Retrolental fibroplasia

The use of oxygen in pediatric incubators is an important factor in increasing the survival rate of premature infants who develop cyanosis. However, the use of oxygen is associated with risk of developing the visual defect known as retrolental fibroplasia (38). A careflil monitoring of arterial blood oxygen partial pressure is important. 

As soon as it was appreciated that oxygen toxicity was somehow involved in retrolental fibroplasia, antioxidant administration was empirically investigated in both animal models and babies. In 1949, Owens and Owens reported a protective effect of vitamin E unfortunately this could not be substantiated in subsequent controlled trials. Phelps and Rosenbaum (1977) investigated whether vitamin E supplementation would influence oxygen-induced retinopathy in kittens and found it to be beneficial in reducing the severity of the lesions. Nevertheless, vitamin E has not yet been used with much success in preterm babies. 

Ashton, N., Ward, B. and Serpell, G. (1953). Role of oxygen in the genesis of retrolental fibroplasia preliminary report. Br. J. Ophthalmol. 37, 513-520. 

Flower, R.W. and Patz, A. (1971). Oxygen studies in retrolental fibroplasia. IX. The effects of elevated arterial oxygen tension on retinal vascular dynamics in the kitten. Arch. Ophthamol. 85, 197-208. 

Shahinian, L. and Malachowski, N. (1978). Retrolental fibroplasia a new analysis of risk factors based on recent cases. Arch. Ophthalmol. 96, 70-74. 

Silverman, W. (1980). Retrolental fibroplasia a modem parable. Fmne and Stratton, New York. 

Slater, T.F. and Riley, P.A. (1970). Free-radical damage in retrolental fibroplasia. Lancet ii, 467. 

Vitamin E may be indicated in some rare forms of anemia such as macrocytic, megaloblastic anemia observed in children with severe malnutrition and the hemolytic anemia seen in premature infants on a diet rich in polyunsaturated fatty acids. Also anemia s in malabsorption syndromes have shown to be responsive to vitamin E treatment. Finally, hemolysis in patients with the acanthocytosis syndrome, a rare genetic disorder where there is a lack of plasma jS-lipoprotein and consequently no circulating alpha tocopherol, responds to vitamin E treatment. In neonates requiring oxygen therapy vitamin E has been used for its antioxidant properties to prevent the development retrolental fibroplasia. It should be noted that high dose vitamin E supplements are associated with an increased risk in allcause mortality. 

It is known that 02 is potentially toxic as was evident in premature infants where it caused retrolental fibroplasia (2) or in artificial ventilation where it caused pulmonary lesions (3) because of the formation of ROS. 

Down syndrome Retrolental fibroplasia Cerebrovascular disorders Ischemia reperfusion injury... 

Oxygen toxicity in the eye can cause tunnel vision by an effect on the retina (7) and, in neonates, retrolental fibroplasia (8) (SED-12, 242). 

Premature infants and children with chronic cholestasis may develop spontaneous vitamin E deficiency. In premature infants, the deficiency manifests itself as increased red cell fragility and mild hemolytic anemia. It has been claimed, but not established, that these infants respond to administration of vitamin E. The anemia is not prevented by vitamin E, and only small improvements in red cell indices follow vitamin E treatment. A role has been claimed for vitamin E in prophylaxis of retrolental fibroplasia and bronchopulmonary dysplasia, two types of oxygen-induced tissue injury that occur in premature infants treated aggressively with oxygen. 

Retrolental fibroplasia (conversion of the retina into a fibrous mass in premature infants) Cerebrovascular disorders I sdiernia reperfusion injury... 

All. Ashton, N., Effect of oxygen on developing retinal vessels with particular reference to the problem of retrolental fibroplasia. Brit. J. Ophthalmol. 38, 397-432 (1954). A12. Attar, S., Esmond, W. G., and Cowley, R. A., H3rperbaric oxygenation in vascular collapse. J. Thoracic Cardiovascular Burg. 44, 759-770 (1962). 

C4. Campbell, K., Intensive oxygen therapy as a possible cause of retrolental fibroplasia, a clinical approach. Med. J. Australia 38, 48-60 (1951). 

Retrolental fibroplasia can occur when neonates are exposed to increased oxygen tensions these changes can progress to blindness. The incidence of this disorder has decreased with an improved appreciation of the issues and avoidance of excessive inspired oxygen concentrations. Adults do not seem to develop the disease. 

B. Oxygen therapy may increase the risk of retrolental fibroplasia in neonates. 

Owens and Owens (1949) in a pilot study found that in 11 infants receiving vitamin E supplements, no case of retrolental fibroplasia occurred whereas in 15 of the control group 5 developed the disease. When they extended their study they found 1 case out of 23 in whom tocopherol supplementation had been undertaken and 17 out of 78 with no such supplementation. This was supported by further studies from the same group (Owens and Owens, 1950) and by Kinsey (1950). Subsequent experience was not so favorable (Retrolental Fibroplasia, 1951 Kinsey and Chisholm, 1951 La Motte, et al., 1952 Coxon, 1952) although the technique and dosage used were not quite comparable. 

In recent years many attempts have been made to reproduce retrolental fibroplasia in animals. Several species of animals, notably the rat, mouse, and kitten have incompletely vascularized retinas at birth. Exposure of newborns of these species to high concentrations of oxygen (Ashton, 1957 Patz, 1957 Gyllensten and Hellstrom, 1956) produces obliteration of the retinal vessels. On return to normal oxygen tensions a vasoproliferative phase occurs with some destruction of the retinal cells. True retrolental fibroplasia only seldom occurs. One worker (Bhaduri, 1958) has shown that these effects can be prevented by addition of vitamin E to the diet in rats. Unfortunately, however, the study is not well designed and has so far been unconfirmed, though not refuted. 

Retrolental Fibroplasia 1951. Rept. 2nd Paediat. Res. Conf., N. York. 

There are few documented cases of harmful effects resulting from excessive intake of essential fatty acids in children. The syndrome related to vitamin E deficiency in premature infants described by Hassan et al (1966) was referred to earlier. Presumably, this could be exacerbated by increasing the level of polyunsaturated fat in the diet unless the levels of vitamin E were also increased at the same time. Johnson et al (1974) have provided some evidence that the occurrence of retrolental fibroplasia in premature infants is associated with vitamin E deficiency. 

One hundred percent oxygen at atmospheric pressure can cause pulmonary irritation and edema after 24 hours of exposure. The earliest symptoms are pleuritic substemal pain and dry cough, occurring after only 6 hours. Adult respiratory distress syndrome, which involves interstitial and intraalveolar fluid extravasation in the lung tissue, follows after 24 to 48 hours. Other known toxic effects include retrolental fibroplasia, which has occurred in premature infants exposed to high concentrations of oxygen at birth, retinal circulatory injury, and erythrocyte hemolysis in adults [5]. 

Allison and Orent Keiles found that the eyes of rats born of vitamin E deficient mothers showed retrolental fibroplasia such as is sometimes seen in premature human infants. The eyes were unusually small and the eyelids failed to open. There was an opaque white membrane behind the pupil in animals so affected, and in one animal the pupil was filled by a clot of blood. 

In principle, vitamin E deficiency can resulf from insufficient dietary intake, malabsorption or excessive consumption in case of oxidative stress in biomembranes. While the former is virtually nonexistent in Western society, the impaired ability to utilize dietary fats may create hypovitaminosis E in certain risk populations, e.g., patients with pancreatic dysfunction or defects in lipoprotein metabolism and particularly in premature infants. Deficiency disorders in the latter include bronchopulmonary dysplasia, retrolental fibroplasia (retinopathy), intraventricular hemorrhage, hemolytic anemia, and neuromuscular anomalies. 

Vitamin E has been used successfully in the therapy of progressive neuromuscular disease in children with liver or bile dysfunction and a number of diseases, which afflict prematurely bom infants, such as haemolytic anaemia, intraventricular haemorrhage and retrolental fibroplasias, which can produce blindness. 

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