The child with poor vision not only faces many personal hardships through his early developing years but also presents numerous problems and challenges to the responsible adults in his life. All who are in contact with the visually impaired child are affected, with those who are the closest sharing the greatest concern and bearing the heaviest burden. It is the accepted responsibility of the parents and siblings, the pediatrician, the ophthalmologist, and educators to promote the physical and psychologic well-being of all children while enabling them to develop the skills necessary to live safely and happily in our society.
Although this issue was originally entitled "The Bund Child," early discussion recognized that total blindness in the pediatrie population is a much less common occurrence now than in previous decades. The remote residential institutions that served as both home and school for many thousands of blind children today have many fewer occupants. For children who are visually impaired to a moderate or severe degree, every effort is made to enable them to learn and perform in classroom settings that provide the "least restrictive environment" and the opportunity to function in as nearly normal a life setting as possible.
Other than congenital and developmental cataracts, the major causes of childhood visual disability today are those related to the abnormal structure and development of the eye or its neural connections and abnormal function of the sensitive neuroocular tissues. Not only are cataracts the greatest single threat to visual development in children today, but their recognition is particularly important, since the impaired vision is usually recoverable with the benefit of early identification and the institution of appropriate treatment on a timely basis. A major discussion of cataracts in childhood will be found elsewhere in this issue.
Although severe visual impairment in a segment of our pediatrie population remains a serious medical, educational, and socioeconomic problem, several major advances in medical research and technology have contributed to a significant reduction in childhood blindness. Four factors that have had a major effect on the prevention of visual disability in children will be discussed individually:
1. The identification and containment of the causes of retrolental fibroplasia.
2. The effective control of rubella.
3. Early identification and referral of threatening eye conditions.
4. Significant advances in pediatrie ophthalmic surgery.
Retrolental fibroplasia (RLF), the retinopathy found to be related to the administration of high concentrations of oxygen to susceptible lowweight prematures, was characterized by bilateral abnormal retinal vascularización, often leading to an advancing course of retinal scarring, retinal detachment, degeneration of the eyes, and blindness.
Compelling figures gathered in the National Society for the Prevention of Blindness periodic survey noted that during the peak years of RLF incidence, this condition accounted for almost onehalf of the blindness and severe visual disability in the children. Of the children affected by RLF, at least 42 percent had no useful vision and fully 23 percent were totally blind. The majority of these tragically affected children have now passed through our school systems.
Recognition of the causes of RLF and institution of appropriate measures to monitor and control oxygen therapy in the premature newborn have provided a dramatic decrease in the incidence of this often preventable condition. With the present sophisticated level of neonatal care and the high incidence of salvage of the immature and premature, however, RLF will not be eradicated but remain at an irreducible lowest possible level of approximately 2/100,000, considerably decreased from the peak of 12/100,000 in the 1950-60 decade. This now constitutes approximately 8 to 10 percent of the childhood blindness in this country.
The congenital rubella syndrome, in addition to causing major systemic defects of the cardiovascular and central nervous systems,* included a very high incidence of cataracts with severe ocular morbidity, second only to RLF. Cataracts, microphthalmia, glaucoma, iris hypoplasia, and chronic uveal inflammation all resulted from the devastating effect of rubella virus in the developing fetal eye.
Not only did this extensive rubella panophthalmopathy cause severe deficits in visual function, but the chronic inflammation in these congenitally infected tissues further complicated and compromised the usually effective techniques for cataract removal that were being perfected by experienced ophthalmic surgeons. Although sporadic cases of rubella with ocular defects are still encountered, the highly effective immunization programs have nearly eradicated this viral threat as an important cause of childhood blindness in this country.
Early identification and referral of visionthreatening conditions are essential to the development of good vision. Research in the past decade has documented that early retinal stimulus, with accurate form transmission, is needed if the child is to have good vision; conversely, the early deprivation of form vision, as with cataracts, may result in permanent and irrecoverable visual loss. In order to provide effective treatment for these conditions, which threaten the development of vision in the young, early identification and referral are imperative. The opportunity and responsibility fall to the pediatrician and other physicians who furnish the children's primary health care.
Advances in pediatrie ophthalmic surgery in recent years have contributed immeasurably to the treatment of cataracts and glaucoma in infants and children. Among the important factors are the general availability and use of operating microscopes, the development of fine microsurgical instruments and sutures, the evolution of minute mechanical suction /cutting instruments to operate with precision within the eye of even small infants, and the numerous advances in techniques developed by a rapidly increasing number of specialists trained in pediatrie ophthalmic surgery.
Because of these many factors there has been a remarkable improvement in the results of congenital cataract and congenital glaucoma surgery in recent years and a concomitant decrease in the incidence of those operative and postoperative complications that previously contributed to much of the related ocular morbidity.
Future advances in the prevention and treatment of visually disabling conditions will require great assistance from our confreres in the basic and clinical research fields.
To find answers for such varied problems as albinism, nystagmus, optic atrophy., and the many forms of retinal abiotrophies and degenerations will necessitate many major breakthroughs in our present state of knowledge. We will rely more and more on the geneticist, immunologist, neurophysiologist, and enzyme biochemist to further reduce the RLF threat and eliminate toxoplasmosis and the herpesvirus.
The gains have been great, but much remains to be accomplished until the last white cane is set aside and Seeing Eye dog retired.