An Experimental Stuiy on the Effect of Oxygen on Retinal Dysplasia in the Rat

ABSTRACT

Retinal dysplasia refers to a generally nonspecific lesion resulting from interference with the normal histogenesis of the developing retina. An earlier review of the pathogenesis of retinal dysplasia indicated that this lesion might re.sult from a wide variety of etiologic causes, including congenital retinal fold or chromosOJn;ai1 abnormality asaociated with generalized anomaly such as 13-15 trisomy syndrome etc. Recently, Ulany experimental retinal dysplasias have been induced by viral infection, irradiation or intrauterine mechanical damage. The single pathogenetic basis of retinal dysplasia appears to be associated with separation of t-the retina, during a critical stage of differentiation, from its underlying pigment epithelium which play an important role to transport nutrition and oxygen from choroid to outer retinal layers. In this experiment, authors aspirated lens material as much as possible at 5 days after birth, and administrated oxygen for 5 days in group I, 10 days in group 2 and 15 days in group 3 except for control group. Retinal dysplasias were developed in all instances, but noted lesser incidence of dysplastic formation in group 3 as compared with control or group 1 in which round and oval shaped rosettes, irregular infoldings, indifferentiated cell masses and separation of the developing retina from its normal relationship to the pigment epithelium were observed microscopically. The shape and origin of rosette in retinal dysplasia appeared to similar that of retinoblastoma in morphology.