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Comparative evaluation of Teller and Cardiff acuity tests in normals and unilateral amblyopes in under-two-year-olds
Pradeep Sharma1, Debasis Bairagi, Murli M Sachdeva
1Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, Ansari Nagar, New Delhi-110 029, India. anudeep87@vsnl.com
Insights
Cardiff Acuity Cards (CAC) are child-friendly for vision testing, but Teller Acuity Cards (TAC) are more reliable for detecting amblyopiogenic conditions in young children.
Area of Science:
- Ophthalmology
- Pediatric Optometry
Background:
- Assessing visual acuity in infants and toddlers is crucial for early detection of visual impairments.
- Teller Acuity Cards (TAC) and Cardiff Acuity Cards (CAC) are commonly used methods for pediatric vision screening.
Purpose of the Study:
- To compare the efficacy and reliability of TAC and CAC in assessing visual acuity in children under two years of age.
Main Methods:
- Evaluated TAC and CAC in 90 normal children across three age groups (0-6, 6-12, 12-24 months).
- Included children with unilateral amblyopiogenic conditions, refractive errors, esotropia, and cataracts.
- Binocular and monocular testing was performed by trained optometrists, with test duration recorded.
Main Results:
- Both TAC and CAC demonstrated ability to assess visual acuity, with CAC being quicker but having a higher coefficient of variance.
- Both tests correctly identified reduced visual acuity in strabismus and cataract cases.
- CAC showed limitations in detecting some visually significant refractive errors compared to TAC.
Conclusions:
- Cardiff Acuity Cards (CAC) are a practical, child-friendly option for clinical vision assessment.
- Teller Acuity Cards (TAC) provide more dependable results for identifying amblyopiogenic conditions, despite using gratings.
Purpose:
To compare and evaluate Teller Acuity Cards (TAC) and Cardiff Acuity Cards (CAC) to assess vision in children below the age of two.
Methods:
The study evaluated TAC and CAC to assess visual acuity in 90 normal children divided into three age groups, 0-6 months (group I), 6-12 months (group II) and 12-24 months (group III). 30 cases of unilateral amblyopiogenic conditions, 10 cases each of unilateral refractive error, unilateral esotropia, and unilateral cataract, were also examined. Trained optometrists carried out binocular testing followed by monocular testing, and recorded the test time in each case.
Results:
The mean visual acuity (in Snellen units) and standard deviation (in octaves) in the three age groups of normal children, I, II, III respectively were 6/44 +/- 0.54, 6/21 +/- 0.37 and 6/21 +/- 0.41 (binocularly by TAC) and 6/46 +/- 0.80, 6/21 +/- 0.59 and 6/14.5 +/- 0.84 (binocularly by CAC). Although the time taken for testing with CAC was less, its coefficient of variance was greater for all age groups as compared to TAC. Diminution of visual acuity could be assessed correctly by both the tests in cases of strabismus and cataract, but not in some cases of refractive error.
Conclusion:
CAC is a useful and child-friendly test. It can be used clinically but may miss some cases of visually significant refractive errors. TAC is a more dependable test to assess amblyopiogenic conditions despite the use of gratings.
