Robert H. Duckman

Ocular dominance and amblyopia

&NA; Ocular dominance, as measured in sighting tests, involves a temporary suppression of the input from the non‐dominant eye in order to avoid diplopia. Amblyopia ex anopsia may be viewed as a long term suppression of the input from one eye for the same reason. In the absence of anisometropia, paralysis of extra ocular muscles, or other factors which would tend to determine which eye would manifest suppression, the non‐dominant sighting eye should be more likely to develop amblyopia given the presence of strabismus. A sample of 258 amblyopes supports this prediction based on the population norms for sighting dominance.

Evaluation of intraocular pressure in a pediatric population.

The purpose of this study was to examine the intraocular pressure (IOP) in a pediatric population without general anesthesia, and compare it to the IOP in a normal adult population. Little information is available on the normal IOP in a pediatric population. IOP was measured in a sample of 212 eyes (111 patients) using the Keeler Pulsair Hand Held Non-Contact Tonometer to determine the range of IOP in this population. Patients ranged in age from 7 months to 5 years, 10 months. The mean IOP of each eye was based on three readings. These IOP values were grouped by the chronological age of the children. The results support the conclusion that infant/toddler patients have lower mean IOP than adults and that as age increases, IOP increases

Use of photoretinoscopy as a screening technique in the assessment of anisometropia and significant refractive error in infants/toddlers/children and special populations.

ABSTRACT The presence of significant refractive error and/or anisometropia can produce an irreversible decrease in visual function if not detected and treated at an early age. The general consensus is that the earlier a problem is detected, the easier the process of remediation. The authors have examined photoretinoscopy as a means of screening infant/toddlers and/ or nonverbal persons for refractive anomalies. Fifty adults and fifty infants/toddlers/children were photographed and the estimated refractive error from review of the pictures was compared to the refractive error obtained from retinoscopy. The results indicate that photoretinoscopy is an effective screening procedure for the detection of significant refractive error and is extremely sensitive to anisometropia.

Accommodative Adaptation in Children

Although accommodative adaptation has been studied extensively in young adult populations, there has been little consideration of this function in children. Accordingly, we examined accommodative adaptation by comparing pre- and post-task measurements of dark accommodation (DA) in children and young adults. DA was assessed objectively before and immediately after a 5-min near-vision task (viewing distance=20 cm) using an open-field, infrared optometer (Canon Autoref R-1). The study was performed on 15 visually normal children (mean age=10.1 years) and 10 visually normal young adults (mean age=25.2 years). No significant difference was observed between the mean values of pre-task DA for the two age groups (children=1.01 D, adults=0.88 D). Both groups showed equivalent degrees of accommodative adaptation (approximately 1.0 D), and the rate of regression of post-task DA to the pre-task level was similar for each group. We found a significant positive correlation between the magnitude of adaptation and pre-task DA in children, which was not found in the young adult population. The results indicate that pre-task DA and accommodative adaptation (both in terms of magnitude and rate of decay) are similar in adults and children. This would not support the proposal that the development of nearwork-induced myopia in children is related to short-term variations in accommodative adaptation when compared with young adults.

Use of forced preferential looking for measurement of visual acuity in a population of neurologically impaired children.

ABSTRACT The forced preferential looking (FPL) technique has been used clinically, to assess visual acuity in infants for the past decade. It is generally accepted that the effectiveness of the procedure extends to the upper limit of 10 months of age. The authors discuss clinical observations on the viability of FPL as an effective technique in the measurement of visual acuity in an older population of neurologically impaired children.

Management of Binocular Anomalies: Efficacy of Vision Therapy, Exotropia

This paper presents a survey of the literature on management of the various forms of exotropia. Criteria for success of treatment are examined. A table summarizing the results of 11 studies is given.

Vision status among foster children in NYC: a research note.

Abstract A summary of the results of research on the vision status of foster children. Results indicate that the vision screenings being provided at mandated annual physical examinations are not sufficiently identifying childrens vision dysfunctions.