Course: Visual Assessment of Children: The Orthoptist Role
Presented on Wednesday 9 February 2005
Multidisciplinary Functional Vision Assessment
Gillian Coyle, Senior Orthoptist
Functional vision
The ability to use sight in everyday situations
It allows:
- Access to information
- Social interaction
- Mobility
Functional Vision Assessment Team
- Community Paediatrician
- Orthoptist
- Specialist Teacher for Visually Impaired Children
- Optometrist
Aims
- To describe the vision available in daily activities
- To identify the visual difficulties
- To develop strategies to help overcome the difficulties
- To maximise the use of residual vision.
- To enable the child to reach their development and educational potential
How is vision measured?
Traditional
Reduced Visual Acuity 6/18
Resudec visual acuity 6/60
Limitations - optimum conditions
- Lighting
- Maximum contrast
- Important but incomplete assessment of vision
How is vision measured?
Other parameters
The Assessment
- CDC or school
- Assessment
developmental age
severity of visual impairment
associated difficulties
History
- Paediatric
- Ophthalmic
- Visual
recognition, orientation, crowding, depth perception, visual memory, perception of movement, visual fatigue
Dutton et al, Developmental Medicine and Child Neurology 1999, 41: 298-306
Observed Visual Behaviour
Detection Vision
Visual Acuity Tests
Visual Field Testing
Visual field defects
- peripheral looss - tunnel vision
- hemianopia
Contrast sensitivity test
- Normal/reduced contrast
- Normal/defective colour vision
- Cone adaptation test - night blindness
Eye movements
- Maintain fixation on an object
- Follow moving object
- Look from one object to another
- Use the eyes together
- Observation of speed
Testing eye movements
Recognition of people