To the Editor.

Present understanding of the pathogenesis of retinopathy of prematurity (ROP) can be summarized in describing preproliferative and proliferative stages of the disease process. The preproliferative stages probably involve actual or relative hyperoxic and perhaps hypoxic and ischemic injury of and hypercarbia-induced barotrauma to immature retinal capillaries, resulting in shunt formation. An arrest in peripheral retinal vessel development occurs. The inner portion of the peripheral avascular retina (PAR), presumably attributable to an oxygen deficit, begins to elaborate factors that promote neovasculogenesis, thus ushering in . . . [Full Text of this Article]