Related Experiment Videos
[Functional eye testing in the mentally retarded]
Insights
Simple clinical tests effectively assessed vision in severely mentally handicapped children. Most children received a confident diagnosis, identifying functional blindness and visual field defects early.
Area of Science:
- Ophthalmology
- Developmental Pediatrics
- Neuroscience
Context:
- Assessing visual function in severely mentally handicapped children presents unique challenges.
- Sheridan's simple clinical testing procedures offer a practical approach.
- Visuo-motor behavior studies in animals informed the methodology.
Purpose:
- To evaluate the efficacy of Sheridan's simple clinical testing procedures for assessing visual functions in severely mentally handicapped children.
- To determine the presence or absence of functional vision in a cohort of 30 children.
- To identify specific visual impairments such as functional blindness and visual field restrictions.
Summary:
- Vision was tested in 30 severely mentally handicapped children using Sheridan's methods.
- Functional vision was confidently assessed in 29 out of 30 children.
- Thirteen children were identified as functionally blind, and visual field defects were noted in 10 out of 17 assessed children.
Impact:
- Highlights the importance of early detection of visual defects in this population.
- Demonstrates the utility of adapted clinical tests for assessing vision in challenging pediatric cases.
- Provides data on the prevalence of visual impairments among severely mentally handicapped children.
Abstract:
Simple clinical testing procedures, devised by Sheridan, to test visual functions in young and/or handicapped children are discussed. Using these methods, combined with experience obtained in studying visuo-motor behaviour in cats, vision was tested in 30 severely mentally handicapped children. For 17 of these, it was unclear whether they possessed any usable visual functions. For 29 out of the 30 tested children it was possible to reach a reasonably confident conclusion regarding presence or absence of functional vision. Thirteen patients appeared to be functionally blind. In 17 children the size of the visual field could be determined; 7 showed normal, 10 restricted visual fields. In 6 children acuity could be measured. The importance of early detection of visual defects is discussed.