig. 2⇓ ) , but serial examinations of preterm infants following birth revealed that infants were not born with RLF; they developed it after birth. By the end of the 1940s, many innovations in the new preterm infant nurseries had been implicated, some were exonerated, and it was time to examine the role of oxygen. Figure 1. End-stage ROP. The white pupils (leukocoria) of stage 5 ROP result from total retinal detachment, with the mass of fibrous neovascularization and the retina pushing up against the lens from behind. This is the source of the historical name retrolental fibroplasia. Photograph courtesy of A. Patz, MD, used with permission. Reprinted with permission from Pediatrics . 1957;19:502–504. Figure 2. A. Artist’s rendering of stage 5 retinal detachment. B. Pathologic specimen of an eye with stage 5 ROP. In this cross section, the lens is displaced into the anterior chamber by the mass of tissue in the vitreous composed of the detached retina and the large number of extraretinal vessels and accompanying scar tissue (fibroplasia). The retina remains attached at the posterior pole at the optic disc and around the rim …