Creig S. Hoyt

Monocular Axial Myopia Associated with Neonatal Eyelid Closure in Human Infants

We studied eight infants who developed unilateral axial myopia associated with neonatal eyelid closure. Clinical findings and ultrasonographic biometric measurements suggested that axial elongation of the eye may occur as a result of neonatal eyelid closure, a finding similar to that for experimental myopia produced in neonatal animals after eyelid fusion. Early treatment of eyelid occlusion in the neonate may prevent axial myopia and subsequent anisometropic amblyopia.

Optic nerve hypoplasia

Optic nerve hypoplasia is an easily overlooked, nonprogressive developmental anomaly which results in a wide range of visual deficits. It is frequently associated with clinically significant central nervous system and endocrine abnormalities. Maternal substance abuse is increasingly recognized in many cases. A supranormal regression of optic nerve axons in utero, rather than a primary failure of differentiation, is proposed as the pathogenesis.

Long-Term Visual Results in Bilateral Congenital Cataracts

In 24 infants who underwent surgery for bilateral congenital cataracts, 29 eyes (60%) achieved visual acuities of 6/18 (20/60) or better and 13 (27%) had visual acuities of 6/60 (20/200) or worse. The best results occurred in patients who underwent surgery before they were 8 weeks old. Only one patient of the seven operated on after the age of 8 weeks achieved a visual acuity of better than 6/60 (20/200). These favorable visual outcomes were the result of early surgery, short intervals between operations on fellow eyes (48 hours or less), total bilateral occlusion between operations, careful postoperative monitoring with retinoscopy and visual-evoked potentials, and early correction of aphakia.

Autosomal dominant optic atrophy. A spectrum of disability.

Autosomal dominant optic atrophy is an abiotrophy with an insidious onset in the first decade of life. The clinical features of 31 individuals in six pedigrees are detailed in this study. These data suggest that here is considerable intrafamilial and interfamilial expression of dysfunction. Moreover, asymmetry of the visual loss in not unusual. An unexpected result of this study is the previously unreported frequent association of a neural hearing loss with this disorder.

Chronic cortical visual impairment in children: aetiology, prognosis, and associated neurological deficits

BACKGROUND/AIMS To evaluate prevalence, aetiology, prognosis, and associated neurological and ophthalmological problems in children with cortical visual impairment (CVI). METHODS The records of 7200 outpatients seen in the paediatric ophthalmology practice over the past 15 years were reviewed in order to compile data concerning CVI. In addition, the authors devised and applied a system for grading visual recovery in order to assess prognosis. RESULTS CVI occurred in 2.4% of all patients examined. The four most common causes of CVI were perinatal hypoxia (22%), cerebral vascular accident (14%), meningitis (12%), and acquired hypoxia (10%). Most children with CVI had associated neurological abnormalities. The most common were seizures (53%), cerebral palsy (26%) hemiparesis (12%), and hypotonia (5%). Associated ophthalmological problems were esotropia (19%), exotropia (18%), optic nerve atrophy (16%), ocular motor apraxia (15%), nystagmus (11%), and retinal disease (3%). On average, CVI patients improved by two levels as measured by the authors’ scale. CONCLUSION The majority of children with CVI showed at least some recovery. In this group of children, CVI is often accompanied by additional ophthalmological problems and is nearly always associated with other, serious neurological abnormalities.

Behavioural characteristics of children with permanent cortical visual impairment.

The common behavioral features of 50 children with permanent cortical visual impairment (CVI) are described. CVI is frequently associated with specific behavioural characteristics. The majority of these children have residual vision, but they all have variable and inconsistent visual performance, including visual acuity. They see better in familiar environments and when they understand what to look for and where to look for it. They often use touch to identify objects. Their ability to identify colours is much stronger than their perception of form. Many turn their heads to the side when they are reaching. Nystagmus and visual self‐stimulation are exceptionally rare. They appear to have great difficulty with the cognitive evaluation of visual perception in spatial terms. Head elevation is worst in those with least vision, and without head elevation the possibility of visual stimulation is further restricted.

Congenital nystagmus: A clinical perspective in infancy

In a series of 152 patients with congenital nystagmus, 119 had sensory nystagmus while 13 had pure motor nystagmus. The most common diagnoses in the sensory group were optic nerve hypoplasia. Lebers amaurosis, and oculocutaneous or ocular albinism. Eight of the patients in the motor group had a similarly afflicted parent. Diagnostic features in infants and preverbal children were reviewed. This study supports the continued clinical classification of congenital nystagmus into sensory and motor subtypes.

Cryotherapy for Retinopathy of Prematurity

With the rapid progress in neonatology saving more lives of very immature infants, the occurrence of retinopathy of prematurity or retrolental fibroplasia has increased although most cases spontaneously resolve, severe visual damage and blindness still occur. The progressive case of retinopathy is a dilemma for ophthalmologists consulting in the intensive care nursery. The Japanese have been pursuing modalities of treatment of the acute case, but there are few reported cases in the United States and Canada. Four cases of retinopathy of prematurity treated by cryotherapy are presented with follow-up. This is done in an effort to stimulate further reporting and consideration of treatment of such cases.

Delayed visual maturation in infancy.

We describe the clinical and electrodiagnostic features of 8 infants who showed no visual responsiveness and were thought to be severely visually impaired on initial examination. Subsequently all children developed normal visual capabilities and the previously abnormal visually evoked potentials became normal. The clinical and electrodiagnostic features of these infants suggest that they suffered from a widespread cortical maturation delay.

Monocular Nystagmus in Infancy and Early Childhood

Of 11 young children (six girls and five boys, ranging in age from 4 to 14 months) with monocular nystagmus, six were found to have chiasmal tumors whereas only four had spasmus nutans. Differentiating features between these two groups included decreased vision and optic nerve anomalies (including four cases of optic nerve hypoplasia) in the tumor group. However, we found that no consistent clinical finding absolutely separates these groups. We therefore recommend that all infants and children with monocular nystagmus or the other features of spasmus nutans should undergo computed tomographic scanning.