If excess oxygen is given, normal blood vessels degrade and cease to develop. The normal growth of the blood vessels is directed to relatively low-oxygen areas of the retina, but the vessels remain in the plane of the retina and do not grow into the vitreous humor. Normally, maturation of the retina proceeds in utero, and at term, the medial portion (Nasal retina) of the retina is fully vascularized, while the lateral portion (Temporal retina) is only incompletely vascularized. When the blood and abnormal vessels are reabsorbed, it may give rise to multiple band like membranes which can pull up the retina, causing detachment of the retina and eventually blindness before 6 months. These abnormal blood vessels may grow up from the plane of the retina and may bleed inside the eye. If the vessels grow and branch abnormally the baby develops ROP. If blood vessels grow normally, ROP does not occur. However, in premature babies it is incomplete. This process is completed a few weeks before the normal time of delivery. They are:ĭuring development, blood vessels grow from the central part of the retina outwards. Various risk factors contribute to the development of ROP. In rare cases ROP has been found in some patients with a mutation in the NDP gene, which is normally associated with the more damaging Norrie disease. Such formation of blood vessels appears to be very sensitive to the amount of oxygen supplied, either naturally or artificially. Both oxygen toxicity and relative hypoxia can contribute to the development of ROP.īy the fourth month of pregnancy, the fetal retina has begun to develop vascularization. Thus, all preterm babies are at risk for ROP, and very low birth-weight is an additional risk factor. ROP can be mild and may resolve spontaneously, but it may lead to blindness in serious cases. It is thought to be caused by disorganized growth of retinal blood vessels which may result in scarring and retinal detachment. Retinopathy of prematurity ( ROP), also called retrolental fibroplasia ( RLF) and Terry syndrome, is a disease of the eye affecting prematurely born babies generally having received neonatal intensive care, in which oxygen therapy is used due to the premature development of their lungs. Terry syndrome, retrolental fibroplasia (RLF) Send us feedback about these examples.Medical condition Retinopathy of prematurity These examples are programmatically compiled from various online sources to illustrate current usage of the word 'retinitis.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Bryce Alderton, Daily Pilot, 20 June 2017 The two most common kinds of retina disorders are retinitis pigmentosa and macular degeneration, which together affect about more than 20 million Americans. Candy Sagon, charlotteobserver, 9 June 2017 Andrei was afflicted with a retinal degenerative disease known as retinitis pigmentosa, which can cause vision impairment or vision loss. 2017 The Argus II, a bionic retina approved by the Food and Drug Administration, is now being used by more than 100 people with retinitis pigmentosa and other related conditions. Recent Examples on the Web Chaudhri suffers from retinitis pigmentosa, which causes degeneration of the retina.
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