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Visual acuity and visually evoked responses in children with cerebral palsy: Gross Motor Function Classification
F Ghasia1, J Brunstom, L Tychsen
1Department of Ophthalmology and Visual Sciences, St Louis Children's Hospital at Washington University Medical Center, One Children's Place, St Louis, MO 63110, USA.
Insights
Quantitative visual acuity measurements are possible in most children with cerebral palsy (CP), even those with severe motor dysfunction. This study demonstrates that visual acuity testing in CP children is feasible, challenging misconceptions about their vision.
Area of Science:
- Ophthalmology
- Pediatric Neurology
- Rehabilitation Medicine
Background:
- Assessing visual acuity in children with cerebral palsy (CP) presents significant challenges.
- Motor dysfunction in CP can complicate traditional eye examination methods.
Purpose of the Study:
- To determine the probability of obtaining quantitative visual acuities (logMAR) in children with CP.
- To correlate the success rate of visual acuity measurement with the severity of motor dysfunction in CP.
Main Methods:
- Observational, cross-sectional study of 76 children with CP, aged 5.9 years on average.
- CP severity was classified using the Gross Motor Function Classification Scale (GMFCS) and physiological-anatomical subtypes.
- Visual acuity was assessed using optotypes and visually evoked potentials (VEPs), including spatial-sweep (SSVEP) and flash (FVEP).
Main Results:
- Quantitative logMAR visual acuities were obtained in 88% of children with CP using optotypes or SSVEPs.
- Success rates decreased with increasing GMFCS levels, but measurements were still possible in 56% of children with Level 5 CP.
- The mean logMAR acuity in the CP cohort was poorer than in age-matched controls, indicating a visual deficit.
Conclusions:
- Quantitative visual acuity measurement is achievable in most children with CP, including those with severe motor impairments.
- The ability to obtain visual acuity data challenges the misconception that severe motor dysfunction equates to immeasurably low vision.
- These findings support the routine assessment of visual acuity in children with CP to ensure accurate diagnosis and management.
Background/Aims:
Measurement of visual acuity can be difficult in children with cerebral palsy (CP). The purpose of this study was to determine the probability of obtaining quantitative (logMAR) visual acuities in CP children with different severities of motor dysfunction.
Methods:
An observational, cross-sectional design study was conducted in 76 children (mean age 5.9 years) who had CP severity graded using the Gross Motor Function Classification Scale (GMFCS). Visual testing was performed using optotypes, spatial-sweep (SSVEP) or flash (FVEP) visually evoked potentials.
Results:
LogMAR acuity was obtainable in 88% of CP children, using either optotypes or SSVEPs. The success rate decreased with increasing severity of GMFCS Levels 1-5; nevertheless, logMAR acuities were obtainable in more than one-half (56%) of children with the most severe disease: Level 5. Similar results were obtained for CP severity assessed using physiological-anatomical subtype (hemiplegic; diplegic; quadriplegic) rather than GMFCS. The mean logMAR acuity (0.37; 20/48) in the CP cohort as a whole was approximately 2 Snellen-equivalent lines worse than that recorded in age-matched, normal children (0.22; 20/33).
Conclusion:
Quantitative visual acuities can be obtained in the majority of CP children, including those with severe motor dysfunction. Difficulties in testing CP children lead often to the misconception that the children have immeasurably low vision.
