Related Experiment Video

Updated: Jun 27, 2025

Development of a Gaze-Contingent Display Framework Designed for Perceptual and Oculomotor Research with Simulated Central Vision Loss
07:12

Development of a Gaze-Contingent Display Framework Designed for Perceptual and Oculomotor Research with Simulated Central Vision Loss

Published on: April 11, 2025

325

Yoked prisms and cerebral visual impairment: Enhancing the experience of ambient vision

Sahithya Bhaskaran1, Sneha Pandurangan1, Vijayalakshmi Perumalsamy1

  • 1Department of Paediatric Ophthalmology and Strabismus, Aravind Eye Hospital, Madurai, Tamil Nadu, India.

Indian Journal of Ophthalmology
|April 25, 2024
PubMed

Insights

Yoked prisms effectively address perceptual vision disorders in children with cerebral visual impairment. These prisms improve exploration, hand-eye coordination, and obstacle negotiation, aiding rehabilitation.

Area of Science:

  • Ophthalmology and Neuroscience
  • Pediatric Rehabilitation

Background:

  • Cerebral visual impairment (CVI) in children often results in perceptual visual impairment, affecting functional vision.
  • Yoked prisms are utilized in vision therapy and neurorehabilitation for conditions like autism, visual neglect, and hemianopia, particularly for perceptual visual problems.

Observation:

  • Case studies demonstrate the application of 4-PD base-down yoked prisms in children with CVI-related perceptual vision disorders.
  • Improvements were observed in environmental exploration, grasp, obstacle negotiation, and hand-eye coordination.

Findings:

  • Yoked prisms facilitated spontaneous exploration and improved grasp in a child with periventricular leukomalacia.
  • Prism use enhanced downstairs climbing and obstacle negotiation in a child with CVI, potentially addressing inferior field awareness or optic ataxia.
  • Improved hand-eye coordination was noted in a child with CVI using yoked prisms for closer object focus.

Implications:

  • Yoked prisms offer a simple yet effective intervention for perceptual visual problems in children with CVI.
  • This approach can positively impact functional vision, motor skills, and spatial awareness in pediatric neurorehabilitation.
Abstract

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