The baby with poor visual contact.

Normally, full term babies show evidence of visual fixation at birth or shortly afterwards. 1 Visual following responses have even been observed in prematurely born babies. 2 The absence of visual responsiveness in a baby of more than 8 weeks old has to be taken seriously and warrants careful investigation. Parents are anxious to understand the reason why the baby seems not to see, and want to know the visual prognosis. Visual inattentiveness in a baby can be due to very heterogeneous causes. Obvious causes of visual impairment are bilateral cataracts, persistent hyperplastic primary vitreous, retrolental fibroplasia, chorioretinal colobomata, etc. However, in many babies no underlying cause can be found on routine ophthalmological examination. There are also many pitfalls. For example, the infantile optic disc can be paler than that of an older child and the macula and fundus may be more mottled, which could lead to erroneous diagnoses of optic atrophy and retinal pathology. An incorrect diagnosis of visual impairment in an infant can be devastating to the family. Clinical signs can be typical, but additional technical examinations are necessary in most patients. Visual development The normal function of the visual system in large part parallels the anatomical development. Prenatal development of the eye and brain occurs relatively early in comparison with other systems. By 6 weeks of gestation, the ocular structures and diVerentiation of the brain are fairly well developed. The visual system is relatively mature at birth. After birth diVerential growth of the eye occurs. The anterior structures are, in general, more completely developed than the posterior segment of the eye. In addition to the postnatal growth of the eye, the central visual system is also maturing. The timing of premature birth is significant for the immature visual system. 3 Excluding those infants who have suVered complications of preterm birth, the development of visual acuity in the infant born before term appears to progress at a rate similar to his or her term counterpart—as though birth had occurred at term. 4 5 Contrasting with these reports, superiority of acuity in pre-term subjects has been documented in several behavioural and electrophysiological studies indicating the possible beneficial eVects of the environment. 6 7 Studies so far are relatively few, and more research is required to determine whether premature birth and its accompaniments either accelerate or retard any aspect of visual development. In prematurely born babies who suVered complications visual …